VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 '32 engine start-up

This is so much fun.

Last week I posted that I had dropped the oil pan on my recent-purchase '32 engine and discovered that the rear oil relay and tubes were in the sludge in the bottom of the pan. Since then, I cleaned everything up and turned the engine upside down and figured out how to fabricate (bend) new tubes and installed them. I first tried to use a modern epoxy to hold the tubes in the relay, but that didn't work because I didn't rough the outside of the tubes enough for the epoxy to grip

I went ahead and soldered everything as original and I now feel a lot better about the repair. I turned a 1/2 inch pice of round stock on the lathe to make a tool to use to turn the oil pump once I took the distributor out. I stuck the oil pan back on and filled with 10w-30. Turning with a hand drill I got about 30 pounds of oil pressure and it was a hoot watching the oil work its way out of the holes in the top of the rocker arm shaft

Once I had oil pressure I said "Why not?" and wired up a coil and sprayed gas down the carburetor throat and spun it up. It started!

Next step will be to rig up a fuel pump to get a steady supply, and hook up hoses for coolant so I can run it for a while to get to the point where I can do a compression test.

I forgot to mention that while I had the pan off, I pulled the rod caps on cylinders 4, 5, and 6 (the ones where the relay was messed up), and everything looked good.

Like I said, this is so much fun!

Tom

As long as the oil feed lines are correctly aimed at the gutters that feed the troughs you should be safe.

Yes, that was a real concern. I carefully marked the pan and lined it up with the block and adjusted the tubes to the marks on the pan. I have a new gasket set ordered and when I get it, everything comes apart again for at least cleaning and painting. The compression test will tell me if I have to go to the complete rebuild. I have not yet taken the head off, but when I do I can check valves and bore taper.

When I drop the pan again I'll be real careful to keep it level to see what oil is in the dipper troughs.

Tom

It's hard to believe that it's been a month and a half since my last post on this subject. The slower I get the faster time goes by.

In any case, I took the head off this '32 engine today and measured the cylinder bores. The shop manual tells me that the bore originally was 3 5/16ths or 3.3125. My measurements were between a low of 3.355 and a high of 3.361 with the vast majority right at 3.357 or 3.358.

The bores were very smooth with almost no ridge at the top. None of the bores had a pronounced taper. Do those measurements indicate an overbore? 26 or 27 thousands over seems like a strange number.

Does anyone know the end gap specs for the rings in this engine? If I pull the pistons and take the rings off and measure them what should they be?

I'll take the head to the machine shop shop on Monday and get it cleaned and magnafluxed. The last head I took in was bad enough (cracks) that the shop said it wasn't worth rebuilding. Hopefully this one is OK.

Thanks. Tom
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Hastings recommends a gap of .0035 per inch of cylinder diameter. I would measure it with the ring at 3-4 heights in the cylinder bore. That translates to .012 with a max of .020. according to their chart. If my math is correct you are about .040-.050 over not .027 or .028 . The cylinders I believe should be measured top, bottom (below ring travel) and middle.

USUALLY the pistons will be stamped on the top if they are oversized. Will be like .030 or..

Thanks for the ring end gap info. I think the last Studebaker I did the ring end gap was between .013 and .026.

Yes, I measured top, middle, bottom twice at right angles (just the way the engine sits in my garage I did east - west and north - south).

You are absolutely right about the math. This time I did it with a calculator instead of in my head. I don't know how I got so far off. So most likely a .040 overbore? I guess I don't really worry much about that as long as the rings do their job sealing.

This is the first old Chevrolet that I've owned. I am really disappointed in the shop manual and parts manual. For example, the shop manual shows an illustration of cutting valve seats, but doesn't say what angles should be cut. Is it a multiple-angle cut or single? One of my friends has a real nice valve seat cutter set that I've used on other engines, but the shop manual for those makes told me the angles.

I can't even find actual clearances for main and rod bearings.

It is very frustrating, but enough of that rant for now.

Is there any place I can find all this type of detailed information in print so I don't have to keep coming here and probably asking questions that have been answered a hundred times before I joined the club?

Thanks. Tom

I'll scrape carbon tomorrow and check for oversize markings.

Thanks. Tom

The repair manual doesn't give details like modern manuals. I think that is because most repair shops and shade trees didn't have accurate measuring devices or tools. So torque specifications are "tight", etc. Tolerances are often determined by how well parts fit. For example adjusting rod bearings by tightening and tapping with the ball-peen hammer. The cap should move with a light tap but not with your finger. That was more appropriate for the "mechanics" of the time. FYI, we have learned that rod and main bearing tolerance is 0.001"-0.002". Gaps larger than 0.002" can result in excessive oil leaking past the rear main bearing. Rods greater than 0.002" can give a noticeable noise.

The valves are single cut. 45 deg. angle.

Thanks Chipper. I think I'll just start a notebook where I can write stuff like this down when it comes up on the chat, so when I need to refer to it I won't have to search through old threads or ask repetitive questions.

The pistons are indeed marked ".040", so it looks like my measurements were very close, and now I know what I'm dealing with if , for example, I wanted to buy new rings.

Tom

Just be aware that the original '32 rings were thicker than replacements. The change to thinner rings was partially complete in 1933 (pistons and ring sets one year only). Competed in 1934 the pistons and rings (1934-'36) were used as replacements for the '29-'33 Chevrolets. Just be sure you know which pistons you have before ordering rings.

I had the opportunity to spend almost a full day last week with Frank Hug, Jr, in Arkansas. What a great day. Frank was really gracious, and it was great to tour his shop and see the Hug family collection of antique Chevys.

We talked about a great number of things and Frank had many of the service bulletins that were much more specific about specifications than the shop manual. He made me a copy of specifications published in 1932 that answered just about every question I had here.

He showed me some things that relate to RHD cars only, and while I know that my roadster was brought back to the US in the mid-eighties from Argentina, I had not considered that it was brought back for the body only. I could not find anything on my chassis to indicate RHD. Suddenly I had an epiphany. Some poor 4-door sedan in south Texas had given up its frame to the roadster body. No wonder that the Argentinian title (from 1971) had a different engine number than the import papers and from what I got as an engine when I bought the car.

Again, a fabulous day with Frank in Arkansas.

Tom