1941 Buick Limited Limousine

[Matt Harwood]

Well, the air bubble was gone this morning, so maybe something is happening after all. I can't see any notable fluid movement in the tubing yet, but I suppose that's a good sign.

 

 

I also reversed the hoses on the block this morning so it's flowing in the same direction as it does under normal operation. Going in reverse (in at the top and out at the bottom) was probably trapping a lot of air in the head even under pressure, so hopefully I'm hitting all the water jackets in the block AND head at at this point. The Evapo-Rust still looks pretty clean so I'll just give it time to work.

[valk]

Since you didn't go for my temp gun suggestion which would tell you definitively whether your running hot, look at the plugs. Should be easy to tell if you're way too lean on the rear 4 cylinders.  I check my plugs after every long run and make small adjustments to dial in the right setting. 

[Matt Harwood]

2 minutes ago, valk said:

Since you didn't go for my temp gun suggestion which would tell you definitively whether your running hot, look at the plugs. Should be easy to tell if you're way too lean on the rear 4 cylinders.  I check my plugs after every long run and make small adjustments to dial in the right setting. 

 

It wasn't that I didn't go for it, it's that the car is currently inoperable without a water pump or radiator and since it's the middle of winter, I couldn't really take it out for a long, hot drive anyway. I do have a temperature gun, but it wasn't until the car was totally disassembled that I even noticed the burned ceramic coating so I didn't even know there was an issue. All indications were that the car was perfectly healthy and running great--I had no reason to go looking for a problem because none were evident in the car's operation.

Of course the first thing I am going to do once it is reassembled is take it out and get it hot and then I'll check all the temperature points, both in the cooling system and the exhaust system. In the meantime, it's my plan to pull the plugs and have a look.

 

Nothing adds up right now. A great-running car that maintained 165 degrees under almost all circumstances and never went above 180 no matter what, is now showing anecdotal signs of serious overheating in several cylinders. A car that started instantly, idled well, didn't burn its oil, and didn't blow smoke seems to have a fuel mixture so out-of-whack that EGTs are above 1900 degrees. I just can't reconcile those things.

[valk]

Of course, my apologies. I'm a bit skeptical it's the fuel mixture because it would have run like crap with the mixture so wrong.  You know more than I but I would put it back together and take the temp checks you mentioned to confirm there's a problem. Might be other reasons the header paint failed. 

[Lawrence Helfand]

13 hours ago, Matt Harwood said:

Went up to the hardware store and picked up some fittings to connect a second line to that blocked drain plug in the block and let the Evapo-Rust work on it from both sides. Unfortunately--and like usual--the car had other ideas. Turns out that the little plug in the block is indeed 1/4 NPT (pipe thread) but it's not tapered like a pipe thread. So it's the same but different. Why? Why do they do it that way? Every little thing unique. So I screwed in a 1/4 NPT fitting and felt it snug up, which I thought was good, but turns out it actually started stripping threads. I left it in there since it seems to be holding pressure, but I'll have to figure something out later once I need to seal it up. I'll probably have to drill and tap it for a 3/8 NPT plug. Won't that be delightful down there in the engine bay?

 

Installed a fitting and some tubing to feed Evapo-Rust to the 

drain hole in the block. Note the air bubble...

 

It certainly appears that the drain hole is well and truly blocked. You can see the air bubble in the tubing above, demonstrating that there's zero movement of the liquid into the block. I loosened the fitting slightly to bleed off most of the air, but that's as much as I could get out without having liquid spraying all over the place. I do seem to recall that when I first bought the car, I had a local mechanic back-flush the block for me and he told that the drain plug was blocked; in his opinion it was a casting flaw and maybe it was never fully drilled out. I guess we'll find out. Maybe a pinhole will open up and the fluid will start to flow into the block. Or maybe I'll need to drill it out for a 3/8 plug anyway.

 

I also spoke with the folks at Sanderson Headers, who did the ceramic coating on my header. While they're perfectly willing to re-coat the headers--which I appreciate--they are also of the opinion that the air/fuel mixture is way out of whack and exhaust gas temperatures (EGTs) are so high that it's burning off a coating rated to 1900 degrees (they did note that the bolt adjacent to cylinder #8 is discolored, which would suggest a lot of heat). I don't rightly know how an engine with 7.5:1 compression and running under 3000 RPM could possibly generate that much heat, but OK, I'll look into it. I'll pull the plugs first and see what's going on, particularly in the rear cylinders. They also suggested using a 4-gas analyzer to tune it, and fortunately I have a friend who has one, so I'll do some more tuning once it's reassembled. Bigger jets in the carbs? Smaller? Just adjust the idle screws? 

 

I just can't understand how a car could run this well, this cool, and for this long if it had cylinders burning so hot that it destroyed a high-temperature ceramic coating. 

 

And, of course, the hits kept coming. The radiator shop called and told me that every time they fixed a seam on my radiator, another one would blow. The radiator is shot. Again, how the hell did this car run so cool and so effortlessly for so long with a junk radiator, super lean fuel mixture, bum water pump, and clogged water jackets? How?!?

