Jump to content

Rebuiding a 1931 90 Series Engine


Recommended Posts

Well ladies and gents I am going to start to reassemble my engine over the next month or so. Going to go slow and clean. It will take a little longer because I want to scrub the newly machined block down and the weather is not cooperating out here in Pennsylvania.

I will post pics as I go along with what I'm doing and what I'm running into since I did not find much information when I was struggling with this motor (though I did find lots of help here when I posted questions).

Anyway I bought the Buick 4 or 5 years ago, running and rust free but showing its age. It ran OK, but had weak compression and overheated regularly. After a cosmetic restoration I started to drive the car and it had less and less power and overheated no matter what I did, flushed the block, re-cored the radiator, pulled the water jacket cover and cleaned it out etc. Worse it started making noise. I dropped the pan and pulled a main cap and discovered the babbit was starting to spall. I made the decision to get the block checked, machined and re-babitted.

Using suggestions from this forum I had Reeves Enterprise do the machine and babbit work (very nice people). I decided to do the assembly. I like to learn new things and this will be my first prewar engine.

First I pulled the head and found the cooling passages almost completely blocked with loose scale. Then I pulled the engine and tranny together. Heavy but doable. Hint- I suggest you pull the steering box and shaft if you are going to pull the engine. Then off to Reeves it went. He found two small cracks in the block which were repaired and some old repairs to the head so I hope this thing holds together. I had to have new pistons made, and decided to have the connecting rods machined to accept inserts.

I have the newly machined babbitted, and balanced engine back so as soon as I get it cleaned and start assembly I'll post pics and what I did.

Wish me luck.

buick Engine.jpg

P4060026.JPG

PB060039.JPG

  • Like 4
Link to post
Share on other sites

I tagged along with midman to get his engine. The one they are working on for my 1925 is still underway.

 Here he is with Patrick Reeve . He may be thinking...    "What have I gotten myself into"?

DSCF6582.thumb.JPG.7a30d18938e2400413e29c3c7501e0dd.JPG

Freshly machined and balanced crankshaft. Much heavier than the head I helped carry.

DSCF6583.thumb.JPG.f7855eede7454ad0105a028b52ca52e6.JPG

 

 

  • Like 5
Link to post
Share on other sites
  • 3 weeks later...

Well the cold weather that hit here set me back since I wanted to get the block outside and wash it down thoroughly before beginning assembly.......Still waiting for it to be warm enough.

In the meantime I assembled the pistons and connecting rods and installed the piston rings. Reeves machined the rods to take inserts. Hopefully not something I will have to deal with again in my lifetime but done all the same.

 

Conn Rod Inserts.jpg

Piston Assembly.jpg

Piston Parts.jpg

  • Like 3
Link to post
Share on other sites

Wow, talk about a loooooong stroke! Those connecting rods look like they're more than a foot long! I have never had a 344 engine apart like this. They are monsters to lift--done that before but don't want to do it again anytime soon. You hope and you pray and hope that your engine hoist won't tip over!

Pete Phillips, BCA #7338

  • Like 3
Link to post
Share on other sites
  • 2 weeks later...

Well, It got warm enough to get the engine thoroughly washed down!! Finally.

I decided to put the motor together on a heavy duty table I made because this thing is just too darn big for my engine stand. It lays on its side cam on the high side. We picked up the crank with the engine lift and swung it "gently in. Worked well.

I installed the pistons and pushed them through first since the big end of the connecting rods are bigger then the engine bore and I did not want to deal with taking apart the harmonic balancer and screwing around with installing them from underneath after installing the crank. It worked great. Pushed them through, installed the crank then pushed the pistons back through as I assembled the connecting rods to the crank.

Installed the cam no problem.

Next step will be installing the cam gear and bellhousing and flywheel (that's why the rear main is still off. I need to get to the crank flange bolts when installing the flywheel and bellhousing. Then the cam followers and oil pump and oil lines and buttoning up the bottom end.

