Case Colt Ingersoll Tractors banner

Case 444 running terrible

429 Views 6 Replies 6 Participants Last post by  myerslawnandgarden
My trusted helper of 45 years is giving me fits. Last winter with the snow blower on it wouldn't rev to full throttle and stay there as the lever kept slipping back and some backfiring noted. I replace the entire throttle cable and lever with new. Now with the the mower attached it's worse. Barely reachs 2500rpm without backfiring and really running rough. Starts right up and idles good. Replaced fuel filter, removed and cleaned the carb (Walbro one adjustable jet) and reset point gap. Even tried a .001 each way looking for a bit of timing change. If run with the AC cover off it blows a lot of raw fuel out past the choke valve. I've tried different governor settings also.
I think I'm hearing some ignition ping but exhaust noise makes it hard to define.
I run "rec" gas almost exclusively.
All suggestions appreciated.
1 - 7 of 7 Posts
I might suggest that you consider the condenser as a possible cause. Typically, the engine will start easily and idle well, but any attempt to increase the throttle position does not go well. If you were to run the engine with the breaker point cover removed in a dimly lit area, you would notice considerable arcing at the points. Blue spark like an arc welder.

Bob
  • Like
Reactions: 4
I run "rec" gas almost exclusively.
All suggestions appreciated.
Not sure what you mean by that statement.. If you are not running "non-ethanol gas especially during the winter season" that should be a starting point. I agree with Bob though that it seems more electrical than fuel based. To even try to answer your question though you need to provide a LOT more info. First the throttle lever - if that moves at all after being set then yes there is obviously a throttle assembly problem. What you are describing after that though sounds more fuel related though. To answer your questions I think you will need to tell us more of you issues.. Start by even telling us what we are looking at ? What engine, age, service, etc.. be specific please.
Agree with Bob, the condenser is cheap and easy to rule out and can make them act all kinds of ways. When was the last time the valves were adjusted? And last time the head pulled, decarboned, inspected? If you slowly apply some choke does it get better or worse?
  • Like
Reactions: 2
I Agree with Rockland valley. And could just be a bad ground on the condenser. Or a sticking plunger that moves the points.

Noel
  • Like
Reactions: 1
Agree with condenser needs to be subbed. I usually just disconnect the condenser in the points box and install the condenser at the NEGATIVE post on the coil. (more user friendly.
You say you see a backwards spraying of gas mist at the carb choke.
If condenser don't make it go, I would compare the compression on each cylinder but I would GROUND OUT the spark plug wires one at a time and compare the power loss. When I say ground each one I slide the spark plug boots back and ground with a screwdriver. Why ground the plug wire you ask: Because the onan uses a waste spark ignition and pulling a plug wire off wipes out both cylinders. One bad plug wire or a bad spark plug will also upset the apple cart, so check the minor things first.
  • Like
Reactions: 1
Agree with condenser needs to be subbed. I usually just disconnect the condenser in the points box and install the condenser at the NEGATIVE post on the coil. (more user friendly.
You say you see a backwards spraying of gas mist at the carb choke.
If condenser don't make it go, I would compare the compression on each cylinder but I would GROUND OUT the spark plug wires one at a time and compare the power loss. When I say ground each one I slide the spark plug boots back and ground with a screwdriver. Why ground the plug wire you ask: Because the onan uses a waste spark ignition and pulling a plug wire off wipes out both cylinders. One bad plug wire or a bad spark plug will also upset the apple cart, so check the minor things first.
This is a 444 tractor which is powered by a Kohler K321AS engine, so no condenser in the point box and no need to ground any plug wires.

Bob
  • Like
Reactions: 3
1 - 7 of 7 Posts
Top