Only runs at low RPM

Fri May 09, 2014 8:43 am

Just took over a ball field and inherited their 154. It ran great the first two mowings and now it will only start at low idle. When I attempt to increase the idle it will die. If I spray starting fluid into the air breather it will rev up to the higher RPM when I move idle up but die as soon as I stop the starting fluid.

I have checked the fuel coming from the tank and all is fine. Am I assuming correct that this is a carb issue? If so, what does everything should be my next step?

Thanks in advance!

Re: Only runs at low RPM

Fri May 09, 2014 1:10 pm

You may have either an IH or a Zenith carb on it. Take out the main jet and clean it. The IH carb also has a filter screen in the inlet that can get clogged up. Here's a link to TM Tractor that shows the IH carb, the Zenith is quite a bit different:


Re: Only runs at low RPM

Sat May 10, 2014 9:01 am

Thanks...just got here and it is a Zenith...

Re: Only runs at low RPM

Sun May 11, 2014 9:20 am

Fuel flow problem.

Re: Only runs at low RPM

Mon May 12, 2014 7:58 am

Aside from carburetor ills, I suggest you check the spark advance centripetal weights under the floor of the distributor (the plate the points are positioned on). One of the coil springs which hold the two weights inward (toward the rotor shaft) came loose on my tractor and really messed-up the high speed ignition performance. After servicing the distributor fully and tuning the spark timing, my machine was fine.

Re: Only runs at low RPM

Thu May 29, 2014 9:38 am

I had a fuel flow problem there was a pebble in my gas valve above the screen in the tank. I blew into the gas hose after I removed the hose when i found no gas flowing. I heard a pop in the gas tank. I got it running in the field after it died. It was dying more and more but it would restart. But the last time it didn't restart. But I later flushed the tank. I guess it was a tractor kidney stone.
On any c60 engine lube your governor shaft it can rust up.