Sporatic Hesitation and Stalling

[Will Fish]

As the title states, I am experiencing a sporadic hesitation when running. The Boat is a 21' cuddy cabin with a fresh rebuilt GM 250 inline 6 (30 hours). The hesitation is not consistant, and sporatic. It is a faint hesitation and barely changes the rpm. It also does not matter what speed I am running at. I've noticed it does not occur until the motor is fully warmed up and I am running for at least 20 min (time it takes to get out of "no wake" zone and running at a higher rpm for a few minutes). Oil pressure is good bet 40-60, and temp is 160-175. When I pull back on the throttle to an idle when the hesitation occurs, she will stall and take about 10-15 min to start again. I'm thinking a fuel problem and possible water in the fuel. I'm going to drop the water separator and see what I'm working with, also check the small filter in the Carb. Any other ideas what I should check?

This problem just occured this past weekend and has been running great since install. She stalled twice on me, and did nto happen the entire time I was out. When it was not happening the motor ran great and sounded real strong.

 

[Bondo]

Re: Sporatic Hesitation and Stalling

As the title states, I am experiencing a sporadic hesitation when running. The Boat is a 21' cuddy cabin with a fresh rebuilt GM 250 inline 6 (30 hours). The hesitation is not consistant, and sporatic. It is a faint hesitation and barely changes the rpm. It also does not matter what speed I am running at. I've noticed it does not occur until the motor is fully warmed up and I am running for at least 20 min (time it takes to get out of "no wake" zone and running at a higher rpm for a few minutes). Oil pressure is good bet 40-60, and temp is 160-175. When I pull back on the throttle to an idle when the hesitation occurs, she will stall and take about 10-15 min to start again. I'm thinking a fuel problem and possible water in the fuel. I'm going to drop the water separator and see what I'm working with, also check the small filter in the Carb. Any other ideas what I should check?

This problem just occured this past weekend and has been running great since install. She stalled twice on me, and did nto happen the entire time I was out. When it was not happening the motor ran great and sounded real strong.

Ayuh,... I think yer headed the right way,... It starts doin' it, After the choke pulls off, so the carb is where I'd head too,...

 

[Will Fish]

Re: Sporatic Hesitation and Stalling

Ayuh,... I think yer headed the right way,... It starts doin' it, After the choke pulls off, so the carb is where I'd head too,...

So I finally have been able to get into this. Pulled the filter and had some sediment in it so it was changed. Also pulled the carb. Had no reaction to 1 of the air/fuel adjustments. So I had the carb rebuilt. The guy told me part of the linkage was bent, had a bent piston in the carb, choke was worn out, and I had to be sucking air cause 2 gaskets were torn. Put the fresh rebuilt in and after a few carb and choke adjustments she's purring.

Took a quick test run at all different speeds with no hesitation at all!!!!

I am still having a problem getting back to idle. Thi ls has been a problem for years that I just can't figure out. If I rev up or am running, when I pull back to idle speed, I'm running at about 1500-1800rpms. Wayyy too fast. I have to goose the throttle a few times and she will eventually come back. Any thoughts? Only thing I can think of is a linkage issue or controls. I replaced the throttle cable this year which didn't change the problem.

 

[Bondo]

Re: Sporatic Hesitation and Stalling

So I finally have been able to get into this. Pulled the filter and had some sediment in it so it was changed. Also pulled the carb. Had no reaction to 1 of the air/fuel adjustments. So I had the carb rebuilt. The guy told me part of the linkage was bent, had a bent piston in the carb, choke was worn out, and I had to be sucking air cause 2 gaskets were torn. Put the fresh rebuilt in and after a few carb and choke adjustments she's purring.

Took a quick test run at all different speeds with no hesitation at all!!!!

I am still having a problem getting back to idle. Thi ls has been a problem for years that I just can't figure out. If I rev up or am running, when I pull back to idle speed, I'm running at about 1500-1800rpms. Wayyy too fast. I have to goose the throttle a few times and she will eventually come back. Any thoughts? Only thing I can think of is a linkage issue or controls. I replaced the throttle cable this year which didn't change the problem.

Ayuh,... the throttle Cable has to hold the linkage snug against the idle adjustment screw on the carb,...

I'm guessin' yer's don't,...