1995 mariner 115hp compression issue

[preston334]

I have a 95 Mariner 115hp that ran out oil. (No, the oil sensor didn't go off.) I cleaned out oil tank and lines, replaced plugs and fuel filter as a precaution. As u can imagine, it ran a little rough so I adjusted carbs to smooth it out. The motor doesn't have a whole lot of interest in going into gear unless it's given a little extra throttle. Further investigation found that I've got 120 compression on cylinders 1, 3, and 4. Cylinder 2 has zero compression. Is this more than likely an engine rebuild? If so, would this engine be worth it? Or should I just scrap it and get another?

 

[racerone]

You can remove the exhaust cover ( about 25 bolts ) and look in to see condition of pistons and rings.------If you can do the work yourself it is rebuildable.---At a big repair shop it will cost a lot of money to do these repairs.----Many shops do not want to do these types of repairs anymore.

 

[preston334]

I'm not a master mechanic, but I don't mind replacing a head gasket in car. I've never attempted to go this deep into an outboard before. I feel like I'm confident enough to do it just unsure if it's worth the time and effort. Is there a ballpark figure of the amount of $$ involved to do this rebuild? I'd be pretty disgusted if I pull off this rebuild and the total cost be a few hundreds bucks shy of a new(er) motor.

 

[racerone]

At this time you do not know what needs to be done.----Tear down and inspection is what needs to be done to make up an estimate.

 

[preston334]

10-4. I'll snatch the exhaust cover off sometime this week and inspect it. I'm a little discouraged as to what I may find tho. It's strange because I get zero compression on the compression test yet with the engine running, I can briefly cover the intake on cylinder 2 and the engine will bog down. Then it'll come back up to norm once the cover is removed. Would it be wrong to assume that there has to be some type of compression there? This is the part that doesn't make a lot of sense. Spark plug was a dark gold with a little bit of carbon built but not as much as I thought. Plugs were viewed after an hour of running in the driveway. I'm trying to exhaust all possibilities before I break into this thing. I know once I start, I won't stop. Haha!