I'm confused
 

Hey guys,
I know, I'll put this in the tech section in a minute but I'm running out of time trying to find the right head gaskets for my 502's. How do I know what generation of engines I have; Gen IV or Gen V or Gen VI?. I have 10 bolts on my timing cover and 16 head bolts. And no, I can't find any stamping number on the block or heads? Thanks in advance.- Jeff

Gen VI will have a timing cover that is composite, with a indicator molded in the timing cover, the Gen V's will have the metal timing cover and the timing indicator that shows the 0 4 6 8 timing #'s on the indicator. (Looks like a Saw Tooth)

Gen V's will require a specific head gasket for the Gen V heads. Gen V's will not work with Gen IV heads.

The water passages on Gen VI were slightly modified to accommodate a GenIV head.

So the Gen VI gaskets should work on either the GenIV's or VI's.

The only GenIV 502's that were made were done by mercruiser using Bowtie blocks.

If you take a pic of your timing cover I can tell you right away what you have.

Thanks Ron,
I'll get a shot straightaway.
Jeff

Ron, here's a few shots. Thanks, Jeff

go to this web site http://www.mortec.com/location.htm it will tell you where to look for the casting numbers and here http://www.mortec.com/bbc.htm for what they mean.

It's hard to tell from the pic, if you look at the bottom picture of the three, by the balancer there is an indicator coming off the timing cover if its a welded on piece with some numbers on it it's a gen V of its just a pointer that is part of the timing cover it's a gen VI. I did some checking on the casting numbers, the block will be marked under the timing cover as to what generation it is

I don't know if you are doing a complete rebuild orjust the heads so that may not help much.

Looked at the picture again, I would say it's a Gen V. I'm sure some more people will way in with their opinions on it, so I f we all come up with Gen V the odds are that's what it is

thanks Ron,
I'm just putting on a new head gasket. Its a metal timing cover with a v shaped pointer(rusted). it almost looks like its put on the cover with silicone. i really appreciate the fast response as tomorrow is my deadline to fix this boat before our 25th anniversary party. - jeff

Its a IV or a V. If it has a mechanical fuel pump location on the engine block, its a Mark IV. If not its a Gen V.

Here is one of the best rundowns on the different versions of the Chevy Big Block I've found.

Ebay Chevy Big Block Primer

Michael