VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 29 Chev Engine assembly

Hi all,
I'm helping a friend of mine assemble a 1929, 194 CID engine. I've worked on countless engines over the years but not one of these. The gasket kit seems to be lacking seals that go between the panel and the head, on the right side of the engine, at the holes where the spark plugs go through the panel. It would seem to me that without these seals, the blow-by vapors will make a mess of things, as well as allow contamination to enter. My friend has a service manual, but not a parts book. We have the engine assembled except for this particular panel. The engine was all in pieces when he got it so he doesn't know if there was seals there, or if there should be.

I've checked through all the post in this category and didn't find the answer, so I'm hoping a reader can help us out.

The 1929 engine had no vents on the valve cover and was designed to vent through the spark plug holes.
In 1930 the valve cover was improved and had vents, they then fitted cork seals around the spark plug holes.
Your engine should have no seals around the holes for the spark plugs.

In 1929 there were 2 versions, First Generation, then Second Generation.

First generation had a sealed valve cover and almost flat push rod cover with open air around the plug ports. Problem, moisture got caught up in the valve cover and caused it to corrode/ rust out, and all the dirt getting it around the plugs. this is what i have

1929 First Gen Push Rod Cover w Plugs
1929 First Gen Plug Port Close Up
1929 First Gen Valve Cover Top
First Gen Valve Cover Bottom

Second generation, they went with a 3 vent valve cover and a more contoured push rod cover with sealed plug area.
These are from a 1930, but Similar as on Second Gen 1929

1930 Push Rod Cover & Valve Cover
1930 Valve Cover Vent Close Up

The first generation '29 engine has the crankcase vent air intake around the spark plugs, the air and vapor exit through a hole in the rear drivers side of the block to a vapor/liquid separation device and finally through a tube to the air cleaner. That system uses a non-vented valve train cover. The second generation has the air intake through the slits in the valve cover, into the crankcase and out through the oil fill tube to a separate tube to the air cleaner. The oil fill tube is located 1/3 of the way back from the front of the engine on the drivers side. That same system was used on 1930 engines.

It addition to the crankcase ventilation differences there also was a carburetor change from a short large diameter accelerator pump to a smaller diameter longer pump. It is common to find that some of these differences have been changed in the nearly 90 years since manufacture.

The cut off point for the change from first generation 29 to second generation 29 engines seems to be around mid May 1929. My early June 29 still has the non vented valve cover, no side cover seals, but the lower rear drivers side draft tube hole in the block is not drilled. The vent tube that went from the bee hive looking rear draft tube in the early model to the carburetor, was moved to the oil seperator/oil fill tube in the second generation 29. That change was carried into 30 and beyond. There are a few minor internal engine modifications you may want to consider before fully buttoning up and installing your engine. These will improve the reliability and longevity of what you are doing.

Thanks fellas. That's all we need.

Kinda weird though, that GM eventually calculated that those three small slits on the 1930 valve cover would be adequate compared to the volume of the spark plug hole vents.

Thanks again.

"There are a few minor internal engine modifications you may want to consider before fully buttoning up and installing your engine. These will improve the reliability and longevity of what you are doing."

beachbum; The engine belongs to a friend of mine who may already be aware of them, but what are the modifications that he should consider? He likes to have his restorations done as close to original as possible, but he has been known to exercise some flexibility.

He will be bringing the crank and rods to my shop in a few days to have me check the fit, so I can mention the mods to him at that time.

Here is a shot of my Engine: Drivers Side of Engine
Notice the Oil Filler Tube also has the return to the intake on the carb.

Close Ups of Engine
Oil Filter / Separtor
Boss for Separator

Previous VCCA discussion about Boss and Generations: Oil return tube on the oil separator early 1929

Thanks BearsFan315
What I'm looking for is the 'internal' modifications that beachbum referred to.

The modifications I would recommend have to do with the oil pump and the rod bearings. The oil pump on the 29 is essentially a hold over from 1928 and is very small. The oil pump impeller is only about 1/2" thick, the outlet tube is 3/16" copper tube and the fitting into the block is only 1/8" pipe thread. I would recommend at least upgrading to a 30/32 oil pump, change the outlet tube to 5/16" copper tube, and drilling out the fitting to 1/4" pipe. The original block fitting, and tube really restrict the amount of oil that goes into the distribution tubes for the connecting rods, and the main bearings. I am assuming the connecting rods are original. You should cut an oil groove in the connecting rod babbit that will allow oil to be directed up to the holes in the top of the connecting rods. If you have not done so already - clean out the "sediment pockets" above all three main bearings. Try to be careful and not get crud down the main bearing oil tubes. I did these minor modifications on Mike Larsens 29 and the oil pressure went to 25psi fast cold idle and 7psi hot idle. It was essentially 0psi before. These are very inexpensive fixes that will make a big difference. Keep us posted on your project.