FH680 service manual.
Kawasaki 23HP Twin Overheating
- Thread starter djg james
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Update: I wanted to get my yard cleaned up before the holiday but it's been pushing 100 deg the last few days so I didn't push the mower (and me) and only mowed the main half of my yard yesterday. I'll finish up today. No shutting off occurred. It is surging again even at full throttle, but runs smooth once the PTO is engaged. Doesn't surge all the time though.
I had not done anything new before yesterday. To recap, I've changed oil/filter, air filter, spark plugs, fuel lines/filter, impulse line and cleaned the gunk off the bottom half of the engine.
Next week, I mow the entire yard in one session as I used to do before this problem cropped up. If it shuts down again, I'll pop off the exit line of the fuel pump and then crank it to see if I get a flow. This should rule out the fuel pump and a plugged fuel tank exit nipple. If I get good flow, I'll change the solenoid which I receive and test mow (the whole yard in one session) the following week.
Thanks everyone.
I had not done anything new before yesterday. To recap, I've changed oil/filter, air filter, spark plugs, fuel lines/filter, impulse line and cleaned the gunk off the bottom half of the engine.
Next week, I mow the entire yard in one session as I used to do before this problem cropped up. If it shuts down again, I'll pop off the exit line of the fuel pump and then crank it to see if I get a flow. This should rule out the fuel pump and a plugged fuel tank exit nipple. If I get good flow, I'll change the solenoid which I receive and test mow (the whole yard in one session) the following week.
Thanks everyone.
The surge is from the idle circuit being clogged up in the carb. Clean the carb.
Give it a bath in a heated ultrasonic cleaner with Berryman's B12 Chem Tool and drain that corn squeezed gas out and run it dry when overwintering. You have 'junk in the trunk' issues. Take it apart first before dunking.
Why my lawnmower is diesel powered. No junk in the trunk, ever. No issues with any contaminates. I run a Racor fuel polishing 2 micron filter in front of the injection pump. have them on my diesel farm tractors as well as my diesel pickup truck too. Nice thing about a diesel powered lawnmower is, the diesel engine will last 10 times as long as any gasser.
agree with other comments.
Surging but ok when pto engaged is a partially blocked carb.
Ran into this a few times when working at a JD dealership.
People just put up with it till the carb shat itself then fitted a new carb.
Never had any success trying to clean them.
Didn't have an ultrasonic either.
With what replacment carbs cost for this smaller stuff it's hardly worth messing with. My old man picked up a pos cub cadet mower for cheap. Carb was shot among other things that needed fixed. $50.00 carb off Amazon (twin barrel mikuni knock off) and it runs perfectly again. Even at the $35 hr I charge for the side work I do, I can't r&r + clean it (yes I have an ultrasonic cleaner) for what that carb cost.
Ridgehiker
ArboristSite Lurker
I admire the OP's patience, I would have either had it fixed or sent down the road by now, I cannot stand having things that dont operate properly
He's been a good sport about it. Walking someone through diagnostics via the internet just sucks.
There's several reasons for my obstinance
. 1) I just can't afford a new mower of this class. It's a commercial grade mower. 2) Years ago, the local farm store had reputable (adult) mechanics working there. They were good at fixing anything and I took my chainsaws there. Many years later, I took my saw there and it took for ever to get it back. Plus a bolt hole in the muffler was stripped when I got it back. Didn't know this until the top cover melted and I had to have the bolt hole and the cover replaced at my expense. Won't go there again. It's hard to find a good mechanic in my area. That's why I tried to work on my stuff my self. 3) It's kind of fun, learning new things and solving problems. 4) Lastly, I won't be beat by a D@mn machine .
Had a boss I used to work for at a diesel shop said,Lastly, I won't be beat by a D@mn machine
“Don’t let a hunk of iron out smart you!”
I'm taking the position that this entire thread and issues would be eliminated by a thorough carburetor disassembly and cleaning. It's almost 100% a dirty/ plugged idle / pilot fuel circuit.
Good luck OP, carburetors are not such a horrible thing to work one once you've done a few of em.
Good luck OP, carburetors are not such a horrible thing to work one once you've done a few of em.
You might be right. That's a last resort for me
. If in your opinion, it was just a dirty cab, then why would it run geat for 40 minutes and then die?
I can't say for sure, to be honest, but based on what you've written the carb needs a disassembly and cleaning, I can say with almost total certainty.You might be right. That's a last resort for me
Your engine is running lean (surging), which means it's starving for fuel. This condition creates extra heat, which could be resulting in boiling gas in the carb, vapor lock, or something else that's making it shut down after 40 minutes or so.
You can probably find a video on Youtube of a carb disassembly and cleaning on a similar Kawasaki engine.
You might be right. Thanks
