Head gasket variations in 172 engines

Does anyone know the difference in thickness between the head gaskets of a 172" gas versus diesel engine? The parts book shows them as being different, so if we assume the block is the same dimensionally between the two, that about has to leave the thickness as the only difference.

The reason I ask is because I'm putting my 6000 engine together right now, which is essentially a 6-cylinder version of the 172 four banger. Since NH does not sell a gasket kit for my engine, I ordered a complete gasket kit from an aftermarket supplier, which included a head gasket. I also ordered a head gasket from NH because something didn't look right about the aftermarket version. To my surprise, the head gasket in the aftermarket kit was twice as thick as the OEM gasket, .080" versus .040".

Of course, the service manual doesn't make a distinction between gas and diesel head gaskets, however the parts book shows them as being different, just as with the 172 engines. This is why I'm curious as to whether or not someone knows for sure of the differences between the gas and diesel head gaskets on the more common 4-cylinder models.

I went ahead and put the thin gasket in my engine, since it was the OEM replacement from NH, made by Detroit Gasket. I shudder to think about how hard starting this engine would have been in the cold weather had I not caught that.

Wow.

I wish that I could help you, Bern, but you are working in an obscure area.

FWIW: I would have done as you have done. CR is a good thing, especially in a diesel engine.

It's the world that we now live in.

Good luck with your 6000 restoration, and let us know how it performs once completed.

Dean

I think I would question that thick of a head gasket on any engine!!

A 172 diesel has more head bolts than a 172 gas is one reason for a different part number. I don?t know the thickness of both. I might have an old one of each somewhere. I?ll try to find them and measure both