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Onan governor problem


MMcCoy

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Definitely check those points. I had a tractor that lost power as it got warm, and other symptoms similar to yours. Re-set the points gap and cleaned a little oil out of the points box. Tractor runs great now.
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I had the exact same problem with my tractor. I second all the replys regarding the ignition system. I fiddled with the carb and governor spring for weeks to no avail. I finally replaced the points but it still didn't run right except at an idle. In desperation I went down to the local auto parts store and bought a generic chevy condenser, 8mf. Made the engine run like new!
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I have a 16.5 hp Onan engine with a Marvel carb on it. The engine runs perfect idleing, but when the PTO is engaged and/or the engine is put under ANY load, the governor flops around and the engine chokes down and sputters. I've taken the carb off, had it cleaned and float adjusted but doesn't help. Reset all linkage according to manual but doesn't help. Someone at a New Holland dealership told me the governor might be controlled by the magneto (currently not charging but otherwise OK), and if so, would throw off the timing of the governor. Thanks for any help, advise, or ideas.
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Hi Matthew, I would also check the points. The problem we have seen is the point box slides develop a crushed area were the bolts hold them down. This allows the point box to slide after you have properly adjusted the timing. If you notice your slots have impressions of the clamp bolt, use some heavy duty washers to increase the diameter of your clamping area. If you have access to a machine shop, have them mill the point box flat. Then install the hd washers, be careful, do not mill off too much, you will not be able to adjust the timing.
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I HAD THE SAME PROBLEM WITH MY POWERMAX. I CLEANED CARB AND ADJUSTED. IT WOULD RUN GREAT AT A IDLE BUT WHEN YOU PUT A LOAD ON, IT WOULD BACK FIRE SPIT AND SPUTTER. I REPLACED AND ADJUSTED POINTS. DID NOT HELP!!! I REPLACED COIL, COPPER CORE SPARK PLUG WIRES(NOT THE HEI WIRES) AND NEW SET OF PLUGS AND IT RUNS GREAT. STARTS BETTER MORE POWER.
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