The Stovebolt Site Forums The Shop Area Engine Shop Is this a 302 GMC engine?

Hey evryone, I know that I can check the seriel number but its been a long day and thought maybe someone could identify this engine just by looking. This engine has a two barrel carb, the machanical fuel pump was never mounted (casted over from factory so must have been electric) the engine has an air compressor mount casted on the right front and it has the oil filter in the back, not front. The engine has Military paint on it. Is this an M-211 302 or could it be a late model 270 also? Thanks for looking!

Well, I can't tell from the video. It is in a CCKW chassis, so originally it would have had a 270. It does not appear to have the sealed distributor the military 302s had,but that could have been changed. As far as I know the military 302s were the only gmc engines in that family that were not cast with a fuel pump on the side.

So it may be a 270 or smaller engine, or a 302 with a delco distributor.

From the year of truck looks like a 270 ,just my best guess .Like you said to really know you will have to read the numbers.

Military GMC 302 engine pictures
http://www.alfaheaven.com/MilitarySection/Engines/G21.html

The GMC 270-cubic-inch (4.4 L) 270. It was produced from 1941 through 1962 and was an OHV/pushrod engine. This is a raised-deck engine.
The 302 GMC inline six was produced from 1952 to 1960, when it was replaced by the V6. It has a 4.00" bore and 4.00" stroke. Connecting rod length was 7.000". This is the largest raised-deck engine. It was originally designed for the GMC military M135 and M211. It was used in military 2.5 ton trucks with the HydraMatic transmission, however the engine was a sealed engine for snorkel/submersion use, had an electric fuel pump, and other features such as a deep sump oil pan. From 1952-1959, GMC manufactured the civilian 302 engine which was not sealed, had a mechanical fuel pump, and used a "standard" oil pan.

By the looks of the age of the truck, I would think it would be a 270. The 302 didn't come out until 52 and it would have had a sealed ignition and a Holley carb. Look on the distributor boss. The first 3 digits of the engine number will be the displacement. They will be stamped, not cast.

I'd say there's a good chance it had a later 302 swapped in but you would probably have to check numbers to be sure. All of the 1.5 tons (single drive axle) I've seen have been the Chevrolet versions so I would guess it's not original to the truck. My '42 Chevrolet military truck just has a 216 but it works fine to plow snow and move stuff around the farm.