Compression problems with my 'rude 115

[SmokeInTheWater]

I'm having trouble with my 1996 Evinrude 115hp (E115TLEDA). Engine seems to run fine while running with muffs on in my driveway but when in the water running under a load it lacks power and wants to stall. I checked compression and was not pleased to find out that two of the cylinders were low. 1= 90, 2= 120, 3= 30, 4=120. Any chance this could be caused by something other then a blown gasket and/or rings? Any help or suggestions would be of great assistance.

 

[Dennisanoka]

Re: Compression problems with my 'rude 115

Besides those two possibilities the cylinder maybe scored. 90 on 1 is also lower than you want given what 2 and 4 are.

 

[R.Johnson]

Re: Compression problems with my 'rude 115

Pull the cylinder head on that right bank.

 

[SmokeInTheWater]

Re: Compression problems with my 'rude 115

It's not pretty under there........... The 3 piston is shot and it looks like the 1 is not far behind. Looks like maybe one of the rings blew and damaged the piston. Not what I was hoping to find. Needless to say a job this size is a bit out of my league so any suggestions on what I should do would be great.

 

[chbailey]

Re: Compression problems with my 'rude 115

Ouch! If only the piston is damaged you might be halfway ok. You'll have to tear down the motor and check the cylinder walls for damage. It's probably there. Your looking at boring the cylinder holes out and putting in larger pistons. I'm not an expert on this but I'm pretty sure you have to do this to all cylinders or the compression rates are off. (I'll defer to the guys who have been around longer on this one.)

The bright side is that you'll have more HP in the end. Not sure if it's worth the hassle or $$$ though.

 

[emdsapmgr]

Re: Compression problems with my 'rude 115

You can bore just one or two holes and be just fine, if you use genuine Bombardier replacement pistons. The increased displacement is negligible. All oversize pistons weigh the same as the standard bore, so there are no balance issues. Having said that, we don't follow that practice- we bore all four, since there is bore and piston wear on the remaining holes. It just depends on what your long-term expectations are for the engine when it is back together.

 

[Dennisanoka]

Re: Compression problems with my 'rude 115

Sounds like you must bore at least one. Maybe you can hone the other 3 and just replace the rings in those 3. Personally if I didn't need to bore a cylinder, I wouldn't only because it may prevent a future re-build on that cylinder, but everyone has their own beliefs.