'85 Evinrude Compression #4

[Chester797]

I just completed a rebuild on my 85 115hp rude and the compression read 120psi all around. Was very happy, timmed it and put it in the water. When I went to ease up on plane I noticed that the engine acted like it had no power. As I backed off I found that the engine was not idling smooth. I loaded up and headed home. Next morning I checked the Compession 120psi in all except #4 which read 90psi. I thought I popped a ring, but when I removed the head, that cylinder was milky, like water was in there. After reseating the head gasket I was able to get back to 110 psi, but then suddenly back to 90 psi. Any suggestions on some way to seal the cylinder? Or could I be leaking somewhere else? Its a V4 XFlow.

 

[NDSSS]

Re: '85 Evinrude Compression #4

Hi<br />Did you retorque the headbolts after it was warm?<br /> If I remember correctly the Headgasket has a sealant on it so to seal the improfections of the <br />casing. So once it comes off the block I would trash it.<br /> When I worked on OMC products, I would replace the headgasket when-ever the head came off, kind of a insurance policy on my part. <br /> I would install a new headgasket, warm it up,<br />Retorque the headbolts, and then check compression.

 

[rodbolt]

Re: '85 Evinrude Compression #4

hello<br /> did you surface the heads? you can remove the intake transfer port cover to verify the rings. if you use a small blunt pick and push them in they will spring back if not broken. if you did not clean the heads or the gasket at the filler block is leaking then water may get in. I always surface the heads anytime they are removed and I coat both sides of the head gasket with OMC gasket sealing compound<br /> good luck and keep posting

 

[Dhadley]

Re: '85 Evinrude Compression #4

If you are sure the head gasket is sealing and you still cant find where the water is coming from, get the powerhead pressure checked. That will pinpoint the leak. <br /><br />We've seen cracks in the exhaust area and that lets water get in a particular cylinder. For some reason it generally number 4. <br /><br />Why did it have to be rebuilt to start with?