onan 16 hp twin idles rough

[probe123 2]

Hi all,

   I have bought and used a wheel horse 416-8 tractor to cut grass with.  I have no problems with the cut or the power.  I do have a rough idle , but runs fine when open her up and let her run.

Any ideas ?

Thanks,

 

[520hC-120 136]

Carb clean, make sure it’s a thorough one. That’s my best guess.

[probe123 2]

520hC-120,

        Thanks for the " clean the carb " line.  I thought that might be an issue.  I will have that done.

Thanks again,

probe123

[bellevillerod 834]

I have two of the onan's an 16&18. They are very picky to the carb and idle settings. It took me some back and forth with mine to get it right. You have 3 screws that affect the idle too some point. Plus where the throttle stop screw and governor meet you want a small gap between them. You may also want to check the valve settings. Mine both ran much better after I reset those. good luck love those Onans. 

[pacer 3,159]

I second what bellvill sez --- I'm a recent owner of a 16hp Onan myself and boyoboy have I found how sensitive the carb is!! So indeed a GOOD cleaning is probably needed. You'll want to get a kit on hand first, you will need the caskets. I was disappointed in that I didnt see a kit with the main needle included - it did have the idle needle.