 

Anyway, I told them to re-core the radiator. They have a modern 5-row core with straight fins that's slightly cheaper than a duplicate of the original core (it'll only be $1100), while an original-style core would probably be closer to what I paid for the Lincoln's radiator ($1800). Even though it should be better than before, I have a genuine concern that more changes will upset whatever perfect balance I had going on and it'll never run cool again. That's how things usually work for me--simple for everyone else, everyone else gets results, but when I try everything goes sideways. A new radiator, new water pump, and clean water jackets should mean it will run cool.

 

Anyone want to bet $10 that it runs worse than ever once I put it back together? I have zero faith in my abilities anymore. Bah.

Hi Matt, Sorry to hear of more issues with the limited. I am having some myself and its upsetting indeed. I had my radiator recored for about 400$ a couple of years ago and am stunned at the amount you mentioned. I used a great shop on Long Island NY    http://caparadiator.com/  Worth sending it to them. Hopefully still as cheap. 

[kgreen]

Matt, I wonder if your rearward cylinders might be running a little lean compared to the forward cylinders?  If this was the case then symptoms could be hard to detect and if too lean will cause higher operating temps but only in the cylinders with low fuel to air ratios.  Does the entire length of your exhaust manifold have baked coating? Possible conditions causing a cylinder to run lean could include a vacuum leak, but also some intake manifold condition causing different air/fuel ratios to the individual cylinders.  Just hypothesizing from 328 (or whatever) miles away.

 

Also, air fuel ratios at idle are not typical as are the conditions are when the engine is running at higher rpm's.  Air fuel ratios at idle are governed by the metering rather than the orifice velocities through the carb.  That said, measured EGT's at idle are not as accurate as they are at speed.  The burnt ceramic coating, to me, is sufficient indication of high EGT's out of your rear cylinders.

Edited February 19, 2020 by kgreen (see edit history)

[Walt G]

Matt, I know there are a lot of us reading all the issues you are experiencing and going through and the effort you are putting in to get your 90 series "right" again , thinking "we wish we could be there to help" in some way. Many of us own the same era cars with the same engine! Your experiences as frustrating as they may be are a REAL LEARNING experience for the rest of us! I think I can say for all of us - thank you for sharing what you are working on as well as how you are trying to solve the problems of an 80 year old motor. AND YES these grande old cars still give us pleasure.

Walt

[Matt Harwood]

I'm still not convinced anything is wrong. This was supposed to be simple preventive maintenance, nothing was broken. Yes, the water pump was a little noisy and one of the seams on the radiator leaked a little, but it has been that way for years. The car ran like a freight train and maintained 165 degrees (on a very accurate gauge) almost all the time. As a result, I'm not really attacking this situation as "solving a problem," but rather using it as an opportunity to prevent future ones.

 

I took this photo yesterday showing the header collector, which is also flaking. It's certainly possible the engine is running so lean that ALL the cylinders are extremely hot, but I'm not sure a car with 7.5:1 compression running below 3000 RPM could generate so much heat that the entire header would be heated to to the point of failure. I mean, the sucker would glow red at night if it were really running THAT hot. Other nearby equipment and paint would be getting cooked. Welds would be failing. My T-304 stainless exhaust system would be blue. And it would not start instantly, idle almost silently, and hammer along at 65 MPH for hours on end at 165 degrees with a sub-standard radiator and clogged cooling passages. Plus there's a big carburetor RIGHT THERE feeding the rear cylinders. The very same carburetor that fed all 8 cylinders perfectly for years before I moved it to the rear position. No, one symptom does not suggest a disease. I really do believe the coating is simply defective.

 

Coating is flaking all the way down on the collector. Not sure
this particular engine can generate that much heat.

 

It's certainly worth investigating the carburetors and I'm going to use my friend's 5-gas analyzer, but if anything the thing seems to be rich, not lean given my hard-start-when-cold issue. I believe everything is pretty close to right, because it runs beautifully. Nothing could run this well if things were THAT wrong. No way.

 

My plan is to simply work the plan. Install the new water pump, install the new radiator, clean out the water jackets as best as I can (my little electric Evapo-Rust pump finally gave up the ghost yesterday after a month of near-constant operation), and put it all back together. Use the carburetor tweaks recommended earlier in this thread to get the chokes dialed-in, use my friend's gas analyzer to tune it properly, and then when it's warm enough outside to give it a real-world test, go out and hammer it. Then I'll evaluate temperatures on the exhaust and in the cooling system.

 

And then we'll know for sure.

[carbking]

Matt - a handheld infrared pyrometer is not overly expensive.

 

Jon.

[Matt Harwood]

17 minutes ago, carbking said:

Matt - a handheld infrared pyrometer is not overly expensive.

 

Jon.

 

I have one. As soon as the car is running again, that's my first test. I didn't know about any of this other stuff until I disassembled the car.

[38Buick 80C]

For what it's worth I have had an issue with flaking powder coat on my factory manifolds on my 320 due to heat. This is on my 80C where everything was baked and cleaned and re-cored, etc. 

[EmTee]

On 2/19/2020 at 7:47 AM, kgreen said:

Also, air fuel ratios at idle are not typical as are the conditions are when the engine is running at higher rpm's.

