After removing and disassembling my engine due to a flattened cam shaft, I can't seem to find the VIN number anywhere. The only readable numbers on the front engine pad are 10L there may be another letter right after it but I can't quite make it out maybe 8 or B. The previous owner, whom owned it since '71 told me that the block was not decked when he rebuilt it a few years ago. The casting numbers on the back of the the block are B 4 70. I have the build sheet and it list the engine as an L34. Do these numbers give any indication that this is the original engine to my car? VIN 183444

The previous owner also told me that the tranny is not the original that it was replaced a few years back with the one I currently have. The information listed is P9T16B and 19S711921. I believe it is an M21. My car came with an M20. I appreciate any information you can provide.

I use a tire crayon to try to bring out faint stampings. Rub it over the area where the numbers should be and wipe it gently with your finger, leaving the crayon in the stamped depression. The cast date is close to when your car, #83,444 would have been built, but without "finding" the vin number on the pad, it may be impossible to ever know for sure. The 10L = 1 being Chevrolet..0 being the year, 1970...L should be plant of final assembly, Los Angeles. The vin should follow the three that you can read. There should be a 1 and then the faint 8 followed by the rest. Good Luck!!

70,
I have seen some big blocks with the numbers stamped on a pad on the side of the block, drivers side if I remember correctly, above the starter. You may not be able to see tham with the engine in the car.

10L is part of the VIN derivative

1 - Chevrolet
0 - 1970
L - Los Angeles assembly
rest may have been stamped so lightly as to not show up or the engine block was decked. Common with many quality rebuilds. He many not think is was decked but it many have been.

The alternate location for the VIN is left side of block, on vertical rough surface rear engine flange, near oil filter.

The tranny is not original to the car, the VIN derivative does not match you serial number.

I tried looking elsewhere for the numbers but couldn't locate any, I guess that was it. The engine was not decked as the previous owner did the work including the machining that's what he does for a living.
I heard of a process with some chemical that brings out the numbers if there, has anyone heard about this?

I have a 70 350 which also has no vin on front pad but thereis a stamping that reads 10 C 7 i posted this a while back and no one knew what it meant. did they possibly just date stamp some engines not knowing what they would be going in?wasnt there a strike around this time?

Begining in 1968 all the auto manufacturers started stamping VIN derivatives on engine, transmission, body and frame.

For people to claim this is normal is not correct. They made over a millions cars and trucks every year at GM. I am sure there were many workers not doing the job they were paid to do.

There are a lots of reasons why you don't find it.

-Engine work obliterated it
-Engine is not the one it came off the line with, weather the assembly plant had to replace it, the dealer or someone else in the chain of ownership.
-Worker said the heck with it & inspector let it go
etc


-

Trans info:
P=Muncie 4sp
9=1969 model year
T=Dec(68)
16=day of month
B=M21
Partial vin:
1=Chevy
9=69 model year
S=StLouis assembly plant
711921=sequence number
StLouis with 7+ vin sequence is Corvette

Rene
66_Malibu

There is a process that is used with chemicals that "raise" the numbers on metal. We in the law enforcement field commonly use it to bring back serial numbers that have been ground off on guns.

Freddy, are these chemicals readily available to the general public? If so, do you know where one can find them and which ones? smile.gif

I am looking at a 70 ss chevelle that is supposed to be #s matching, but the seller says that the number is stamped upside down and it isn't centered, is this common.

READ THIS ONE NOT THE PREVIOUS ONE!!! I am looking at a 70 ss chevelle that is supposed to be #s matching, but the seller says that the number on the engine pad is stamped upside down and it isn't centered, is this common.

My neighbor has been in Dealer service programs since back then. He had worked for a large Chevy dealer in the area and has explained to me that there were a large numbers of dealer installed shortblocks and long blocks back then. Guys would buy these cars and literally leave the parking lot and thrash the daylights out of them. I am not saying this is what happened in your case, but it was very common. Things like overheating, detonation, over reving were all common place. Many a car was back in for warranty work within 90 days of delivery.

My guess is that motor was freshened up and the block was decked. My own '71 block required a .008 cut to reduce the height at the #2 cylinder alone. Then it was cut another .004 to clean the entire surface. .012 and numbers are gone completely. If the vin is not on the block, the next best thing is verify the date code which should preclude the car build date by about 3 months.

Check above the oil filter, vertically, in the rough casting. I've seen two Chevelle blocks stamped with the vin # there.

He does have part of the VIN on the block, 10L is it, someone did not strike the hammer hard enough for the rest (183444) of it to show. Probably hurt himself in the process.

People always say VIN but the VIN was never stamped, a VIN derivative was stamped and its would be 10L18344 and nothing more. I realize most of you know this but I am sure they are just as many who do not, as evidenced by some of the questions I get asked. BTW-The VIN derivative is also known as the Confidential VIN (Con VIN) in police and insurance lingo.

These were gang stamped and here is an example of what they used.. You can see that it would have been easy to stamp the code up-side-down. In fact there have been a lot of them found like this and documented at correct. If someone was going to forge one, they would be sure to get is perfect, you would think?

http://www.synthetic-oil.com/images/EngStamper.jpg

One way to tell if the block has been decked is by looking for the original block surfacing marks from the factory. (Called Broach marks I think) The factory block surfacing left longitudinal grain marks - from front to back. Most machine shops use a different machine that leaves a different pattern of marks on the block surface.

The machine's GM used was a production type and was very expensive as it was used to cut raw blocks. So no machine skop would likely have such a machine, nor would they care to have one unless they were in the business of duplicating GM machiniing...