Camshaft.jpg

Pistons rods.jpg

Crank Install 1.jpg

Crank Install.jpg

  • Like 5
Link to post
Share on other sites

Concerning your engine cleaning, this is required after the block is returned from the machine shop to make sure there is no tramp oil, metal particles or grinding debris remaining anywhere inside. But I would have thought that both the oil passages and coolant jackets would have been cleaned thoroughly before the machine work was done. The last thing I'd want would be for any residual sludge being blasted out of the oil galleries and onto a bearing surface or a nicely honed cylinder bore.

Link to post
Share on other sites

Don't you just love the counterweights on the crankshaft!!!

 

There are very few oil galleries in the block.  there is a passageway from each main bearing up to the cam bearings,  two ports at the oil pump to and return from the oil cooler, and a fitting through the block  at the rear right side for oil to filter and cyulinderhead.  Oil distribution from the pump to the mains is by way of a copper tubing manifold.  

 

Bob Engle

Link to post
Share on other sites

The pistons were made by Ross. I could not find original pistons standard or oversize anywhere. I did find a couple sets of oversize piston pins. Ross will need the pins along with the specs to machine the pistons. Not cheap though. Over $100 each

  • Like 1
Link to post
Share on other sites

Carl,

We did discuss compression. Originally I was looking at putting an overdrive unit in and bumping the compression to make the car more tour friendly, but after some thought I kept coming back to the shortcomings of mechanical brakes and decided to keep the car a back road tourer, so I kept the pistons at the standard profile. 

I do have the overdrive unit if I change my mind once I start driving more.

Chuck

Link to post
Share on other sites
  • 2 weeks later...

Well the front gears, cam roller assemblies and oil pump are installed. Next will be the oil distribution manifold (This manifold uses copper sandwiched gaskets that I could not find so I'm using the old ones), bellhousing and flywheel and front cover as well as the oil pan. I am going to install the engine without the head to help with the weight, hopefully next week it will be back in the car.

P4110001.JPG

P4110003.JPG

P4190007.JPG

Link to post
Share on other sites
On 12/04/2018 at 11:19 PM, midman said:

the shortcomings of mechanical brakes

Can you enlighten us on these shortcomings please? Henry Ford was adamant they were as good as hydraulic and continued with them well past when others had gone hydraulic. They must be in good adjustment though.

Link to post
Share on other sites

https://www.wikihow.com/Lock-Wire-Drilled-Head-Bolts  I would assume this is the proper way to wire any pair of bolts/capscrews, not like the third picture of post #15.

 

I do not believe there are any shortcomings with mechanical brakes.  When set up correctly you can park the vehicle for any period of time and they are ready to work correctly when needed.  From 50MPh I can lock all four of my wheels with half a pedal.  Without locking the wheels I can stop from 50mph in the length of my head light beams.  I adjust my shoes every 20,000 miles ( 2 years ish) or so and usually get 70,000 to 85,000 miles on a set of linings.  The only limitation I see is the number of square inches of rubber to the road which has nothing to do with actuation of the brakes either hydraulic or mechanical.  One thing for sure with mechanical brakes you will never burst a hose and the chances of breaking a cable, clevis or rod is very low and at the worst you would only lose braking on one wheel.

  • Like 3
Link to post
Share on other sites
1 hour ago, Tinindian said:

I would assume this is the proper way to wire any pair of bolts/capscrews, not like the third picture of post #15.

 

YES! As it is at the moment, the left bolt will undo the right bolt if it comes undone and the right hand bolt will pull on the LH bolt if it comes undone and make it more likely to undo.

Link to post
Share on other sites

Now you see one of the reasons I post this stuff. Thanks for the helpful feedback. 

When I tore the engine down that is how the bolts were wired. In fact the oil manifold in the pan was wired like that too. I know this engine was repaired in the past though so it can certainly be incorrect.

I’ll do some more research and rewire the cam follower housings if that is the correct procedure.

 

As far as the mechanical brakes go, you are probably correct in that the surface contact size of the tire is minimal compared to today’s cars, being the biggest issue to better braking, but the fact remains that I decided I am not going to drive 70 miles an hour on the interstate with this car so I did not bump up the compression. In my opinion hydraulic brakes are better, but that is more because they are easier to maintain and more consistently apply equal pressure to each wheel without lots of adjustments.