 

I agree that idle and cruise are two different situations.  It seems to me that it's possible to have good air/fuel at idle and become lean at high RPM.  Cam timing (i.e., intake/exhaust overlap) increases scavenging at high RPM.  Add to that the fact that your fancy headers must be much less restrictive than the original 'log' manifold.  You may need to increase main jet size.  As others have said reading the spark plug condition and EGT should tell you what's going on.

[John_Mereness]

Powder coat on exhaust manifolds is really not the way to go for durability - I do not believe you have a problem.

[Matt Harwood]

On 2/22/2020 at 11:57 AM, John_Mereness said:

Powder coat on exhaust manifolds is really not the way to go for durability - I do not believe you have a problem.

 

It's not actually powder, it's a ceramic coating. Not precisely sure what the difference is, but it's specifically designed for this application. It's the way the Sanderson headers come from their factory and they offer a lifetime guarantee. Since mine were not technically made by Sanderson (I cut up a set of their small block Chevy headers and modified them extensively) they were willing to coat them using the same process and they're standing behind it. They'll re-coat them if I want them to. Their advice that something is amiss is what led me down this rabbit hole. I'm currently of the opinion that these are simply symptoms in search of a disease, and once it's back together I'll be able to assess.

 

And with that, I am closer to putting it back together. I picked up my beautiful new radiator and it's ready to install. Ellet Radiator does nice work and used the original tanks and side panels with a new core. I've expressed my concerns about whether a new core will work as well as the old one, but no way to know until we drive it in the heat of the summer. It certainly looks beautiful and it's enormous--easily four inches thick. Original fittings and tanks make it look right and hopefully it will have a flow rate about equivalent to the original so that the water pump moves the coolant properly. I'll paint the water pump tonight and put it all back together this weekend--we have a seminar here on Saturday so it'll probably be Sunday before I get to it.

 

 

New radiator certainly is beautiful.

 

 

Reusing the original tanks makes it look 100% original. Let's hope it cools as well as the old one!

 

In the meantime, I'll keep running the Evapo-Rust through the block. I repaired my little circulation pump, which gave up the ghost last week. I figured the impeller shaft had sheared since no fluid was moving. I took it apart and found that the shaft was intact and spinning, but the impeller was done. It's a little rubber impeller cast around a brass collar that locks it to the shaft. The rubber had simply detached from the brass collar and it was spinning helplessly. Also one of the vanes had broken off--you can see it in the photo below. Fortunately, replacement impellers are cheap and common so I ordered three spares for $20 and popped a new one in there. Good as new! I have to admit, I'm really impressed with this cheap Chinese pump. I expected it to give up the ghost weeks ago after continuous duty under load, but it hasn't missed a beat other than that cooked impeller which is apparently a typical issue. Not bad for $70.

 

You can see where the original impeller lost a vane and
its brass collar. New impeller works just fine!

 

 

Edited February 26, 2020 by Matt Harwood (see edit history)

[EmTee]

Ha -- that looks like an outboard motor water pump impeller...

 

[Matt Harwood]

I was hoping to have the cooling system all buttoned up this weekend, but I'm not sure I'll make it. I have all my parts painted and the others back from the powdercoater, the radiator is done, and the Evapo-Rust seems to have done its thing--the metal visible through the water pump openings is clean, although the block drain never cleared itself. I still managed to drain out all but about a gallon of Evapo-Rust, so I'll do a fresh water flush while I'm testing it, then drain and fill with coolant when I'm sure it's not leaking.

 

Parts ready to install. The fan should technically be satin black
instead of gloss black, but since I was doing a batch of gloss
black parts for the '35 Lincoln, I had them do the fan as well.
The pulley is satin silver, which approximates the original
cad plating. The Dante Red parts are painted using engine
enamel from Bob's.

 

The engine was rebuilt shortly before I bought the car and it appears that it was painted after assembly, including the water pump, so the block behind the water pump was bare and the rest of the front of the engine was pretty shabby. I cleaned it up, degreased it, and painted it Dante Red as well. The new paint matches the old pretty well and with the pump in place, nobody will notice. I found a number stamped into the block behind the water pump that I don't remember seeing before and I'm not sure what it means--it doesn't match the engine number stamped on the pan rail. A part number? Any ideas?

 

  
Front of the engine was pretty scruffy. No idea what the number stamped on the pad

means. I hit everything on the front of the engine with a wire brush and some solvent to
clean it in preparation for paint. Note the expanding freeze plug I used in the water pump
hole in the block, just to keep the remaining Evapo-Rust from trickling out and ruining
the wet paint. 

 

    
Finished. I used a little paint brush, which is easier to manage when there's a

lot of other stuff nearby. It gives a crisper result. While I was in there, I also
sprayed the frame and splash pan with some satin black. Not ideal, but
better than the bare metal and scale that was there before.

 

Now before I rush in and start reinstalling parts, I figured this would be the ideal time to fix the factory temperature gauge. Like most of them, the bulb broke off in the block and is stuck there, so the gauge is not working. Since I have the cooling system empty and apart, I figured I'll pull the broken bulb and install an NOS gauge I happened to have on the shelf. Unfortunately, while testing that NOS gauge I discovered that it, too, is inop--after all these years of being shuffled around, it probably suffered a small break in the tubing somewhere and the ether inside leaked out. Meh. I can find another and I guess I'll press on with the job and worry about it later.

