After this past weekend taking the boat out, my motor was sluggish and ready to stall when I throttled it up to the point it almost stalled. When I got it on the trailer, I noticed it ran like a champ in neutral and revved up fast! When I put it into gear, it didn't want to rev up. Well, I thought it was a lower unit issue, but I couldn't find any smoking gun. I jumped on iBoats forum to try and get some help. What an array of ideas it could be, so I better start testing and striking things from the list.
Broad prognosis #1
Sounds like its dropping a cylinder, or two. Multi-cylinder outboards will rev just fine in neutral with no load on fewer than all cylinders firing. Could be a fouled carburetor, could be the power pack going out, could be a bad coil, could be a blown head gasket, could be the trigger malfunctioning. First steps would be to do a compression check, followed by a spark test, followed by a cylinder drop test.
Broad Prognosis #2
Check the fuel vent for any obstruction and the fuel line for any loose fittings that would allow excess air into the system. It could also be a weak fuel pump. I bought a boat from a guy in Florida that claimed it ran good. Had a 115 hp Johnson on it. He said he didn't have time to launch for a test drive. He stuck a set of cups on it and got it going and sounded just fine. Got it home and launched it and had a really sluggish response to fuel. I pulled carbs and they had recently been gone through. Turns out, it had a bad coil. Boat still ran sluggish when in gear after changing the coil. I ended up ordering a fuel pump for it and that cured it.
I think I'm going to run a compression test first, then probably change the fuel pump as I have an idea that may be the culprit. I'll keep you updated on the progress as the Boma is down even before the season has started. ugh...
Fingers crossed you get away with just the full pump boss, but as we all know that may just be the beginning of the spending x/... lemme know if u need a hand, I'll bring the beers ;)
Posts like this keep me from buying a boat.
Ok, I just did a compression test on all 3 cylinders. 130-130-130... Perfect.
Coils? Hmm, I at least know the motor is solid. Now just time to hunt down the issue.
: Latimeria June 11, 2015, 07:03:45 p
Ok, I just did a compression test on all 3 cylinders. 130-130-130... Perfect.
Coils? Hmm, I at least know the motor is solid. Now just time to hunt down the issue.
That's some major good news there!
Good luck Tom. Hope she feels better soon.
We had an issue last week which was a new one ... couldn't get the boat back in neutral after running to the bait barge. :o Ran back to SI and it fixed itself just outside the entrance - go figure. Was fine the rest of the day ... LOL ... any thoughts on that one?
Our compression has been 130-130-90 for years now LOL ....
Good luck .. ;D
Did you check the nut behind the wheel?
: skrilla June 12, 2015, 10:16:52 p
Did you check the nut behind the wheel?
"throttled it up and almost stalled" ....
LOL ... good one Len ...
: WheresMyBeer June 12, 2015, 11:26:56 p
: skrilla June 12, 2015, 10:16:52 p
Did you check the nut behind the wheel?
"throttled it up and almost stalled" ....
LOL ... good one Len ...
That nut has been stripped for a long time but it keeps hanging on. lol ;D
I think it's the water in the gas cap cup not letting the vent do its thing. Hopefully that cleaning helps. I'll have to give it another shakedown trip to test it out.