1988 88spl rebuild

[chopsaw]

Spit a ring out #3 cylinder other day. Pull it down and cylinder wall is scored. Will bore .20 over and hone,polish other three cylinders. New piston and standard rings for other three pistons. Question is, what else should I replace while engine is apart? First time boat motor rebuild but am familiar with auto rebuilds. Any help is appreciated

 

[Dhadley]

Re: 1988 88spl rebuild

Do a search for discussions on rebuilding, theres lots of good info here. Dont order your standard rings until the machine shop measures the other 3. The dial bore gauge will tell you which cylinders need to be bored along with the damaged cylinder.<br /><br />The biggest thing in the rebuilding process is to determine why the damage occured. You dont want a repeat performance. Remember that something caused the ring to break. Thats what you need to correct.<br /><br />Good luck!<br /><br />ps -- make sure you tell the machine shop .020 not .20. Those pistons may be a bit harder to find!

 

[rodbolt]

Re: 1988 88spl rebuild

Hello<br /> just an opinion but the late style pistons from OMC seem to have the ring stop pin moved to the top of the groove. some problems have been noted with this arrangement. I prefer on this application to use the sierra pistons from land and sea or napa. they come complete with rings keepers and wrist pins. it wont cost much more to just rebuild the motor as opposed to a motor patch and the results are much better. bottom main should be replaced anytime the crank is out. the rest are up to you. aqua power sells a complete bearing kit that is reasonably priced. good luck and keep us posted if you do the hone yourself do not use the dingleberry style hone. it will destroy the port chamfer and cause another ring failure.

 

[R.Johnson]

Re: 1988 88spl rebuild

When you have the engine bored, and honed, be sure you have the ports chamfered. Carefully clean, and inspect the carbs.

 

[chopsaw]

Re: 1988 88spl rebuild

Thanks for the reply people. sent the block off today to be bored. THe reason the ring broke was two years ago I blew a head gasket and at that point I didn't have a clue what was wrong with the motor, Just knew it was running awful rough. So I ran it awhile that day fishing here and there (saltwater) then came on home. Well the motor had run hot that day and I think that was when I broke the ring on #3. Did some investigation and found out it was the head gasket blown, had a supposedly reputable marine mechanic replace the head gasket but a month later it was blown again. This time I pulled the head and found out it was warped. Ground the head on top of a pice of thick glass, new gasket and put it back together and it has run alright since then till the other day when it spit the ring out. I've learned alot about boat motors since I started couple of years ago. This forum is a great help!! I get the block back next wednesday so I can put it back together and go grouper fishin! Thanks again for the advice. I would go ahead and completely rebuild this engine but it only has to last me another two years then I can buy me a brand new four stroke.