 

 

  • Like 2
Link to post
Share on other sites

I also want to throw a question out there. The cam gear retaining bolt had some damaged threads. I cleaned up both the male and female but I am concerned about putting too much torque on it. I tightened it to 20 ft pounds with red thread lock but I’m not sure that will do it. Any thoughts.

 

1FE197AA-FB4A-46A2-9D9B-C01A646BC317.jpeg

Edited by midman
Spelling (see edit history)
Link to post
Share on other sites
1 hour ago, Spinneyhill said:

They didn't have torque wrenches in 1931. A good mechanic would tighten it until it felt right.

 

All the old timers I knew used to tell me they tightened things "goodentight".

  • Like 1
Link to post
Share on other sites

Sorry this is a late note, but I thought about using inserts instead of babitted connecting rods.  On the connecting rods, the original design is babitted main end caps and  the wrist pin is bolted tight to the connecting rod.  There is babbiting on the sides of the big end of the connecting rods.  This keeps the wrist pin from working it's way to the edge of the piston and into the cylinder wall.  On a modern engine, they use c clips in the end of the wrist pin bore to keep the wrist pin away from the cylinder walls.  The insert bearings are narrower than the connecting rod.  Did they do something to prevent the wrist pin from floating into the cylinder wall when they installed the inserts?   Did they put the insert into the babbitt and leave the babbitt on the sides?  

IMG_5367.thumb.JPG.8c41a1af7c2b709a37b561bd95746eb1.JPG

Link to post
Share on other sites

Here is a bolt torque chart.  I am not sure what size your cam gear bolt is.  Hardware may not even be grade 2, so maybe look at these as maximum specs.     

I also wanted to share this head bolt tightening sequence in the second image.  It seems like a strange one to me.  I am used to starting on the inside and working outward.  Wondering what your plan is.  I also think that they are a little aggressive on the torque specs in the second posting.  Hugh

5adba9825af34_bolttorquespecs1.thumb.jpg.ae1471a4041293c560c224acec91db28.jpg

5adbaae08a9bc_torquespecs.jpg.d9b385e84885bf01ee2ac9ba0326246a.jpg

Edited by Hubert_25-25 (see edit history)
  • Like 1
Link to post
Share on other sites

Hugh,

You can see the inserts in post #6. The rods and caps only have a couple of thousands clearance against the crank as you can see in post #8. I really didn’t discuss how he machined them other than I told him to go ahead with the inserts.

Chuck

  • Like 1
Link to post
Share on other sites

Spinney,

I had one of the rod bearings off but neglected to get the number before I installed them. I'll try to get them from the machinist and I'll post it here if he comes through.

 

On ‎4‎/‎21‎/‎2018 at 5:27 PM, Hubert_25-25 said:

Did they put any shims under your main bearings?  What did you use for your rear main seal?   Thank you.   Hugh

Hugh,

No shims on the mains. I used 5/16 rope seal on the rear main.

Chuck

  • Like 1
Link to post
Share on other sites
  • 3 weeks later...

Well , I was just about finished buttoning up the engine when I found two pieces I missed. Rule number 1 make sure you have everything cataloged .

Anyway one piece was a threaded plug for the rear of the cam (add 4 hours or work re-tearing down the bottom end, bell housing flywheel, etc.)

The other part is this small plug which I can not find where it goes. The machinist removed it but he does not remember where it came from. It is just .48 in diameter so I am assuming it is in the oil galley lines but I cannot find an obvious location. 

I am not going to button this up without finding its home.

Any ideas out there.

7602A226-1E3C-4D89-874F-DFCA205671F3.jpeg

Link to post
Share on other sites

The only things applying thrust to the cam are the oil pump gear and the crankshaft drive gear.  I believe both of these gears force the cam to the rears to maintain contact with the cam thrust plate.  There should little in the way of forces that will work on the retaining bolt.  

 

The factory was not concerned with the bolt coming loose or they would have pinned it or wire locked it.  

