Motor is "hunting"

[ketron47]

RPM varies greatly while running without a load. Once mower is engaged it runs smoothly. Thanks for any info.

96 MTD: Model 1465828P352
20 HP Onan: Model P220V-I-11437G

 

[reynoldston]

The low speed jets in the carburetor are ether dirty or out of adjustment. Try ajustment frist

 

[ketron47]

The low speed jets in the carburetor are ether dirty or out of adjustment. Try ajustment frist

These carbs are non adjustable; except for changing the jet. If dirt is the problem; wouldn't it be evident at all times (load/no load)? Thanks for the reply.

 

[reynoldston]

I am just going by what I have ran across in my years of repair. I don't know what you have for a carburetor but I have found when a engine hunts under no load condition that it turns out to be a low speed jet problem in the carburetor.. Like I said dirt or whatever. They run good under a full load. Now what you or someone else have come across I don't know??

 

[Rivets]

Reynoldston is spot on, check for dirt or corrosion in the idle jet. You could try running a good cleaner through the entire fuel system, but will probably still either remove and clea or replace the idle jet. Dirt in carbs is not always seen or evident at all times.

 

[EngineMan]

Hunting is almost always caused by a lean fuel ratio (partially clogged or mis-adjusted carburetor or air leak)