I didn't notice this yesterday when I pilled my motor. What does this mean? Was the engine a warranty replacement or is there somewhere I can look up the history of this 350? The engine has a casting number of 1241748 ( I think 72 350, it's a 72 skylark). Head numbers are 1243452. Motor looks clean and has 95,000 miles. Any ideas? Thanks
The engine was rebuilt by a machine shop. If you knew what shop it was you could probably call them with the job number. Depending on how far back their records go. Look at the freeze plugs and see if one of them has a small silver disc glued on one of them The engine should have the last six of the VIN stamped on the machined front face of the block next to the timing case cover. Service manual says passenger side.
Yes inside the head under the rockers it says GM 1233452. I did find a little disc on both sides of the motor glued inside 2 freeze plugs. They just say guarantee void if removed. Thanks Jason!
Looks like those might be 75 or 76 head castings. Yep, those discs come unglued and fall off id the engine gets too hot. So the engine shop can tell if you've overheated the engine for warranty purposes.
That block casting # indicates years 62-80 The head cast # indicates years 72-80 If the engine is original to the vehicle, I'd say you're safe to assume its all 1972. I have the same block casting # but my heads have #1382546, which indicates 68-74 with oil through push rods, which it has. Your head # also has an astrek that says: with A.I.R. I have no idea what that means.
Your dates are more specific than my information. Can you be more specific on my head casting #1382546? My info just says 68-74. Thanks.
