Matt Harwood

1941 Buick Limited Limousine

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Posted (edited)
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.

 

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Edited by Matt Harwood (see edit history)

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Posted (edited)

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.

 

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First up, I had to make some gaskets. 

 

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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.

 

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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.

 

 

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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.

 

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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.

 

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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.

 

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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.

 

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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.

 

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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 by Matt Harwood (see edit history)
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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:

 

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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.

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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:

 

191811113_20200305_1651521.thumb.jpg.0b97d31206d39348a65dce02d9b2a6e1.jpg

 

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.

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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.

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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.

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Posted (edited)

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 by John_Mereness (see edit history)

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Posted (edited)

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?

 

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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.

 

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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?

 

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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. 

 

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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!

 

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

 

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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.

 

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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 by Matt Harwood (see edit history)
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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.

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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. 

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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.

 

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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. 

 

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

 

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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.

 

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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...

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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

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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?

 

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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.

 

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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.

 

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

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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!  

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

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Posted (edited)

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 by JohnD1956 (see edit history)
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Posted (edited)

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

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Edited by edinmass (see edit history)
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Posted (edited)

First off, @JohnD1956 nailed it--the whirring sound is the belt! I would never have expected that, but to test his theory I installed the old one and it sounded exactly the way it did last year when I thought the water pump bearing was going bad. So I installed a new water pump I didn't need, but it's all new so I never have to worry again. I reinstalled the new belt, which, while noisy, at least has a more pleasing sound--more of a supercharger whine than a bad bearing grind. I did some searching online to see if I could cross-reference the Gates belt from Bob's, but it appears that this toothed belt is the only one with the proper specs. My friend at the auto parts store actually found an old book that lists 1941 Buick Limited fan belt part numbers and found one in his system, so he ordered it. It will be a few days since it's coming from Arkansas, but we'll see what it looks like when it arrives. Oh, yeah, it's $50. Maybe I'll live with the sound. Either way, big thanks to John, who nailed the diagnosis from 500 miles away--nice!

 

Second thing I did was disassemble the choke on the rear carb and do some reading in the manual. it's a complex little mechanism that's more than just the thermostatic spring--there's a little piston in there that is supposed to be pulled into position by engine vacuum, and that's what provides the resistance for the spring to push against. As the spring relaxes, vacuum pulls the piston deeper into the port, exposing it to atmosphere and releasing pressure on the choke blade. You may recall I went in there once before, but after reading about a special tool that's used to set the piston position (which, of course, I don't have) I looked carefully at the diagrams and realized that I had it set in the wrong position--that's why it flooded and why it had a vacuum leak once it was up to temperature. I reset the piston's location relative to the choke blade shaft and not only did the choke relax faster but the vacuum leak disappeared. Hopefully I'll get one more cold day where I can leave it outside for a few hours and see if it's still difficult to start cold, but I am optimistic that I got it right this time. The front choke will be doing most of the heavy lifting now.

 

6-6-19-6.thumb.jpg.4f7eb743107bcb477e3acc49059b465a.jpg  6-6-19-10.thumb.jpg.6a85488ef1e4eada88d8111199cdf479.jpg
Position of the piston inside the choke housing is important (these photos are from the first
time I rebuilt it). Getting it right seemed to improve operation.

 

Once I had the choke set back where I believe it should be, I printed out the suggestions earlier in this thread from John and CarbKing and did some additional tinkering. I disconnected the linkage and tuned the two carbs separately by ear until I got a nice, smooth idle and a clean exhaust note. I ended up fattening the fuel curve quite a bit and then took a longish drive. The Big Guy drives like it always has and I now do not believe anything was seriously amiss with the tune--it just runs too well and pulls too hard to have any serious issues going on. The stumble remains, which I believe is an ignition issue (more on that in a moment).

 

Oh, and with the hood off, it's easy to see how much the engine moves around--I have some new engine mounts around here, so I guess I'll install those. And there's quite a bit of what appears to be steam coming out of the oil breather on top of the valve cover, mostly under load. It could be blow-by, but it's clean with no residue on the valve cover or splashed on the windshield. I'm thinking it's just moisture evaporating from the oil and I just never see it because the hood is there. My car does not have the recirculating tube from the valve cover to the air cleaner, so perhaps I'll drill a hole and add an EGR pipe when I pull the valve cover to adjust the valves.

 

Anyway, after the test drive, it was as hot as I could get it (it's about 50 degrees ambient and with the new cooling system--and no hood--it was running at 165 or so). I attached a vacuum gauge to the port on the intake manifold and did some additional tuning. I should have done this a year ago, but I was lazy. The engine has very good vacuum at idle and was able to get it to stabilize at about 24 inches of mercury with all four screws tweaked. The video below shows the process, which is simple: just turn the screws until you get maximum vacuum that's STABLE. I started with the rear carb and turned in one screw until it started to flutter, then backed it out again (making it richer) until vacuum reached its highest value and the needle was not wiggling. Repeat for the other screw, and then for the front carb. I didn't do any voice-over, but if you watch the gauge, you can see each of the four screws being adjusted in this brief video:

 

 

I still plan to use my friend's 5-gas analyzer as @edinmass suggested. I might even be able to find a dynamometer to use--I used to work for a dyno manufacturer and know a lot of the tuners who bought our equipment. That should give us an even clearer window into the tune, but I still have a few more details I want to address before we get to the final stage: new plugs, new ignition components, and resetting the timing to base. I set it to about 4 degrees advanced beyond factory spec a few years ago when I first started driving it and I've moved it around since then, so who knows where it is now. I believe the timing is the source of my low-speed stutter.