 

Bob Engle

Link to post
Share on other sites

The brass plug that you is looking for a home,  could it be part of the oil temp regulator system.  there are springs that may have been retained by that plug.  Just guessing on my part as I only know the 50 series engines.

 

Bob Engle

Link to post
Share on other sites

Seems I had the answer to the wayward plug on my computer all along. No one knew where the plug went so I was stumped. I had gone over that block 50 times looking for where the plug might go.  Then I remembered when I bought the car I also got a pile of blueprints, so I figured I better start searching. I had donated the plans to the Buick Heritage Alliance and they gave me scanned copies. I went through every engine print I had, blown way up and started searching, inch by inch,  and there it was.

It was on the rear main bearing, I had been scouring the block. So after installing it I started reassembling again and  I'm almost back to where I was 2 weeks ago. So glad I didn't have to tear it down any further.

 

Plug.JPG

Missing Plug.jpg

  • Like 2
Link to post
Share on other sites

OK, Got a bunch of work done.

Reinstalled the bellhousing, flywheel, oil manifold, front cover and oil pan.

Installed the pilot bearing and clutch and the cylinder head. New head bolts, not high crown bolts like the old ones but this engine has been apart a couple of times at least so I was not comfortable reusing them.

Rebuilt the rocker assembly and started installing the pushrods.

Unfortunately I found a pushrod with some damage I missed on disassembly. I am not comfortable installing it so I am trying to track one down. hopefully one of my sources will have one. The pushrod spring cap was a little mangled so my guess is it was cocked on installation sometime in the past allowing it to rub against the rod.

Oh well, the install is stalled again during the hunt.

Cylinder Head 1.jpg

Cylinder Head 2.jpg

Pushrod.jpg

  • Like 2
Link to post
Share on other sites
  • 4 weeks later...

Midman:

 I spoke with Patrick Reeve today. He said that ROSS will be shipping my pistons by the end of this week. So they will be probably be getting them back in my engine by the time we get back from the Buick nationals. 
I mentioned your push rod issue and Patrick indicated that they have a source for just about any push rod.

  • Like 2
Link to post
Share on other sites

C Carl:

I have not had any contact with them. The Reeve's gave them the piston and the oversize to match up to. Correct compression height offset pin bore etc. But now much lighter in aluminum. I let it up to the shop so I would not micromanage their expertise. (Usually slows down the process). I just wanted the correct application for the engine. Still, it did not matter as it has taken more than 5 months to get the pistons. The engine has been out since last September. My Master developed a knock right after we pulled the Standard engine. I have refused to investigate until I have the Standard driving again.

Link to post
Share on other sites

You guys sure have had a series of unanticipated setbacks. Sometimes it just feels like system overload. Great patience you two display. But then again, in this hobby, there is no alternative. You know that tremendous feeling of satisfaction when you finally fire them up and take to the road. I have done so after too, too long ;  tears of joy streaming down my face!  Courage !   -  Carl 

Link to post
Share on other sites

Well, after what seems like forever I think I'm ready to swing the motor back into the car next weekend. Installed the clutch which I did nothing to, as it looked brand new with good discs, springs and levers. Installed new throw out bearing. I shimmed up the closest bearing I could find and a new pilot bearing. 

Rockers all gone over and with the replacement pushrod (thanks Roger!) and pushrod spring cap (I fabricated one from 24 gauge steel) the head is pretty much done. Upon closer inspection of the old spring cap, I see that parts of it had broken away which very well could have been what killed my mains and rod bearings that were damaged.

I can't find my cylinder head to rocker oil line. I am going to have to make one up I guess. I bagged and tagged everything I thought but it is not there. Anyway I can swing the block in without it.

Transmission mounted. I just have to finish up all the bolts. 

I had removed the engine with the steering column in, big mistake. It should be much easier now since I removed it for resealing the steering gear.

Hope my engine lift can handle it. I installed the head so I could work on it without killing my back, but it is going to be a lot heavier than when I pulled the engine. Back then I pulled the head separately.

 

Engine ready1.jpg

Engine ready2.jpg

Edited by midman (see edit history)
  • Like 2
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...