1970 4hp Evinrude

[newfiez]

Hey,

I have a 1970 4hp Evinrude 4036EC that has 82 psi top, 57 psi lower. I was going to put a new head gasket in to give it a try, and I noticed a small crack in the lower cylinder outside wall (see pic below). I'm not sure if this will make a difference for compression seeing how it's on the outside.

I understand with a new head gasket I put it in dry (I've never changed a head gasket that has no metal crush gaskets in them)?

I may be at a loss with this engine, it looks like the last guy made his own gasket and used silicone to seal it. The head bolts holes have heli-coils installed, the cylinder head is slightly warped and it looks like it has welds to repair the spark plug holes!

 

[Daviet]

Re: 1970 4hp Evinrude

I don't think you have much to lose by installing a head gasket and see how it runs.

 

[nwcove]

Re: 1970 4hp Evinrude

buy the head gasket, straighten up the head by sanding it on a piece of glass, and see if the comp numbers come up.

 

[freddyray21]

Re: 1970 4hp Evinrude

I would clean up the block as well and use some of this on the gasket. http://www.rockymountainatvmc.com/p...ype&prodFamilyId=31927&stockId=810471&ref=gmc

 

[newfiez]

Re: 1970 4hp Evinrude

I've used the copper spray on my steel head gaskets on my car, I have some left so I'll give it a try. I have a new problem now though, one of the middle head bolt holes were stripped, and they used silicone to hold the bolt in place. Now I have to heli-coil or use a larger bolt

 

[Daviet]

Re: 1970 4hp Evinrude

I would use a heli-coil.