VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 Spark plugs

Hello USA!
When did the Chevrolet began to use small plugs.
Are there 3/8" thread or 10 mm?
Bengt From Sweden

Chevrolet used {AC No.104}, and {AC M8 Plugs} starting in 1941 thru 1948. They are 10mm.

The passenger car engines used 104 in 1941 and 1942.In 1946 the 104 was replaced with the much improved M8....was also used for replacement in 1941-42 cars...all had 10MM threads.

I realize this relates to much later models but when did they start using the tapered seat plugs?
We started seeing them about 78 in GMH but I think some others were using them a few years before.
Tony

If I remember correctly the first tapered seats used in a Chevrolet engine was in the big blocks in 1970.Was used in small blocks in 1971.Eventually all engines.

F*#d used them in 1955.

I have found an engine whidt small spark plugs.
Do the engine fits in a -37 sedan?
Are there 235 ci in this engine?
Can I use -37 gear case?

Bengt From Sweden

The 1941-47 engine with small spark plugs will fit in a 1937.You can use your present transmission but-if you use your 1937 flywheel , the flywheel will fit only a 1941 engine (4 crank shaft mounting bolts)...if its a 1942-48 engine it will be necessary to use the later 6 bolt flywheel and clutch (much better clutch) and the front shaft inside the transmission will need to be replaced with one from a 1938-39 3 speed..,and the 1938-48 starter must be used.
The engine will be a 216 unless it came out of a heavy duty 2 ton truck.

There are an four gear case on it so it must be
an 2 ton truck engine.
I have not purshased the engine yet.
Vhat do you think are that a good purshas or not.
Are there much job to have that engine in my -37
sedan.
Bengt From Sweden.

The 4 speed transmission could have been in any size truck.So the engine could be a 216 or 235.Would need the casting number from the side of the engine to identify.Either near the fuel pump or behind the starter.The truck flywheel housing (bell housing) would not fit up to a car transmission.If its a 1942-48 engine you would need to find a flwheel,clutch,front transmission shaft, and bell housing from a 1938-48 car plus the later 1938 clutch linkage.Could be a problem in Sweden.

I will look for the casting number, it will take
a day or two. i am back later.

Bengt From SWeden

It is could here in Sweden now but I vent to the garage and look for casting #.
I foud (OON 4 or CON 4 or GON 4) K15.
Are that right number?
It seems to be a very tuff job to install this engine.
Bengt From Sweden

The casting number will be something like this-

3660439,3693374,3835335,3835353,3835309 (and more)

I put a 1948 216 engine in to my "38". My "38" engine was badly worn and as I happened to have a good "48" engine, and as everyone told me that it was a "better" engine I installed it.
It will go in so long as you use the later flywheel and clutch.
There are some problems. The later engine has a different oil sump because it has a different oil pump. The sump slopes down to the rear whereas the early engine slopes to the middle. The early cars have a crossmember that supports the transmission and the later engine will not clear and will hit on the crossmember. I modified the shape of my crossmember to allow it to clear. In the later cars they do not have the crossmember; only the ends .
Another thing is the inlet manifold. The early engines sit flat whereas the later ones do not. If I had used the "48" inlet manifold in my "38" the carburettor would lean forwards. Fortunately the manifolds can be changed over.
Be careful with the starter. I tried to use a 48 starter with a solenoid and it got in the way of the clutch pedal so I had to use the "38" starter with the foot pedal starter.
Take care.

Putting the engine in a 1937 is much more difficult due to the type of clutch and flywheel used in 1937.Would be especially difficult to find the needed parts in Sweden.

Thanks for advise.
I hesitate now and I will think about it.
There must be another engine for sale here in Sweden I have to look for it.
The problem at my -37 engine is that the block has been frosen at the inlet/outlet carburator side and welded.There are no leakage now but I
have not started the engine yet.I have to wait
and see and look for an 1937-1940 engine.
You are so wonderful all of you.
Bengt From Sweden

There should be no problem running the engine with the welded carack.It could leak a little at that area but will cause no harm.
Try to find a 1937 thru 1940 engine.Would be handy to have if you ever need it.

I hope you are right.
We will vait and se.
Thanks for help.

Bengt From Sweden.

Hello chevgene!
We have found the engine number now.
The number is: GM 3 3835849.
Can you ansver what year the engine vas made.

Bengt From Sweden

According to my list, you have a '52 passenger or half ton truck 216, or a '53 half ton truck 216. I'll check my '52 truck later.

3835949 is the casting number for the replacement 216 engine sold for use in 1941-53 cars and trucks.This engine was sold thru parts for replacement...not sure if it was used in production.

Thanks for answer.
Are there the same condition for install the engine in a 1937
sedan car?

Thanks for answer.
Are there the same codition for install the engine in a 1937
sedan.

Yes-the 1938 and later flywheel and flywheel housing and clutch parts must be used.

I have found an other engine #399910.
What year are that engine made (1937-1940 perhaps.

I do not see a 399910 number.There is a 839910 which is a 1942 to 1947 engine.It also has the 6 bolt flywheel.
The numbers for the 4 bolt flywheel engines are -
838101-1937 block
838710-1938 block
838914-1939 block
839132-1940 block
Your 1937 head will also fit any of the above.

839400-1941 block
Can use any 1941 thru 1953 216 head with this block

A 1941-53 216 head can be used on the 1937-40 blocks ONLY IF THE LATER FLAT TOP PISTONS from a 1941-53 ARE USED.