 

Today I used a vacuum pump to verify that the vacuum advance in the distributor was working correctly, which it is. I lubricated the various parts in there and the rotor, points, condenser, and cap all look fairly recent, but I have all new parts so I'll install those, set the point gap properly, reset the timing, and set the dwell before I do any more carb tuning. I'll also pull the plugs and give them a read, a job I'm loathe to do simply because getting the plug wires back behind that side cover is a real PITA. 

 

I was exhausted and I still feel pretty sick, but I was enjoying some success so I didn't want to stop tinkering. Last job was fixing the horns, whose wall-eyed orientation has always bugged me. I pulled them off and realized that whomever installed them didn't merely reverse them, he also changed the location of the mounting studs to get the horns to clear the fuel lines. I had to remove the domes and switch one of the mounting studs with one of the little studs that sandwiches the assembly together around the perimeter. Once I did that, the horn dropped into place and faced the right direction. I did the same for the other side. While I had the domes off, I sprayed the little electromagnet with some contact cleaner and blew it off with light compressed air. The wires were apparently custom-made to fit the horns in their walleyed orientation, so one was very long and one was almost too short once I reversed the horns, but with a little tweaking I was able to make them fit and not look too hokey. 

 

1497625849_2020-03-1516_25_31.thumb.jpg.378bc9a0f4478ddbbd10bba73901aa6b.jpg  615571022_2020-03-1516_25_40.thumb.jpg.7630f844926c0e48fb9dd79df1a9f8b4.jpg
I had to swap the mounting stud and one of the little perimeter studs to get the horns
to face forward.

 

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The horns were a little dirty inside, so I cleaned them up.

 

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Reinstalled and facing forward, which also gives me a bit
more clearance for the fuel lines. No idea why
they didn't get it right the first time--its like swapping
them side-to-side didn't even occur to whomever was
installing the horns in the past...

 

Going to do some more driving, tackle the ignition system, and adjust the valves, maybe as soon as next week. I have a hunch it's going to be quiet around the shop for a while. I hope we can weather this storm--our overhead is substantial (I don't want to let my employees go) and it makes me very nervous. I don't think we can survive for more than a few weeks if people stop buying cars. Yeah, I'm worried.

 

I'm also exhausted. I think I'm going to get some dinner and go to bed. Maybe I'll be less worried when I'm not so tired.

 

 

Edited by Matt Harwood (see edit history)
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Matt, the hesitation you are talking about.......we call it “a tip in” hesitation, when applying the throttle. Check you accelerator pumps, that they are operating as intended. Also check float bowl levels. Sounds like you 95 percent of the way there already. I really enjoy the super fine dial in of any pre war car..........making them start and run like a modern fuel injected engine with 70 year old technology. Our most recent car we dialed in to the “100 percent” potential is a Model J. It actually starts better than my new Ford. It’s actually amazing how well it fires off...........Such a great feeling of accomplishment when the car is dialed in. 👍👍👍

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28 minutes ago, edinmass said:

Matt, the hesitation you are talking about.......we call it “a tip in” hesitation, when applying the throttle. Check you accelerator pumps, that they are operating as intended. Also check float bowl levels. Sounds like you 95 percent of the way there already. I really enjoy the super fine dial in of any pre war car..........making them start and run like a modern fuel injected engine with 70 year old technology. Our most recent car we dialed in to the “100 percent” potential is a Model J. It actually starts better than my new Ford. It’s actually amazing how well it fires off...........Such a great feeling of accomplishment when the car is dialed in. 👍👍👍

 

It's not quite a tip-in hesitation--I know what you mean. It revs cleanly from idle or tipping into the throttle at speed. What I get is a stutter when, say, I go around a corner and leave it in 3rd or even if I drop down to 2nd. I can drive through it by giving it a lot of gas, but it's not a smooth transition. I don't know how else to describe it, but accelerating on a roll from closed throttle to half open causes it to buck somewhat. 


Great throttle response, but a bit of bucking under modest acceleration at low speeds. I'm still leaning towards too much ignition advance, which is why I needed to test the vacuum advance (which actually retards it at low engine speeds/high vacuum) and why I need to reset the timing. 

 

To be honest, this is the one drivability issue that bugs me the most. Of course, I still have a few rattles to solve, but that's an ongoing thing...

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Went in to the shop to work today, feeling better but really tired. Both kids also sick now. School canceled for three weeks. Melanie stayed home with the boys today. Quiet, but we did get a few calls which makes me feel better. I need to sell some cars so we don't starve.

 

Anyway, on my way out the door this evening I walked past the Limited. I reached in and moved the throttle linkage to unload the chokes. The front one closed all the way while the rear one only closed about halfway. Reached in the window, turned the key, and pressed the button. Vroom! Started instantly and idled smoothly without any assistance from me. Temperature was about 55 degrees in the shop, so not very cold but cool enough. I'm hopeful that my choke adjustments have been successful in alleviating the hard start when [very] cold. One more really cold day and I'll park it outside for a few hours to really chill it and see what happens. 

 

Of note, the front choke did not reset to the highest part of the high idle cam, just the middle setting. I think that's probably acceptable. Easy enough to fatten it up if necessary.

 

I also realized that despite my attempts to build heat stoves into the headers, they don't really direct all that much heat to the chokes so they are very slow to respond. I had it idling for about 10 minutes and the front choke never opened fully and the rear choke didn't move at all. On the road and a hood in place, I still think it will be sufficient. 


Going to order a new valve cover gasket for adjusting the valves this weekend--there's a pretty persistent tap from cylinder #2 so an adjustment is a good idea. A few more upgrades and it'll be ready to tour as soon as tour season starts (whenever that might be) and then I can jump back on the Lincoln--still aiming for Hickory Corners in August for Lincoln's 100th birthday party.

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Matt, I just discovered this thread and have read through page six since not much else is going on these days. Very impressed with your work and your unflinching coverage, I am subscribed.

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