"Warm" high idle issue?

[Yachtsman1304]

Greetings all. I have a 1997 Merc 4.3 with Thunderbolt mated to an Alpha 1, Gen II outdrive. The boat is "new" to me and I am just getting used to it.

My question is about the idle. According to the manual the idle is supposed ot be about 650 - 700 RPM. My motor idles about that when it is cold (according to the Faria tach it is about 700 RPM ish). After I run it for a bit the idle seems to stay right about 1000 RPM. As you can imagine, shifting from neutral to that is a bit...concerning.

I have a 30 day warranty on the power package and it is going in tomorrow night to get it checked out.

Any ideas about this??

Thanks and keep up the great work on this forum.

yachtsman1304.

 

[Don S]

Re: "Warm" high idle issue?

The throttle linkage is probably not adjusted properly. When you pull the throttle lever back to neutral, the cable attachment on the carb should be slightly preloaded to idle position.

 

[Yachtsman1304]

Re: "Warm" high idle issue?

Thanks for the response Don.

Why would it act differently when it is warm vs. cold? When it is cold it idles where it should but like clockwork once it is warmed up it idles high.

 

[Don S]

Re: "Warm" high idle issue?

I can't tell you WHY, maybe the cables or linkage in the shifter are worn.
I don't have it in front of me to look at or feel the adjustment. I can just give you things to check.