Head Gasket vs. Low Compression HG

[bennysku]

I noticed low compression in piston #1. Pull the head off and found the Head Gasket was blown out on the bottom. (After finding whomever I bought the boat from switched igintion coil #3 w/ #1 - oops) Anyway I was going to purchase one from iboats but they have two head gaskets listed for a '77 envinrude 140hp. The head gasket (18-2956) for $10 and a low compression head gasket (18-3898) for $23.

What's the difference?

 

[bennysku]

Re: Head Gasket vs. Low Compression HG

The second part number was supposed to be 18-3898

 

[JUSTINTIME]

Re: Head Gasket vs. Low Compression HG

email them and ask
i think one id for if u deck Ur heads, u need to lower Ur compression

the thicker the gasket the lower the compression

 

[tashasdaddy]

Re: Head Gasket vs. Low Compression HG

brp list the original number as 0318358