Corvette Forum : DigitalCorvettes.com Corvette Forums banner

1 - 10 of 10 Posts

·
Registered
Joined
·
41 Posts
Discussion Starter #1
I am trying to see if my motor is original,I don't think it is. Am I looking in the right spot for the number? All I can find is on the block, almost where the tranny bolts on, on the driver side and it says "3970010" and theres no VIN stamped next to it as the other posts say there should be. Im guessing I am in the right spot and its just a different engine. Any thoughts???

Thanks!
 

·
Registered
Joined
·
5,206 Posts
I am trying to see if my motor is original,I don't think it is. Am I looking in the right spot for the number? All I can find is on the block, almost where the tranny bolts on, on the driver side and it says "3970010" and theres no VIN stamped next to it as the other posts say there should be. Im guessing I am in the right spot and its just a different engine. Any thoughts???

Thanks!
3970010 is known as the casting number and that number is correct for 1975 thru 1977

The number matching part is a seperate number located on the passenger side front and the flat pad were the head to block joint is. This number is "Stamped" not casted like the other number you found

this number for your car should start with

"V" for made in flint
the next (4) numbers are the build date
first two month
second two the day of the month

then the number should end in
either CHA , CHb, CHC, CHR, CHU, CHZ, CKC, CPU, CRK, CRL, CRM, CUA, CUB, CUD, or CUT these are all vailad codes for 1975

Your build date needs to be earler than the build date of the car to be correct (the motor cannot be build after the car. How far ahead is the gray area

Hope this helps
 

·
Registered
Joined
·
2,002 Posts
Check the pad on the block at the front of the right head. AC compressor and/or AIR pump might be in the way and you may have to clean gook off the pad. You will find two numbers stamped there; larger characters will be the engine identification number. Smaller characters will be the VIN derivitive of the vehicle the engine was originally installed in.

Hopefully, the VIN derivitive on your block will match the VIN on the windshield post.

Here's what you're looking for: 74 shown; 75 will be similar.


:thumbsup:
 

·
Registered
Joined
·
41 Posts
Discussion Starter #4
ok

I have found a pad similar to the one in the picture (thanks for the pic by the way!!) and there is nothing on it. It's nice and clean, no gook etc and no numbers. Am I to be looking over the motor from the top I am assuming? Sounds stupid but the extent of my "old Car" knowledge comes from my 1974 VW Bug I had in highschool..... 20 yrs ago.
 

·
Registered
Joined
·
2,948 Posts
Yeah that number would be visible from the top.

Sometimes it takes some mild cleaner and a soft abrasive of some kind to clean the pad. The numbers hide quite well under many years of dirt and grime.

Also a possibility, is that at some point in the past, the block that is in your car...stock or not, may have been to a machine shop and decked.

Generally a decked engine has also been rebuilt. Do you have any records of the engine in your car being rebuilt or repaired?
 

·
Registered
Joined
·
41 Posts
Discussion Starter #6
Hey D_B!

So, How bout them Rams :)

The guy I bought the car from did not know squat about this car. He thought he did but was sadly mistaken. He was really vague about the details of the car but did tell me that the engine was "new"..... He didn't pass along any receipts or anything like that. He also tried telling me it only had 13000 miles on it which just by looking at it was an obvious mislead. Incidentally I found a receipt in a box of stuff he gave me for a used speedo that had been installed..... Long story short I think the engine has been rebuilt at some point. The machine plate is very easy to locate, painted black and is as clean as a whistle and smooth as a baby's ass... The rear of the motor has a casting number that shows it a GM motor (3970010) with a date stamp of G 12 8 which would make it July 12th 1978 right? So right off the bat its not the original motor since the car is a 75. I would still like to find the vin stamp just to see what car it was put into, vette V.S Chevy truck or Van etc...
 

·
Registered
Joined
·
41 Posts
Discussion Starter #7 (Edited)
Does anyone know of another location on a small block that chevy might have put the numbers? I have found the machine pad on the front of the motor just below the head and it is pristine. So What now? Is this the end of my search? Do I give up? I have read online that they were put above the oil filter and one that said its on the pass side, below the head and the alternator might be blocking it...... my alt is on the other side.:WTF Also if this motor was made for another GM car would the numbers be in a different place, such as a truck or van?
 

·
Registered
Joined
·
2,002 Posts
...The machine plate is very easy to locate, painted black and is as clean as a whistle...G 12 8 which would make it July 12th 1978 right?...
Or 88. TargetMaster replacement engines can be painted black; the pad would show no numbers.

The alternate location for stamping a Corvette VIN derivitive was on the block near the oil filter. That location was only used in the very rare circumstance of not being able to get a legible stamp on the pad.

I'm guessing you have a TargetMaster 350 replacement engine installed prior to the owner you bought the car from. He said the engine was "new" when he bought the car.

:thumbsup:
 

·
Registered
Joined
·
41 Posts
Discussion Starter #9
Heres an update

So I found a sticker in the engine compartment from Jaspers remanufactured engines. I emailed them the number on the sticker and they replied! The were able to tell me the engine is in fact a remanufactured motor and was installed in 2004. Based on what I do know about the car that means it only had about 5K miles on it. So, sounds like I am in good shape for the most part.
 

·
Registered
Joined
·
2,002 Posts
Wonder if Jasper remanufactured the original engine? I'm not familiar with how Jasper works, but it might be possible to ship your orignal engine to them, have it rebuilt, and them ship it back to you.

:thumbsup:
 
1 - 10 of 10 Posts
Top