 

NOS gauge is not working. That's OK, since the face is discolored
anyway. I'll try to find another or have John Wolf fix this one for me.
In the meantime, I'll put everything else together and get the car running.

 

I have new upper and lower hoses, correct hose clamps, a new 160-degree thermostat, and a fresh belt. I'll make fresh gaskets. I'm also glad I pulled that spring out of the old lower hose because the new one didn't come with a spring. One of the hassles with the installation is that little chunk of hose between the thermostat housing and bypass and the water pump--it's about two inches long and clamped on both ends. It's a bad design because the hose rots and you can't replace it without removing the thermostat bypass. I have some black silicone hose that I'm going to use along with a set of those heat-shrink hose clamps--it should look clean and last forever without the risk of leaking in the future.

 

Little chunk of hose between bypass housing and water pump
(arrow) is a design flaw in an otherwise awesome engine. I
have a plan to minimize the risk of failure in the future.

[Ben Bruce aka First Born]

Matt, I believe that number SHOULD match the one on the side. Does on my '50.  Engine was probably changed at one time, and the number on the side was ground off and re stamped.  If your number has any "1" or "6" or "9" check them closely.  The 1 should look [ and is ] like an upper case I. 6&9 should be lower case b.  This was done often in the past.   

 

  Ben

[neil morse]

Same here on the number under the water pump.  On my car, it matched the number on the block.

 

With regard to the temperature gauge, I think you are certainly better off postponing the replacement of the factory gauge.  I may be missing something, but from my own experience I would say that pulling the instrument panel and installing the new gauge is a monumental job compared to what you have done with the radiator and water pump.  Getting that panel off and back on is by far the most difficult thing I have done with my car, and that was with the front seat out and the center chrome piece and radio removed.  There is almost no room to work in there, and you will wish you had a crew of leprechauns to help you.

[Matt Harwood]

Thanks, guys. My numbers don't match at all. My engine is from a Roadmaster, so it starts with a 7 instead of a 9, but it doesn't match the number on the front. That seems odd, doesn't it? I'll double check but here's a photo of my stamping pad and it's not the same at all, even though you can't see the leading 7, which is not even close to being in line with the other numbers.

 

[JohnD1956]

4 hours ago, Matt Harwood said:

Thanks, guys. My numbers don't match at all. My engine is from a Roadmaster, so it starts with a 7 instead of a 9, but it doesn't match the number on the front. That seems odd, doesn't it? I'll double check but here's a photo of my stamping pad and it's not the same at all, even though you can't see the leading 7, which is not even close to being in line with the other numbers.

 

Thankfully that "wrong "number will be concealed under the cover of the water pump.  I suppose it could bother some that they dont match but realistically, its a '41 and who else really needs to know?

[Matt Harwood]

49 minutes ago, JohnD1956 said:

Thankfully that "wrong "number will be concealed under the cover of the water pump.  I suppose it could bother some that they dont match but realistically, its a '41 and who else really needs to know?

 

I don't think it matters any, and certainly not to me. The numbers are all stamped into the same chunk of iron so it's not like "matching numbers" has any meaning or one would have been changed for fraudulent purposes. Besides, this is not the car's original engine anyway. 

 

Oddly enough, my '35 Lincoln also has two different K numbers stamped on the one-piece aluminum crankcase (K4223 matches the serial number on the firewall and title), so I guess it happens. Nobody has been able to explain this one, either.

 

  

 

 

Edited March 1, 2020 by Matt Harwood (see edit history)

[Matt Harwood]

I didn't get nearly as much done over the weekend as I had hoped but last night and tonight I was able to get all the big jobs on the cooling system done and all that's left is dropping in the radiator and filling it up. For the most part it went pretty smoothly--I cleaned the mounting surfaces, made some fresh gaskets, and started bolting it together. My idea to use a spare piece of silicone hose was a good one, and it fit just fine with some trimming, but the part with the shrinkable hose clamps was a little more problematic. They're not quite wide enough for one to work on both flanges, so I needed one full-sized clamp and one half-sized clamp that I trimmed to fit. These are also just barely large enough in circumference for this hose--even though these are sized for 2-2.25 inch OD hoses, and the hose when installed on the water pump is 2.125 inches, it was still VERY tight. I used some dish soap and some muscle to get it all on there. It took several mock-ups and some extensive trimming of both the hose and the clamp to make it work, but eventually I got everything into place. I didn't hit it with the heat gun until I was sure everything else was right, but when I did, it snugged up just like it should. Very clean and no protruding hose clamps to get in the way or snag a knuckle later. It should also last forever. Last step was mocking up the fan and pulley just to see how it looks.

 

First up, I had to make some gaskets. 

 

Then I had to figure out the little piece of hose that fills this gap
between the water pump and the bypass housing. I didn't want
to just use a chunk of hose and some clamps, I wanted to do
something cleaner and more permanent.

 

  

I had a chunk of silicone hose left over from another project and it fit almost perfectly.

You will note that the flanges on the water pump and bypass valve are pretty stubby so 
there is not much flange for the hose and clamps to grab. Fortunately, it's sandwiched in
there so it can't really pop off. Still, I trimmed it to fit with some overlap on the
meatier parts of the castings. I also removed the "Summit" logo with some paint thinner.

