Model a head on model b engine

Don't forget to plug the "steam" holes.

I have had an A head on a B engine for over a decade without plugging those holes. I was told I should but couldn't see the point. Maybe I did the wrong thing but it has been fine. What reasons were given to you? (Not being confrontational)
 
I have had an A head on a B engine for over a decade without plugging those holes. I was told I should but couldn't see the point. Maybe I did the wrong thing but it has been fine. What reasons were given to you? (Not being confrontational)

I think its a matter of the "distance" between the hole and the nearest "free edge" of the gasket. Everywhere else around the head the distance is "standard" and (should but commonly doesn't) have the "bound edge" of the copper cover to add to the gasket compression.

The "commonly doesn't" would be the "aftermarket" modern gaskets. For many high compression heads these are the recommended gaskets.

I tend to agree though. Not necessary to plug the holes if you use a quality gasket.

The literature for the original Gordon-Smith compressor heads - based on a Model B head at least the part on cylinders 1 and 4 - don't mention the holes or their plugging. But that is a "different" and perhaps even more challenging application.


Joe K
 
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Agree with posts 5 &7. Had a couple in my shop that leaked using Best Copper gaskets. Plugging the holes stopped the leaks. Agree, it is not necessary to plug the holes unless the gasket leaks. (Smile)
 
This slide should help:
 

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If you use an A head gasket with a B head or block it may not adequately cover the holes.

The 4 holes down the center-line of the block re the ones that should be plugged. They need to be plugged flush with the block surface to support the gasket.
 
High compression Model A head allows modern, “leakless” A water pump that is cheaper and easier to get than reworking or buying a B motor pump. Not a huge difference but keeping the B head does add that factor. Just went through it….-Chris in Boulder
 

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i have some B heads if you want one also B water pumps


Do you still have this available? I just removed my head due to some overheating issues to find my block filled with stop leak from a precious owner. Would like to upgrade while I'm at this stage and looking to assemble asap.

Please let me know.

Thank you in advance.
 
Do you still have this available? I just removed my head due to some overheating issues to find my block filled with stop leak from a precious owner. Would like to upgrade while I'm at this stage and looking to assemble asap.

Please let me know.

Thank you in advance.

If you can't get one from the previous poster, I have several non-restored B heads I'd like to get rid of.

I have a diamond B block and plan on replacing the B head with an A head for looks, sometime in September. All of my B water pumps are spoken for (most are already on their way to Australia) but I will also clear out my stash of B heads as well.
 
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