The Stovebolt Site Forums The Shop Area Engine Shop Casting number 3837004 not only 55-57

I have a 1949 3100 bought new by my grandfather. I know for a fact this truck has never had a motor swap. the casting number is 3837004. The serial number (behind distributer by oil dipstick tube) prefix is BGCA http://chevy.oldcarmanualproject.com/models/engine.htm#49eng
with a build code of J108 (Oct 10th 48). This truck was ordered by my grand father with blue exterior/red interior with a heavy duty clutch and 4 speed floor shift/ dual action shocks front and rear/ dealer installed oil filter, and 2 taillamps. He passed this on to my father who has passed it on to me. I work for GM and asked our corporate rep about the casting code 3837004 wich was also used between 1955-57 on the 235-261 with the serial number including T56X. production started in later 55 for the 56 model year with over production units being put into earlier 57's. My 49 is titled by the serial number on the motor. I would be more than happy to post pics of the number on my title matching the serial number on the block with the casting code and production code. I wonder how many motors have been changed due to lack of research. It seems to me that the serial number behind the distributor is more important and will tell you more than the casting number 3837004

T56X refers to:
T = Tonawanda engine assembly plant
56 = 1956
X = regular production 3100/3200 235 truck engine

The 56 would not have been used until 1956 but a 1956 engine might have been installed in a early 1957 truck.

3837004 (reference: Inliners) was used on 1955-57 235 truck blocks (Becks, shows this as 3738004, but I think that is an error). Do you have a reference for it being used on a 261 block?

You state: "I wonder how many motors have been changed due to lack of research." What does this relate/refer to? Engines being changed at a later date, out of convenience/necessity (when a replacement engine was needed)?

The original registration/titling might have been done based on the engine serial number (ie: BGCA) or by the vehicle serial serial number (cab-plate code), depending on the year, on the state, on the knowledge of the dealer/DMV when they first registered the truck.

Your truck has most likely had an engine swap (memories fail all of us over a 60 year period).

Does the valve cover have 4 machine screws on the sides or two bolt/nuts on the top?
There are other certifiably distinguishing characteristics between an original 1949 engine and the 1956 engine that you have. Are you able to post photos? We can request photos of specific engine parts, if you are interested.

One final consideration: I have an engine that has had the original engine serial number removed. Also, replacement Chevrolet engines might have come with no engine serial number. This would allow a shop/owner to stamp the replacement engine's bock with an engine serial number that would match title/registration.

so Skip, you're saying the '49 216 engine used the same block casting as the 55-57 235?

Bill

I still wonder if the engine wasn't changed and stamped by the distributor with the number on the title when installed.
Does this engine have a full height side cover.

This is what I would bet on.

Thanks for all the reply's. This is what I was hoping for, so I get get a little better information. The truck has 1800 miles on it. It has been garaged more than driven. I know that doesn't mean alot, I see new motors going into new vehicles all the time. The motor has 2 bolts going through the top of it. the side cover is not full height. I can post pics later this evening when I get home. As far as me saying " I wonder how many engines have been changed do to lack of research" means just that. I have read alot of people saying they are or have changed there engine because of the casting number 3837004, and I'm just wondering if they really needed too. I probably should have worded my initial post a little different, now that I read it myself it sounds like I have a stack of documents in front of me and I know everything. Wich believe me isn't the case. I am simply looking for other opinions on this topic. It made no since to me that my motor has all the characteristics of a 216 but has a 235 casting number. I have been researching and asking questions for the last 8 months and everything I find seems to be condradicted by another website or document. Our GM rep will be in again this month and I will see about getting some kind of documentation from him to back up his statement of the casting number being used more than once. The T56X engine according to him started production in late 1955 to be put into the new 56 trucks, at the end of the 56 production schedule the "left over" motors GM had wer also put into some 57's until the "overstock" was used. I understand that the Serial number could have been restamped on the engine behind the distributer, but that doesn't explain the build code J108 (Oct,10 of 48) is what I'm assuming this would mean. Either way with this casting date the block would have had to have been built in 48 or 58, and I find no record of the 3837004 casting being used in 58 (or 59). This where I'm stumped. I don't understand the configuration of numbers and so far the closest I've come of making sense of it is to believe what the GM rep told me.

