1987 175HP Evinrude exhaust cover removal??

[goodtimes]

My friend got a 1987 175HP Evinrude with water in the starboard side plugs. I did a compression check and all 6 of them came out around 85psi. So... I would think its the exhaust gaskets. I have read the Seloc manual and it states that i might need some heat on the bolts to get them out. Should I start the engine and let it warm up a little to get the exaust a little warm? Might be easier to get the bolts out this way. Any tips or tricks to get these bolts out without breaking them?

 

[emdsapmgr]

Re: 1987 175HP Evinrude exhaust cover removal??

These head bolts are pretty good size and have fairly low torque. They should come out without much problem, unless this is a saltwater engine. Try going a quarter turn on each to see if they will all loosen. The compression on these engines doesn't run real high anyway-you're only 10 lbs low and that could be the test rpms or gauge variance. If you don't find anything with the head gasket, check the exhaust cover.

 

[goodtimes]

Re: 1987 175HP Evinrude exhaust cover removal??

I'm pretty sure it's the exhaust gasket since the compression was even on all 6 cylinders.

 

[emdsapmgr]

Re: 1987 175HP Evinrude exhaust cover removal??

If you're going into the exhaust covers, check the inner cover for porosity. Sometimes the casting will develop "leaks" and when under high pressure, will force water back into the exhaust and the lower cylinders. Lay the cover flat and put a small amount water on it and check to see if it leaks through the backside. You can also use a bright light to check for porosity. When reinstalling, follow the service manual specs to get the bottom of the cover flat with the bottom of the block. Also, I'd retorque the cover bolts after a few hours use.