Not running right at idle speed

[Eye Spy]

I have a 27' sportcraft with a 454 in her. Yesterday, I left the dock and ran 12 miles where I anchored perch fishing. When we headed in, I noticed the boat was not running right when I started out. After giving it some gas, it took off and ran fine all the way in. Once in the channel, I slowed to idle speed and it was running terrible again. It didn't run or sound good at all. I thought it was going to stall out a couple of times but I would take it out of gear and it would run fine again. However, after it was back in gear it was back to running terrible. So it runs fine at idle speed out of gear and also runs fine once I give it gas, but runs terrible at idle speed. Any suggestions?

Ryan

 

[Eye Spy]

Re: Not running right at idle speed

anyone?

 

[superbenk]

Re: Not running right at idle speed

Tune up and timing, maybe? My timing was off a couple degrees and I had the same problems. Timed it properly and it runs nice and smooth at idle.

 

[Bondo]

Re: Not running right at idle speed

Ayuh,.... How long's it been since the ole girl had a Complete Tune up,+ Full Service,...
My 1st Guess would be the idle circuit of the carb is boogered up.... Dyin' under Load..

 

[Eye Spy]

Re: Not running right at idle speed

She gets a complete tune up every spring, new plugs, wires cap etc.

 

[Bondo]

Re: Not running right at idle speed

She gets a complete tune up every spring, new plugs, wires cap etc.

Ayuh,... Then it's probably time to Rebuild the Carb...

 

[jtybt]

Re: Not running right at idle speed

It's probably the low speed air screws that need adjustment.

First of all, NEVER screw the needles down tight. The steel needles seat in pot metal which are very soft and will deform which destroys the ability of the needles to adjust.

Set idle speed to 650 RPM and turn one of the screws to smoothest idle. A vacuum gauge is best. make adjustment slowly to let the new settings take effect.

Re-set idle to 650 and do other side.

 

[BAproject]

Re: Not running right at idle speed

gotta be the carb or timing, do both and see if it works

 

[mthieme]

Re: Not running right at idle speed

Yup, I'm with Bondo. Pop off the flame arrestor and see if she is dripping gas down the venturis.

 

[bigskiohio]

Re: Not running right at idle speed

adjust your idle with cable off. might take a couple of tries, keep slight pressure on throttle arm at idle.