boat doesn start properly after tubing>?

[findinghomer]

had boat out this weekend, ran great after plug, diaphram, needle, change and a decarb. however after tubing for a little bit, when we come to a stop to pick up a tuber, the boat wont idle. it will start then shut right off. in order to keep it going i have to put it into high neutral, then cram it into gear. once its running it stays running, but it wont idle after running around tubing. is my float bowl flooding at high rpm? bc once i get back to regular cruising, its all good. what should i look for? thanx for any feedback.

 

[tavett]

Re: boat doesn start properly after tubing>?

My Force 125 did the same thing last summer, and I put a can of Sea Foam in it and it's ran fine since, but I keep an extra can nearby

 

[findinghomer]

Re: boat doesn start properly after tubing>?

My Force 125 did the same thing last summer, and I put a can of Sea Foam in it and it's ran fine since, but I keep an extra can nearby

yea did that, ran a 16oz can and about a half a gallon of gas through it, . i even took plugs out and sprayed deep creep into each cylinder. its always done this, and i was hopin the tune up will eliminate it. it did allow me to idle , and operate when cruising , its just after running WOT (or close to it) at heavy loads that it does this.

 

[Frank Acampora]

Re: boat doesn start properly after tubing>?

What you are experiencing is similar to a vapor-lock. When you run at high load settings, the engine runs hotter and since the carbs are not isolated from the block, fuel simply boils out. You can try removing the thermostat or substituting a colder thermostat--don't ask me which, I have never changed one. Putting the engine in fast idle position and letting it run for a couple of seconds or longer might help too. You can also try raising the idle speed a bit but then there is the drawback of a slightly too high idle speed under regular operating conditions. You can also try having someone squeeze the primer bulb before you restart, but quite frankly, I have had the same problem on my 140 and never tried this. I simply live with it.

SO: Ultimately you must figure a way to keep the engine cooler under high load conditions.

 

[roscoe]

Re: boat doesn start properly after tubing>?

What are your wot rpm when cruising?

What are your wot rpm while boarding?

Are you actually boarding at wot?

What do you have for a boat and motor?

Prop pitch?

 

[findinghomer]

Re: boat doesn start properly after tubing>?

What are your wot rpm when cruising?

What are your wot rpm while boarding?

Are you actually boarding at wot?

What do you have for a boat and motor?

Prop pitch?

i cruise about 3,000 rpm. average when boarding 4800, WOT 5500. boat is a 20ft maxum cuddy with 125 hp outboard motor 15 in prop.


and frank thanx for your input, i am kind of just dealing with it, but since i got my boat running really good now, guess im gettin picky and want it to run perfect

if it is what it is thats fine, its no big deal. i mean i CAN get it running after tubing, i just wanted to figure out wth is goin on and if i can remedy it. raising idle speed could be ideal, as it is now, it idles very low in neutral about 500-600 rpm. but i dont know how to adjust that, my carb only has air mixture adjustment screws

 

[roscoe]

Re: boat doesn start properly after tubing>?

Idle speed should be 800-1000 in neutral,
600-800 in gear, so it looks like it could go up some.

There is an adjustment screw on the throttle tower shaft, it adjusts the throttle setting on both carbs. The screw is on the cam where the throttle cable attaches to the throttle tower.

 

[findinghomer]

Re: boat doesn start properly after tubing>?

thanx roscoe im goin to look for that, i been diggin to see how to adjust that always come up empty. i have a manual but it does tell you how to raise idle speed. only how to adjust mixture screws.