 

 

Once I was satisfied with the fit of the bypass hose, I reinstalled

the bypass valve inside. I thought about using the expansion
plug with a hole in it, but since my bypass seems to be working
I decided to keep it.

 

  
Then I trimmed the hose clamps and slid everything into place. It took some soap

on the flanges to get the silicone to slide on and some trimming to get the clamps

to fit tightly, but with some pressure I was able to bolt everything in place.
Note that I'm using all stainless hardware for this installation--I know it's not
authentic, but it's not very visible and stainless works best for cooing systems.
I also used lock washers and a few drops of blue Loctite on the threads.

 

Then I hit it with a heat gun and the clamps shrank into
place to secure the hose. You can see the outline of the

flanges top and bottom, so I'm confident I have a good seal.
I may trim the excess silicone hose from above and below the

clamps just to make it look neat--it shouldn't pop off and the

clamps have a good grip.

 

  
Hose secure, I installed a new 160-degree thermostat, gasket, and housing. Note
that the thermostat is installed with the short side pointed towards the radiator.

 

The temperature sender bulb for the aftermarket gauge

under the dash was originally installed in the lower heater

port which gets cool water directly from the radiator. That's

probably why it always read a dead-steady 165 degrees.
I am going to relocate it to the upper port where it should read
coolant temperature as it comes out of the head--the hottest
point. That should be a more accurate reading, albeit higher. My

heater isn't connected so I'm not terribly worried about feeding

coolant to it, but eventually I'll want it hooked up. I'll figure out

where to connect it later. The gauge is more important right now.

 

  

And just for fun, I mocked up the pulley and fan to see how it looks. I'm using

fresh grade 8 bolts on the pulley, just to be safe. I like the contrast of the black
fan and silver pulley. 

Edited March 4, 2020 by Matt Harwood (see edit history)

[Matt Harwood]

Installed the radiator, connected the hoses, installed the temperature gauge and fitting, and started filling it up with coolant when I noticed this in my box of nuts and bolts:

 

 

Goddammit. I guess I'm done for a while with these accursed cars. I'm tired of doing every job two or three times. We'll use Melanie's cars this summer. Mine are all f*cked.

[38Buick 80C]

1 hour ago, Matt Harwood said:

Installed the radiator, connected the hoses, installed the temperature gauge and fitting, and started filling it up with coolant when I noticed this in my box of nuts and bolts:

 

 

Goddammit. I guess I'm done for a while with these accursed cars. I'm tired of doing every job two or three times. We'll use Melanie's cars this summer. Mine are all f*cked.

 

Pretty sure it the bottom side of the spring for the bypass valve, unfortunate but not the end of the world. Take a break have a stiff drink and you'll get back to it eventually. We've all been there.

[Matt Harwood]

33 minutes ago, 38Buick 80C said:

 

Pretty sure it the bottom side of the spring for the bypass valve, unfortunate but not the end of the world. Take a break have a stiff drink and you'll get back to it eventually. We've all been there.

 

You say that, but you have no idea how much time and effort it took to get that silicone hose and shrink clamps on there so cleanly. Like ten hours. Six or seven clamps. Three hand-made gaskets. Nope. I don't have the energy to do that all over again.

[neil morse]

Matt, here's an idea.  At least start it up and see how it runs.  Given the modifications that others have made to the bypass valve -- essentially eliminating it and substituting a core plug with a hole in it -- your little boo-boo might not make any difference at all in how well your cooling system works.

[John_Mereness]

Just time, at least not a major issue - hit it for 10 hours on the weekend and then project is done.  

 

By the way, these were the only two hose clamps on my 41 Super that were "modern" style and I believed when I replaced the hose I did not take assembly apart either.  And. yes, hose clamps in there always seemed to catch the hands. 

 

I am having a surprise a second putting the Auburn back together - slightly rusty at it as has been 2 years since I did last one. 

Edited March 6, 2020 by John_Mereness (see edit history)

[Matt Harwood]

Heading out there now...

[Matt Harwood]

First, a question--how the hell do you measure and size hose clamps? A few weeks ago, I called Bob's Automobilia and ordered up a set of molded 1941 Buick upper and lower radiator hoses. I also asked them to include four of the correct roll-lock clamps (which are outrageously expensive--almost $10 each). Unfortunately, the clamps aren't anywhere near the right size, they're at least a quarter-inch too large even when tightened all the way. The hose itself measures a bit over 1-7/8 by itself and not quite 2-1/8 inches when it's on the neck. The hose clamps are clearly labled "2.00 inch." But as you can see below, even at their tightest, they're considerably bigger than two inches. So when a clamp is advertised as a "2.00 inch" hose clamp, is that just a guess? Is there some different kind of inch I'm not aware of, like an Imperial gallon and a standard gallon? I had the same size problem with those Gates Power Lock shrink clamps and had to buy two 10-packs (@ $59 each) to get a set that would fit the 2.125-inch hose when it's on the neck. I figured 2.25s would work, but I ended up using 2.50-inch clamps to fit the 2.125-inch neck. WTF, guys? Is there some secret here, like take the diameter of the hose and subtract half an inch to get the right hose clamp size? Why is this hard?

 

That's  "2.00-inch" hose clamp on a 1-15/16 hose. WTF?

