Jaymike92
Registered Member
Hey All, I have a 75 Blazer that appears to have the original engine, but how do I know for sure? I see the block number that is 3970010 but all I find for that is date range. Would it have the VIN stamped somewhere?
CK5
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Original engine??
- Thread starter Jaymike92
- Start date
Front of the block, on left side, passenger side. There will be a small machined spot with letters n numbers stamped on it. Can be tough to see sometimes.
Jaymike92
Registered Member
Thanks!
The machined pad will tell if the engine is correct year and chassis line. You might have to remove the Alt and wire brush the pad to see the alpha numeric codes. they are hand stamped.
Will the number on the engine block match the VIN?
I do not believe so. the vin will give a one letter code, 8th digit in sequence, it will correspond to an engine line size an HP.
The block codes will be 2 line of alpha numeric and then you look them up. If your engine has been remachined in it's life time the stamped markings may be missing. I just looked at one of my blocks and can barely see a what's left of 4.
Picture is 1975 national service data repair manual. These are normally only cars. Trucks were different manual
The block codes will be 2 line of alpha numeric and then you look them up. If your engine has been remachined in it's life time the stamped markings may be missing. I just looked at one of my blocks and can barely see a what's left of 4.
Picture is 1975 national service data repair manual. These are normally only cars. Trucks were different manual
Jaymike92
Registered Member
Thanks to everyone that replied. I will definitely check it out. I originally was thinking LS swap but now I think I will do rebuild to keep it original. just add Holley Sniper
You can google "suffix codes" and there is a list floating around with about a billion of them on it that breaks it down as shown above in the manual. Just for a whole lot more vehicles.
Would be cool to find you actually had some super rare block that had been swapped in. So far I've not heard of anyone getting lucky like that.
If the pad is clean, its either been rebuilt (decked) or a crate engine, although I think most crates were stamped too, just wrong code for a specific vehicle.
Would be cool to find you actually had some super rare block that had been swapped in. So far I've not heard of anyone getting lucky like that.
If the pad is clean, its either been rebuilt (decked) or a crate engine, although I think most crates were stamped too, just wrong code for a specific vehicle.