What is the casting number on the head? I think that would clarify the situation for you.


Kurt

I am pretty sure you will find the "J108" will end up being Oct,10 of 58 not 48.
A 1958 block will have provisions for side mounts.
Also, a two bolt valve cover can be used on any 235.

Here are locations of various head and block casting codes.

The date casting codes will tell you when the head and block were cast. These codes plus the head and block casting codes will tell you what engine you have (and, when the head and block were cast).

216s and older 235 (1941-1949 235) engines have very similar characteristics. Can post photos? If yes, take close-up photos of where the water pump attaches to the block. If it is a 1954 and later 235/261, and the water pump is the original style, the water pump body will be completely below the head.

Also, all 216 engines and all pre-53 235 engine had an oil-distributor on the manifold side of the block.

If you provide enough information, people will be able to tell you what engine you have.

Finally, if you simply want to quickly determine if you have a pre-1953 engine or a 1954 and later engine, take off the valve cover and count the number of head bolts (15 bolts on all 216s and on earlier 235s, and 18 bolts on later 235s and all 261s).

You mention a "build code" of J108. Is that a casting code? If it is, that is the day when it was cast. The engine "build" for use in a specific vehicle took place at a later date.

As Pre'68 Dave posted above, that might indicate a casting date of Oct 1958 or Oct 1948 or, I guess, Oct 1938.

If you cannot easily post photos, tell us the location of the water pump, tell us if there is an oil distributor on the manifold side of the block, and also tell us the number of head bolts.

OT

Do you have pics of interior?
Sounds like a nice truck

@ DADS50. The blue with red interior is not very good looking in my opinion. If it wasn't handed down I would be changing this.
As for pictures, I have all kinds, but can't figure out how to post them.

The J108 is casted in the right side of the block back by the starter. The letters are raised.
I looked at the link posted by tclederman with the oil distributer on the side of the block and my block does NOT have this. So according to this, my block would be post 1954.
This still doesn't explain the 3837004 with the J108, even if it is a 1958 motor, according to everything else I've read.
I asked my dad if he was aware of the truck ever having a motor change and he doesn't recall either. I would like to know myself though. I have pondered tearing the truck down and repainting it. It's solid as can be and wouldn't take much. There's no metal work to be done, and I hate the colors, however if it is an original motor, i would leave it be and just leave it in my garage until it was my turn to give it to my daughter. In the same breath, I think it would be kind of cool if each generation would put there personal touch on it. Kind of like a time capsule.
Anyway I appreciate everyones time and input.

I will need to check the sales brochure, but I have never seen a red option offered in 49 for the interior color.

Skip49,

No matter what year engine you have, if it has no oil distributor, there is no possibility that it is the original engine.

There was no factory option for red interior for 1949 USA Chevrolet trucks. Supposedly just about any paint combination could have been special ordered, but that might have only been for exterior colors.

Do you have your pictures on an on-line hosting service?
Here is a free service: http://picasa.google.com/features.html#utm_medium=embed&utm_source=pwalogin

Tell us what on-line photo hosting service you have and someone will let you know how to post links to photos.

Im glad to hear your going to leave it as your GrandPa had it.
Look forward to seeing the pictures.

Thanks

A thought, maybe the original block froze and cracked, then was replaced buy a new one later. Still could have used the original head, you said it had low miles.

Skip49,

Will you post a pic of the serial number.

Also, what is the casting number on your cylinder head.

All I can say is way to go Grandpa for nearly doubling your power with the engine upgrade and customizing the interior to your liking without a family member catching wind of it. Those that repeated “That’s the way he bought it” bought it.

Curt makes a direct hit with his comments.

Except for the exaggeration (for reasonable affect) about doubling the HP from a '49 216 (90 HP) to a '56 235 (140 HP) = a ~50% improvement. This is indeed an improvement that any of us would accept with a big smile.