Evinrude 115hp problem.

[d_clinton]

Hi guys,<br /><br />I'm pretty new to all this stuff, but I recently purchased a 14ft ski boat with an 82 Evinrude 115hp V4 on the back.<br /><br />When I purchased the boat the previous owner showed me receipts for the engine rebuild that he claims to have had done about 50 hrs ago. <br /><br />I have taken the boat out a few times and it seems a bit sluggish and slow for a small, light boat with a fairly powerful motor on it. I have been told that this could be because the motor is a bit too heavy for the hull.<br /><br />Anyway, I decided to do a compression test on it a while ago and got 3 cylinders all around 110psi but one at around 80psi. The motor runs fine, no flat spots, doesn't miss, doesn't rattle or knock, starts easily etc. Why would I have low compression in one cyl so soon after a rebuild? <br /><br />When I did the test, the motor was dead cold and hadn't been started and I had the throttle closed, would this give an incorrect reading or is it time for another rebuild?

 

[fast_c_class]

Re: Evinrude 115hp problem.

sounds like you got a bad cylinder. first double check your readings with the engine at operating temp. <br /><br />then if it reads low again, squirt some oil in the cylinder that is suspect and test again. <br /><br />if the reading comes up some, youll know you have a bad ring in that hole.

 

[Solittle]

Re: Evinrude 115hp problem.

We WELCOME you sir.<br /><br />A good runnin 115 on a 14' boat is anything but sluggish.<br /><br />You could have low compression on the one cylinder because the previous owner did not fix the problem causing the rebuild. Did the paperwork show which cylinder was bad? Probably the same one.<br /><br />Your next step is to pull the head on the suspect cylinder and inspect the top of the piston and cylinder walls.<br /><br />By the way I'll bet you check the compression before you buy your next engine.

 

[d_clinton]

Re: Evinrude 115hp problem.

Unfortunately I didn't get to see the boat before the deal was done. My dad checked it all out and handed over the cash, I just picked it up.<br /><br />Paperwork just showed all the parts that were replaced (just about everything!!), machine work and tune up.<br /><br />I think I'll have to pull the head off and have a bit of a look, but it's not sounding good! Hopefully I'll get away with a new set of rings or something.