Idle circuit problem with Holley 4150

AaronWhitt82

Seaman
Joined
Sep 22, 2007
Messages
54
Winterizing the boat over the Weekend I ran into a bit of a problem with the idle circuit......
Boat started up and ran fine, but when she got to operating temp it was idling around 950 rpm's or so. I like to have it idle right around 800 or a little under (when not in gear)
I went to back the idle screw off some and noticed it was backed all the way off and the RPM's did not go down at all. Found this kind of weird.
I did have to adjust the idle a few times this season in both up and down directions and the last time I must have ended up backing it all the way off and didn't notice.
Shut the boat off and turned the air/idle mixture screws in and they were turned out a little over 1 1/2 turns.
I started the boat back up and turned the air/idle screws to 1 turn out and then the idle went down to around 600 and died out.
I turned the idle screw up some and started the boat back up and got the idle to where I wanted it.
I also noticed that when I revved the boat up the RPM's would come back down and stay a bit high (maybe a few hundred) for a few seconds then drop to where I had it adjusted to. (Not sure if this is normal)
Not sure if there is some other problem and if the boat might be too lean now....
Any advice on what else I can do or adjust?
Thanks
 

a70eliminator

Captain
Joined
Sep 9, 2007
Messages
3,762
Re: Idle circuit problem with Holley 4150

Final adjustments need to done with the exhaust underwater. The throttle not returning to the idle stop is adjustable at the cable.
 

zbnutcase

Commander
Joined
Sep 19, 2009
Messages
2,055
Re: Idle circuit problem with Holley 4150

I agree sounds like cable adjustment, see it all the time. 'nutcase
 

AaronWhitt82

Seaman
Joined
Sep 22, 2007
Messages
54
Re: Idle circuit problem with Holley 4150

As in cable adjustment I assume you are referring to the throttle cable?
I imagine that it would need to be tightened up some?
I will check and see if there is any type of slack in it.

I guess I will have to wait until next season then to adjust the carb while on the water.... I think I just have the air/idle mixture screws a bit out of adjustment.

Thanks guys
 

Maclin

Admiral
Joined
May 27, 2007
Messages
6,761
Re: Idle circuit problem with Holley 4150

The cable may be pulling on the throttle some. Usually the cable end goes thru the throttle lever and has a nut on the end that pulls the throttle lever, there needs to be some travel before it begins to move the throttle and that adjustment could be off.
 
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