Sticky Throttle?

[Trojan32]

I have twin inboard engines with dual controls (flybridge & cabin). One of my engines will intermittently idle high. Under power will idle at 1200 rpm, but will shoot up to 2500 when out of gear. I shut the engine down a couple of times and restarted and the engine idles okay. But others times it jumps back up to 2500. I did have a linkage problem between the upper and lower throttles, but that has been fixed. I've sprayed the linkage down with lubricant too. Any thoughts?

 

[NYBo]

Re: Sticky Throttle?

Have you verified that the throttle is returning to the idle stop?

A vacuum leak can also cause high idling.

 

[Trojan32]

Re: Sticky Throttle?

Yes, it appears to be returning okay.

 

[Trojan32]

Re: Sticky Throttle?

It's my weekend boat... I haven't had an opportunity to check it after acts up. Unfortunatley, I've had a boatful when it happens then bring it to the dock on one engine and return to entertaining my crowd. It seems to happen after I have been running her at 2500 to 3000 rpm for 10+ minutes.