low compression top cylinder

[Jeremiah74]

After compression test I i started tearing down the engine i cant see any damage to piston or bore the pistons however do wiggle , is this normal or is this a sign of bad rings? havent removed pistons yet have to get a 12 point socket . i guess ill be able to tell more after they are completly out. any advice would be greatly appreciated, thanks

 

[JB]

Re: low compression top cylinder

Tell us something useful, Jere.

Like: What outboard do you have?

What were the compression readings?

What did the head gasket look like?

You may be about to cost yourself a lot of money for nothing.

 

[Rollinunknown]

Re: low compression top cylinder

dang might wanna search for DECARB i did this and picked up 32 psi in both cyls..... Carbon makes the rings stick .


i thought it was bs but i tried it and its TRUE..... night and day dif.

 

[Jeremiah74]

Re: low compression top cylinder

Its a 55el78s outboard. reading 35 on top cylinder 95 on bottom. the head gasket looked worn out and tore to pieces when I removed it. Lot of carbon build up on both pistons. the cylinder has some minor scratches in one spot. Ive stet arted breaking the engine down. do i have to remove the flywheel to get the powerhead off? i recently rebuilt the carbs and fuelpump so that much is done. Im just a little stumped on how to get the powerhead out ive taken everything off except the front of th e powerhead where the leaf valves go. I was told by a boat mechanic that it was junk and needed rebuilding so i figured i would start the task myself. Any help is much appreciated thanks!