1994 Yamaha 175

[jdupree]

I bought an older Aquasport (for the boat itself) with the understanding that the motor did not run well last time out, but ran great prior to that. Previous owner did state that the boat had sat for several years and assumed that the carbs had water in them (which they did). Good thing is I don't have much in the whole rig at all. Figured I would go through motor before attempting to start it since it has been sitting for around 5 years.

Carbs were a mess which I have redone. The initial compression check was good except for the top port cylinder which came in around 30 pounds less than the rest. So I pulled the head expecting to see damage. I don't see any damage or scoring in cylinder?? Cylinder is as smooth as a baby's behind. I put new head gaskets on and it improved about 10 pounds. I did notice on the old head gasket that oil was on the bottom of gasket for that cylinder. Looks like oil was escaping from the cylinder.

Could this possibly be a stuck ring? I was planning to hook a remote tank to it when I start it and load it up with sea foam.

So basically, this cylinder is still about 20 pounds less than the rest? I don't think that is enough to give up on the motor quite yet??

Any thoughts or suggestions would be greatly appreciated. Thanks!

 

[robert graham]

Maybe run some Ringfree through the motor at the 2 ounce/gallon "carbon removal" dosage to help loosen up any stuck rings.....

 

[ClassicAQ]

I was planning to hook a remote tank to it when I start it and load it up with sea foam.
!

I think you've got the right idea. Robert mentioned Ringfree, either one will do. And let's hope that comment won't spark a 20 page thread on which de-carbing agent is better. Ugh.

By the way, what year/model AS did you buy? I've got a '76 170 myself. Dream boat. Good luck with the rebuild.

 

[jdupree]

I think you've got the right idea. Robert mentioned Ringfree, either one will do. And let's hope that comment won't spark a 20 page thread on which de-carbing agent is better. Ugh.

By the way, what year/model AS did you buy? I've got a '76 170 myself. Dream boat. Good luck with the rebuild.

I picked up a 1978 200 CCP to play around with. The deck and transom were replaced about 10 years ago so they are fine. Fuel tank needs to be replaced and wiring needs to be addressed. Other than that, hull is in very good shape to be a 1978.

I also have a 1999 Aquasport 245 Explorer. That is my family and fishing boat!