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Hey Everyone,
This new engine situation really has me stumped. The water pump in my '42 3/4-ton special died. I ordered a pump from Jim Carter that should have been correct(41-53 Chevy) What I got looks like this . It doesn't, however, match my old one which looks kind of like this , except it's old and rusty and has a pulley.

The mounting holes don't line up; The intake on the new one comes in clockwise above all the mounting holes instead of counter-clockwise between two of the mounting holes; The outlet doesn't line up and the whole thing's about a half-inch taller. In short, it's totally different. I would say that Carter sent me the wrong piece, but it looks like American classic has the same thing.

So now I'm wondering if I have a different engine than I thought I did. I thought I had a 216, but that was only based on the 2-stud valve cover. Did early 235s have the same cover? I looked for an engine block casting number, but couldn't find one. All I found was the stamped serial number, which is T3795778. Does that tell me anything? Does it make a difference that this is a canadian truck? I've seen that canadian GMCs sometimes used chevy engines, but what about canadian chevies? Also, there's a casting number on my old water pump, which is 598309. Does that help?

I hope somebody can shed some light on this. I just want to find a water pump that will fit and get my 'bolt back on the road. Thanks

The babbit pounding 235's looked pretty much identical to the 216's from the outside. I don't know anything about the water pumps on a 235, so I can't help you there -- my apologies.

That serial number you gave us looks more like a casting number (which I can't find). Is it off of that pad just aft of the distributor, or is it cast into the side of the block? It is possible that the serial number is different for Canada. I'm not sure what -- if anything -- is different.

You could also follow the instructions on the Tech Tip to see if maybe the tell-tale signs are there.

Hopefully Fumblin' will saunter through and give some sage advice.

The serial number I gave (T3795778) is stamped into the flat spot just behind the distributor. I couldn't find any cast numbers. Some of the posts I searched through said it's by the starter, but I just don't see anything there. Does the starter maybe have to be removed to see it? The only cast marking I can see on the block is 'GM', which is below and just in front of the distributor.

Here's one more piece of the puzzle. I just noticed that Chevs of the '40s has a pump that appears to be just like my old one, here , but it says that it's for a '39 or '40. Might my engine be older than the truck?

Jon:

Anything's possible. These trucks are old and they've withstood aeons of abuse, which has caused many an engine swapout. If your truck has a history similar to mine, then it's entirely possible that the PO bought the cheapest running engine he could find and dropped it in.

My truck has had 5 engines in it. The engine that's currently in my truck was originally out of a '49 passenger car, via a '52 pickup that got t-boned. Grandpa got it for cheap and he and Uncle Skeeter did the swap in the driveway in the dead of winter. (History is fun!)

There should be a casting number down on the block or oil pan (can't remember how far down it is) and it'll be towards the radiator under the draft tube and the fuel pump. It's usually a six or seven digit number. There should also be a date code near the starter.

If the engine is older than 1946, then I don't have a serial number decoder chart that will work. I am fairly certain that all of the blocks came out of Flint or Tonawanda, but, since your engine might be Canadian, the numbers could be different.

Hopefully someone who in in the know will come along and enlighten us.

Jon,

I'm pretty new at this but I found a web page on Hemmings that might shed some light on your number behind the distributor.

http://clubs.hemmings.com/clubsites/chevytalk/GMhistory/1933motors.html.

According to this info the T prefix would designate it as a truck and the number
3795778 seems to fall into the July 1933 production numbers.
The 216 was not introduced until about 1937. Perhaps you have a 207? Someone with more knowledge than I will have to help you with the definitive ID of your engine.

Perhaps you can email a picture of your old waterpump to your supplier and they can help ID the pump for you if the engine was really built in 33.

I hope this is a step in the right direction.

Randy

This should get you there without the period at the end of the address.

http://clubs.hemmings.com/clubsites/chevytalk/GMhistory/1933motors.html

Randy

So, It's MUCH older than we thought.

Wow. A real live 207.

Impressive.

If it is a 1937-40 chev engine it will only have one water transfer hole on the back plate of the pump. 1941-54 has two.

Jon, give us the casting # from the head, this will help to identify the block also.

Your truck is not a Canadian model is it? Canadian GMCs used the 224, a close cousin of the 216. I just pulled the old 224 out of my 1940 Canadian 1 ton (which is the same as a US 3/4 ton special).

Steve

Wow!
Now I am really confused. 1933 to 1942. 207 to 224. What the heck is this beast?

Pre-68 Dave My old pump only has one hole on the back. Check out these pictures:
Pic1
Pic2
Pic3
Pic4

These are what I sent back to Jim Carter, along the the pump which clearly won't work. The incorrect pump in the pictures is for a 41-52 216. So does the single hole on the back definitely identify my engine as a 37-40?

41 Chevy: Where on the head do I find the casting number?

Steve: Yes, my truck is Canadian. Was the 224 used in Chevys, or just GMCs? Also, I had thought my truck was a 3/4-ton special based on the leaf spring count and the 17-inch wheels. Are you saying that's called a 1-ton for a Canadian truck?

You definitely have a 1937-40 style pump.
There were some changes as to pulley positions in those years. Give me a measurement from the back plate to the back edge of the pulley and from the back plate to the fan flange and I can tell you which pump you need.

The link that Randy provided to the Hemmings/Chevytalk site is for US engines. The Canadian numbering was similar, but different. Elsewhere on that site is a huge Word document containing info for Canadian engine serial numbers.

The info around '40, '41, and '42 is a little unclear in that document for the T-prefixed 216 truck engines, but I think that 3795778 may have been sometime in late '41. The Canadian engines may have continued use of the '40 style parts longer than the US engines. The Chevy 224 engines used in some Canadian vehicles (GMC trucks and Pontiac cars) would have a different prefix.

My parts books show the 598309 pump as being from a '37 or '38 with pulley number 838764 or from a '39 or '40 with pulley number 838905.

The Canadian 9400 series is considered a 1 ton. 17" wheels, big rear end and brakes. Mine is a model 94-23 on the data plate. 94=1 ton, 23= body style (in my case a pickup). I have both a 1940 US Chevy shop manual and a 1940 Canadian GMC shop manual. Comparing he specs, the 3/4 ton special appears identical to the Canadian 1 ton. The Canadian GMC used the 224, but I believe the Canadian Chevy used the 216.

Steve

BTW, my 224" serial # is TT15949

You might find the Canadian GM site useful for more info:

http://www.gmcanada.com/english/maintenance/parts/parts_vint.html

What model does yoru data plate indicate?
Steve

Steve,
I've never been able to find a vin decoder that works for my truck, so I don't know the model for sure. My vin is 2943301345. I just concluded 3/4-ton special because of the 17" wheels and because of the number of leaf springs.

If I recall correctly, your VIN breaks down like this:
2=1942
94= 1 ton chassis
33 - body style (not sure which)
01345 - serial number


Steve

Your pump is exactly like my 38 216. I ordered a rebuilt for mine through my local Parts Plus jobber. It was about $70.

In the casting,forging or stamping ID number listing for 29-42 it is listed. It is the same pump I have on my 216, 37 pickup but my engine was swapped out over the years and it is a 42.