Yanmar 2GM20F Engine will not go back to idle

[Gardnera]

I own a 1999 Hunter 310 with a Yanmar 2GM20F diesel. Last night after the Wednesday evening club race I was motoring back to my slip and I noticed that the RPM was above 1,000 even when I had it in idle/neutral. I went back to the boat and ran the engine, it powers up ok but whenI go back to neutral it only goes to about 1,000 RPM. I looked at the throttle linkage at the motor, sprayed some WD-30 but it does not go back to idle. I can manually put it in idle at the engine but not at the helm. I feel like the problem may be at the helm control vs an engine issue. Any suggestions?

Alan
BayGypsy

 

[woodster]

check your throttle cable for slack and be sure it is secure in the mounting brackets..also check the throttle stop screw for idle adjustment

 

[Stu Jackson]

In some cases (pi!) they are BOTH --- there are threads in the alternator tab and some skippers have chosen to install longer bolts with nuts. Only YOU can tell by backing it out and seeing what's there.

 

[woodster]

In some cases (pi!) they are BOTH --- there are threads in the alternator tab and some skippers have chosen to install longer bolts with nuts. Only YOU can tell by backing it out and seeing what's there.

i think the above answer belongs to another thread

 

[markwbird]

I have had this issue with my 3gmF. It was the spring loaded mechanism that the throttle cable attaches on the engine. A raw water leak above created corrosion on the linkage and it got sticky. I fixed the leak, power washed and dried the engine including the linkage and oiled the linkage with light machine oil. Works better than ever now. The point of this story is that it could be many things but, most likely, it's a sticky linkage. You just have to investigate.

 

[Gardnera]

Thanks for the suggestions, I will investigate closer and report back what I find.
Alan