 

Usually I'm pretty happy with Bob's service and products, but in addition to wasting $40 on incorrect hose clamps and not being sure what size I should order to fit the hoses I do have, I think I should replace this wrinkly-looking upper hose that looks like it was made from an elephant's scrotum. At least that was only $20.

 

I'll see if I can find an elbow locally that doesn't look like crap.

 

But that all came at the end of the day. I spent about eight hours backtracking, taking things apart, and putting everything back together again. And if you don't mind, indulge me another digression. In the early 2000s, I was flipping houses on the side to make some extra money and was doing OK. I had a project house a few blocks over from where I lived and eventually decided to quit my job to flip houses full time. That particular house was a mess--it had been a drug house that I got extra cheap from the city. And because of that "usage" all the plumbing was gone--stolen and sold for scrap to buy drugs. So I re-plumbed that whole house in copper. I mean, I spent two weeks sweating joints and making the most beautiful water lines you've ever seen. Cold and hot perfectly parallel, even in the bends. Neatly arranged valves on a manifold. The inspector for the city came and said he had never seen such nice work and couldn't believe I had done it myself. I was extremely proud of it--it was something that would help sell the house. A few weeks later, someone broke into the house and stole all my copper and just tore the place apart. It was incredibly demoralizing. I set about replacing the lines, but my heart wasn't in it anymore and the second plumbing job didn't look anywhere near as beautiful as the first. Most likely nobody noticed or cared, but the lines weren't so parallel anymore, the elbows were wherever it was easiest to put them, and I didn't bother with a manifold, I just stuck the valves wherever they fit. I had reached--and passed--f*ck it.

 

So today I spent 90 minutes to drive down to Summit Racing to buy another chunk of silicone hose. Then I cut up another shrinking hose clamp and put it all back together. I suppose it's serviceable, but it isn't as pretty as it was before. I didn't have it in me to spend a few hours trimming and fitting and adjusting and fussing over it like I did last time. Nobody will notice, right? Who cares?

 

  
First run (left) vs. today. At least I got rid of the big finger print on the plastic from where I 

touched it when it was still hot from the heat gun.

 

Once the water pump assembly was back in place, I dropped in the new radiator, which fit without any issues. I taped a piece of cardboard over the core just to be safe, then bolted it into place. All the original blind clips were there and I used the factory coarse thread bolts to snug it up. At least the engineers at GM were thinking--so easy for one person to install the radiator as long as the clips are aligned properly. 

 

Fresh radiator fit without any issues.

 

With the radiator in place I installed the pulley and fan, but that's easier said than done. Don't worry, I have a little trick for that. Since you have a hub that rotates, plus a pulley and a fan that also rotate separately (that pulley really flops around), and all the holes have to line up just right to get a bolt in there, it can be almost impossible to secure everything in such a tight space. I made a little stud to help align everything and just threaded it into the hub finger tight. Then it's easy to hang the pulley and fan with everything aligned properly. Screw the other bolts into place, remove the stud, and install the fourth bolt. Easy!

 

Removable stud makes it easy to align the pulley and fan on the hub.

 

  
Fan and pulley look great with the new radiator. I also have a new fan
belt, which annoyed me because it's covered with bright green markings that
can't be wiped off with paint thinner like usual. I'll figure it out, probably
with some fine sandpaper while it's running so there aren't any weak spots.

 

I also have to decide how to connect two temperature gauges and maybe the heater. My NOS temperature gauge isn't operational so I'm in no hurry to replace it, especially after Neil's comments above. But I did note that my aftermarket gauge was plumbed into the lower water pump port, where it was getting coolant fresh from the radiator--that's why it seemed to run at 165 degrees all the time. I thought about installing the aftermarket gauge's bulb in the back of the head where the original gauge was connected (I presume it's not leaking only because the remains of the original gauge's bulb are plugging the hole) but that seemed like opening a fresh can of worms. I decided to install it in the upper port where the coolant comes out of the head--ostensibly the hottest part of the cooling system. That should be a genuine reading and far more useful for monitoring cooling system status. I installed the original heater valve in the lower port (even though my heater won't be connected at this point) just because I had it--maybe I'll use a plug later, I don't know. I went to install the gauge bulb but saw that the adapter fitting was pretty eroded. I'll need to get a new one before I can button it all up.

 

  

I installed the heater valve in the lower port. The gauge bulb wouldn't go directly
into the upper port and needs an adapter. Current adapter is pretty eroded, but
replacements are commonly available.

 

I'll order some new hose clamps this week--I guess I'll order the 1.75 inch ones for my 2.125-inch hose. Seems stupid, but the proof is up there. Frustrating to get so close and still be stymied by stupid little details. It's going to be 61 degrees tomorrow, it would have been nice to test drive the car and see about measuring temperatures on the header to determine if something serious is amiss.

 

More later.

Edited March 8, 2020 by Matt Harwood (see edit history)

[Bloo]

31 minutes ago, Matt Harwood said:

First, a question--how the hell do you measure and size hose clamps? 

 

After a career as a mechanic, I still have no idea. I never could make any sense out of it.

[JohnD1956]

Where does the other heater hose connect?  If it is at the radiator, then I do not think your heater will work very well being tied in at the lower hose like that. 

