Do i have a misfire? surging idle? Lean sneeze? video!

[jammer777]

hey guys, maybe im just expecting too much, but take a look at this video, i seem to have a few things going on, HOWEVER, maybe this is as good as it gets with an older outboard and im expecting too much, thats completely possible as well, but i have an idle that seems to dance around (its in the videos) and a bit of a sputter at idle, and i cant seem to get it to stay running below 1000 rpms on idle, i have rebuilt the carbs, new plugs, rechecked gaps, redone fuel lines, new fuel pump seals, etc but i haven't done the timing yet

https://www.youtube.com/watch?v=ZD2tdMxQiPY
https://www.youtube.com/watch?v=HciGfNKXEu8
https://www.youtube.com/watch?v=9YN3hFjw7Zg
https://www.youtube.com/watch?v=gW1Xn-nHxvU

So have a look and tell me what you think, It runs fine when throttling up, but there does seem to be a bit of a miss, but the miss is more noticeable at idle, and surging RPM's as seen with the rpm gauge bouncing, which could be the gauge, but you can hear the engine audibly changing when the needle bounces

So i guess maybe have a look and let me know if im nuts and should just put the cover back on and enjoy the lake!

 

[racerone]

To me the motor sounds awfull.----------Report what you find with a compression test.

 

[jammer777]

but doesn't the lake look really nice?! haha I will when i get out there this weekend, I didnt think it sounded that bad, but this has really been my only outboard

 

[jammer777]

well shoot, ive got for compression
#1 50 PSI
#2 119 PSI
#3 119 PSI
#4 119 PSI

Guess thats a bit of a problem, is that a tear down? sigh, or try a decarb? i guess i may be screwed for the summer, anyone have any good pointers to resources for rebuilding these old 115's?

 

[jakedaawg]

Thats not a decarb reading. You have your workk cut out for you or your check book. Rember that boat thing. BOAT=Break Out Another Thousand!!!

 

[jammer777]

you guys think that might be something less serious like a head gasket? or with that low of compression is that just blown rings? and can a person get away with replacing rings on one cylinder or am i just going to have to tear the whole thing down?

 

[jammer777]

And one more question for you guys, and this is a tough one, but looking for opinions, would you guys run this engine for the rest of the year? even with the low compression on one cylinder? so it runs, and it runs not that bad, ive already pulled tubers and wakeboarders and its been "alright" and im kinda stuck somewhere between whether or not i pull it out of the water for the year and tear it down or run it for the summer and hope for the best,

 

[jakedaawg]

Personally, I would pull the boat, pull the head and have a look. A head gasket is cheap. Running with bad rings could make things go bad to the point that it is not economical to make right.

 

[jammer777]

well as i had some time today i ran some seafom through it to see what would happen using the various methods here where running it through a fuel line and putting some straight into the cylinder head on the piston and letting it sit, haha it acutally dropped the compression by about 20 pounds in the bad cylinder after de gunking it, however the rest of the boat seems to run a but better,

I did squirt a bit of straight two stroke oil straight into the piston chamber and reran the compression test and it took it from the 30lb reading up to about 50 indicating bad rings, but im going to pull the headgasket off early next week just to be sure, sigh