Low compression in one cylinder can I hone it?

[Misfit171]

Traded for a 1986 dt25 Suzuki outboard. Got home did a compression test top cylinder is barely 50 lower is around 80. Top has some decent grooves in the cylinder lower seems fine. Guessing by the thermostat it may have gotten pretty hot. Guess I won't know much till I get a book and tear it down. My real question is what kind of honing I need to do to this cylinder. And if it is difficult to take it all apart? Thanks for any info.

[Solarman]

First off, do you have the head off (grooves in cylinder), my question is, what caused grooves in cylinder? And how long has motor been not running? Polished steel surfaces (crankshaft, bearings, rings, etc.) start to rust after a few years (oiling is only done by running motor).

The cylinders can be bored/ or replaced, at a good machine shop. Finding a replacement sleeve, new piston, rings, and all associated parts for the whole rebuild, may be the big challenge. Along with a serious dollar figure, how much experience working on motors do you have? Is it worth buying the proper manual, and needed parts to rebuild this motor?

The crankshafts for these motors (suzuki) is not repairable by any machine shop I've found, so if bad, that entire assy may have to be replaced.

It is possible to "part" the motor out, once you get into it, if
It gets too involved, costly?

Good luck, post back what you find out.

[Misfit171]

Yes I took the head off. the lower cylinder has some grooves the other one is in decent shape. I'm weighing the options but am interested to take it apart just to try it. Really want to inspect the pistons. I've tore down a few 2stroke dirt bikes and honed the cylinders . Gotta dissect it to see the problem anyway.