[Matt Harwood]

11 minutes ago, JohnD1956 said:

Where does the other heater hose connect?  If it is at the radiator, then I do not think your heater will work very well being tied in at the lower hose like that. 

 

The Limited's heater circuit is a little more complex than other '41s, but mine isn't hooked up. It has never worked, although all the fans are operational. I don't really know that I need heat and I never really liked 20-something feet of heater hose under the car being vulnerable. Eventually I'd like to have it working, but it's not a priority--I'm not even sure the cores are good.

Anyway, the correct way to hook up the heater is to have the valve in the upper port, which feeds hot water to the heater, and the return is the lower port. Since I'm using the upper port for the aftermarket temperature gauge, I just installed the valve in the lower port even though it's not correct there. Just a placeholder until I devise a way to make two temperature gauges AND the heater work correctly. Right now, I just want to have the modern temp gauge working to make sure it's running cool.

 

[Matt Harwood]

OK, home stretch on this project. Frustrating that I'm running out of winter and all this stuff takes way longer than it should. My list of things I wanted to get done wasn't very long, but I don't even think I'll get through half of it. Feh.

 

Anyway, I found a replacement upper hose elbow that I cut out of another hose we had laying around. Smoother and fits just fine. The lower hose fits well and I re-used the spring I took out of the old one, which I think is a good idea. I ordered new hose clamps in a smaller size from Bob's and should have them tomorrow or Thursday. I hope they fit. If not, I'll use the shrink-fit clamps and just install the roll-lock clamps over them just for the right look. 

 

This hose will look a lot better than the wrinkly one.

 

I also scored a replacement adapter for the temperature gauge.

 

While I had the radiator shroud off, I decided to refinish it. It was probably repainted when the car was resprayed about 30 years ago, and it was high-gloss black instead of satin, so it never looked right to my eye and showed a lot of chips. I threw it in the blast cabinet, stripped it, and repainted it correct satin black which looks a lot better. It's otherwise in excellent condition, although I never noticed the series of ridges that were visible after it was painted--looks like a result of the manufacturing process, maybe caused by the rollers that emboss the strengthening ribs into it. I never noticed that on my Century's shroud, either. It looks fine back on the car and isn't terribly noticeable, but I found it odd that it was so visible. I also decided that my grille emblem looks terrible with a fairly significant chip in the cloisonne finish, so I will dig out the NOS one I have on the shelf somewhere and install it, which should dress up the nose of the car a bit.

 

  
Radiator shroud painted and reinstalled.

 

I re-used most of the original bolts to secure it, but I think I'll paint the hardware satin black to match the shroud. They were probably silver cad plated in 1941 but I think I prefer them to blend in rather than look too shiny. That'll be the last step.

 

If I get hose clamps in the next day or two, I'll be driving it this weekend to make sure the headers aren't actually cooking themselves and to really test the new cooling system. Let's hope...

[Buicknutty]

Matt, great looking work, thanks for sharing it with us. I also bought what I believed to be the correct size and type of hose clamps from the same place as you, but mine are just a tiny tiny bit too small, and nothing I did would make them squeeze on. So it has modern clamps, not so authentic, but you've seen my car and it is a driver, not a show car.

Keith

[Matt Harwood]

Spent the last 48 hours in bed feeling really sick and quarantined myself in our carriage house apartment so I wouldn't infect my family with whatever I have (no, it's not coronavirus). I took Friday off from work, but after almost two days with nothing but the TV to entertain me, I started to get cabin fever. I was feeling better after lunch today so I went to the shop to work off some restless energy. I'm still not 100% but I figured 70% was enough to cross the finish line with this water pump project.

I remembered the grille badge I dug out of storage a few days ago and it was sitting on my desk when I got to the shop. That's an easy job (it just pushes into place with some clips) so I installed it first--the old one was pretty bashed up. Get a win early, right?

 

 

I was also pleased to find that my replacement hose clamps arrived from Bob's (along with another set of hoses, a replacement thermostat, and another fan belt--apparently their system doesn't clear itself and past orders will get repeated). Anyway, I installed the hose clamps, including a Grimy filter on the upper hose which you can see in the video, below. The bottom clamp on the radiator is virtually impossible to reach with a screwdriver, so I ended up using a shrink-fit clamp down there. It seems to be holding.

 

  
Correct roll-lock hose clamps look good and fit properly (use the 2-inch clamps).

 

Once all the clamps were in place, there was nothing left to do but fill it up. Since there was still about a gallon of Evapo-Rust in the engine, I decided to fill it with Evapo-Rust and let it circulate in there for a few weeks. I used my little pump to fill it up and it took about 4.5 gallons total--just about right since the system takes 18 quarts without the heater (18 quarts is, of course, 4.5 gallons). There were no immediate leaks so I fired it up. As usual, it fired easily and idled smoothly even after a few months of sitting. The long bolt through the bypass housing leaked a bit, but I stopped that one by snugging it up, and then the hose at the bypass weeped a bit but once there was enough heat the heat-shrink clamps seemed to seal it up. 

