1986 115 HP Stumble on acceleration

[cabmkr]

I have a 1986 115 "tower of power" It starts and Idles fine, but I have been having a stumble from just above idle. It seams to do it after a higher speeds fun, then you stop and idle or not for a min (kids getting back on tube or such) then when going to power up it bogs and dies. It can be overcome by careful use of the throttle but you deffinlatly have to play with it to get it to pick up revs. Revs up in neutral, didn't bog when I first took off and warmed up the boat yesterday. (wasnt run for about a month)

I have put on a new plunger and it pumped up hard the first time, but afer we had run the boat, back a few hours later the bulb seamed to not get firm again (feul kept getting pushed back to the tank) Last year the boat accelerated fine but didnt idle the best, this year I put some sea foam in the feul and had to adjust the pilots back a bit after running it, now it idles great, but has devleoped this bog after running. It has a 20 gal on board tank. I would almost think it would be water in the feul but we had quite a bit of full throttle running and would have expected any water to have been picked up by the main not the mid circut.

I am a vintage motorcycle guy and restore my own bikes but I have not dont alot of boat work so I dont know the carb internals on outboards as such

Cheers Chris

 

[Texasmark]

Re: 1986 115 HP Stumble on acceleration

Where did you get your "plunger" (usually referred to as a squeeze bulb). I have heard that after market parts, like maybe Atwood to name one, don't perform as well as a Quicksilver.

I was going to suggest that when it bogs to grab your bulb and squeeze it, noting it's "texture" when you did. If working properly, it will be soft, but not collapsed when running. I'd start with that then move on to a new fuel pump if necessary.

Mark

 

[swordfish25]

Re: 1986 115 HP Stumble on acceleration

Sometimes when you lean up the low speed adjustments on a 2 stroke engine it will lag dowm on acceleration because it is too lean between the low and high speed jets. Try backing the jets out a little and try it. You may have to adjust the idle up a little so it doesn`t stall.