Kohler Courage SV591 surging and backfiring
#1
Member
Thread Starter
Kohler Courage SV591 surging and backfiring
It is on a cub cadet LTX1040. 19.0 HP Starts fine then surges and backfires. Removed carb and placed it in ultrasonic cleaneer through four cycles then blew it out with air. Still doing the same thing. If I hold choke closed some, it will flatten out. Suggestions please before I buy a new carb. Also drained gas and filed with fresh,
#2
Group Moderator
Did you disassemble the carb and clean out the jets and passages in the carb or did you just plop the whole (assembled) carb in the cleaner?
#3
Sounds like it just hasn't come clean yet. Maybe try some stronger cleaner, purple stuff or maybe stronger.
#4
Member
Thread Starter
Pilot Dane - I disassembled carb except for the brass fitting on the side of the main tube. I tried to unscrew it however it would not move and I did not want to destroy the brass. I poked a wire through every passage I could see. I did not see a way to remove the emulsion tube. Does it come out ??
#5
Member
Thread Starter
Cheese - do you mean "purple power" ?? I used simple green in the ultrasonic cleaner. I thought maybe a sheared key however I can get it to flattten out if I hold the choke closed some. I saw a new carb on ebay for about 16 bucks. Maybe that is a better solution. I hate these Kohler Courage single cylinder engines. They are really not well made.
#6
Group Moderator
I might consider a sheared key on a push mower where hitting something with the blade can stop the engine instantly but on a riding mower it's much harder to do.
I have had carburetors that were real buggers to clean. Some deposits like varnish can be broken down by solvents but if it's a piece of sand or metal than solvent won't touch it and physically removing the obstruction is the only way. If you found a carb for $16 I would be tempted to give it a try though I have gotten some Chinese clone carbs the were real turds.
I have had carburetors that were real buggers to clean. Some deposits like varnish can be broken down by solvents but if it's a piece of sand or metal than solvent won't touch it and physically removing the obstruction is the only way. If you found a carb for $16 I would be tempted to give it a try though I have gotten some Chinese clone carbs the were real turds.
#7
Member
I would double down on cleaning the OEM and use a Chinese job as a last option. Those things work but they're not the same quality as the original.
#8
Yes, Purple Power. These engines do occasionally partially shear a flywheel key for no apparent reason. If it's done that, usually the engine has much lower power and a throaty exhaust noise and really poor throttle response. I think it's still a carb issue. Was it dirty when you took it off?
#9
Member
Thread Starter
No it was not really dirty. There was no crap in the bowl. Inside looked clean also. Like I said, it starts fine just surges, stumbles and backfires. Maybe a bad intake gasket ?? Could not work on it today as I had to get our mower serviced for the season.
#10
Member
Thread Starter
OK I replaced the carb with a chinese carb from ebay. Engine starts fine and does not backfire. It does not surge under load however at no load it does. Also as it is surging from low speed to high, it sounds like someone is hitting the engine with a hammer (a knock). Is this normal on a courage. I am concerned that the bolts for the top cover have loosened and are hitting the flywheel. Please hlep as I have spent way too much time on this engine. I may just stop taking in single cylinder courage engines from now on.
#11
Check the engine mounting bolts, usually this sound is caused by those being loose and the engine is moving around, making the bolts hit the sides of the holes in the frame.