 

The good news is that the dry, whirring water pump noise that drove me to start this project was gone. The bad news is that it was replaced by a different noise that is even louder--a whine that sounds like a supercharger or a gear drive cam setup. It didn't go away with time and heat, and becomes more pronounced as I revved the engine. Crap. Is my new water pump fried? There's at least an inch of deflection on the belt so it's not over-tightened and I don't believe it's the generator bearing. I don't much feel like tackling this job AGAIN, but I started one of the other '41s sitting next to mine and their water pumps were quiet so this isn't normal. Welcome to par for the course when I'm on the job--nothing ever comes out right the first time.

 

Here's a video of the engine running--you can hear how pronounced the whirring is when I rev the engine at about 1:15: 

 

 

As long as it was running and up to temperature, I took some readings on the exhaust system. The rear cylinders are definitely 80-100 degrees hotter than the front, although I'll admit I don't know what a normal reading should be. I opened up the idle mixture screws on the rear carb which sped up the engine but didn't make it run notably worse, so I guess it's possible I've been running it too lean. The temperature readings are inconsistent, with one of the center ports running as hot as the two rear ones, and the rest considerably cooler. The head and block are nice and cool, no more than 220 degrees, the new cooling system has no problem holding it at about 175 indefinitely, but the exhaust temps are all over the place. Now I'm pretty confused.

 

I suppose it's possible that the header flows so much more air that the carbs are still too lean. But there are TWO carbs, each capable of running the engine by itself--how could it possibly be lean?. Perhaps I need to go up a jet size on the carburetors? The rear carb mixture screws are almost all the way open. It still runs great and there's no black smoke, so it's certainly not running rich. Even the tailpipe is almost cool enough to touch after a drive and there's no black soot inside the tailpipe. I'm going to use my friend's 5-gas analyzer, but I don't know whether that will help me pinpoint which carb needs tweaking.

 

Despite the noisy water pump, I took it for a long (~10 mile) drive and leaned on it pretty hard to see if the pump would "break in" or lubricate itself somehow. The car continues to drive well and makes good power--it's still really fast. There's still a slight stutter when accelerating from at low speeds, say, going around a low-speed corner in 3rd gear, but it otherwise drives like it always has. Fattening up the fuel curve may help, but I'm at the limits of what I can add with the screws. Water pump did not improve but I don't think it got worse, either. The noise is pretty intrusive and just can't be right. I think I need yet another water pump. I wonder if Bob's will take this one back after I painted it?

 

The only other thought I have is that the rear choke isn't working properly. There's an audible vacuum leak there in the choke where the little piston is supposed to close the port--is it possible that little vacuum leak is screwing up the mixture? I'm tired and feeling crummy again, but if I feel better in the next few days I'll pull the rear choke and see if I can seal it up. 

 

Disappointing, but I'm too sick and tired to keep working today. I'm going to go take a nap.

 

[kgreen]

Good luck with it.  I'm afraid you found the very definition of frustrating.

[Aaron65]

Regarding the exhaust temps, I think you might be worrying needlessly.  Every engine feeds cylinders unevenly; dyno tests have shown that there can be a one point difference in air/fuel ratios from one cylinder to the other.  Jetting will not change your idle EGTs.  You aren't running on the main jets until the car's going at least 40 mph, so you'd have to increase the size of the idle jet, which would really have to be accomplished by pin drills, and then you're in "you had better know what you're doing" territory. 

 

Check for vacuum leaks, and set the idle mixture screws based on engine vacuum.  There are a few different schools of thought on this, but I've always just tuned for the most vacuum.  Some will then turn the screws in a little for "lean best" idle, but at that point you're probably close enough either way.  Good luck!  

[EmTee]

I would put some miles on the car and read the spark plugs; they won't lie... 

[JohnD1956]

First observation from your video is that the head has consistent temps front to rear. If there was an imbalance in the engine causing the temp differential in the headers I would think that would be reflected in the head temp at the back.  So, the 2nd observation from the video is that there is less airflow at  the back of the engine likely due to the length of the motor and the presence of the all the peripheals between the front two header leads and the rearmost header leads. 

The 3rd observation deals with the whine. That doesnt sound like the waterpump from my viewing window. I wonder if it is the fan belt. Did you use anything to listen directly to the pump. Some use a long screwdriver between the unit and the ear. But a mechanics stethoscope is my preferred method. Got mine at the NAPA for less than 10.00. You can really hone in on noises that way.

Edited March 15, 2020 by JohnD1956 (see edit history)

[edinmass]

You can put the car on a five gas machine, and tune it correctly. I would put it on a chassis dyno, and tune it at idle and at speed. With a custom exhaust, modern fuel, dual carbs , ect.......it’s the best way to set it up for a final tune. I would be sure to run it fat,  fix the air leak, and put 100 miles on it before you do any final tuning. Also, the carburetors should have been rejetted and the air bleeds recalibrated for modern fuel, as well as placing the distributor on a Sun Tester and checked for proper function. I would also recurve the advance tip in for initial and overall advance. I would run a hotter plug than stock........two or three ranges hotter. When you get it all done, I’m gonna come out and visit you and go for a ride..........I expect to be in you area a several times this and next year......so your gonna get to see more of me than you will want...........I’ll stop by with a few of our cars.........they will also be in the neighborhood. 😎👍
 

Fun engine I was playing with last week......1913

Edited March 15, 2020 by edinmass (see edit history)