MAX IV Kohler Magnum 20hp won't idle low

[machinistbcb]

Hi,

I have been fixing up a Max IV that I picked up a few months ago. I am having trouble getting the engine to idle and low speed. I have tried adjusting the carberator as specified in the manual but the engine will cut out when I try to turn the idle down. The engine and carb runs fine at a higher idle speed, but the high idle engages the clutch to soon. I have changed the plugs, oil, and air filter, but have not taken the carb apart yet. Should I go ahead and take the carb apart and give it a good cleaning ?

Any ideas as to what to do ?

Thanks,

Brian

[racerone3]

I would tear the carb down. sounds like trash in the low speed circuit (a pretty common problem on a briggs) A blockage there will keep it from getting fuel when the throttle plate is closed. Take it apart and blow out all passages. you can also run a small wire through them. If there is a lot of varnish from old fuel, carb cleaner or acetone will remove it.

[Obsessed]

You might also want to check that its not an incorrect belt...some aftermarket belts can be slighty different sized and can increase belt drag on the primary clutch thats spinning on the motor making it difficult to spin at low rpm's. A mis aligned engine and trans can have a center to center that is to far apart and can give the same result....some newer secondary (or driven) clutches are very easy to adjust for proper belt tension by adjusting the distance between the two sheeves