Toro 4260 - Kawasaki FR651V acts like it's running out of fuel

need-for-speed

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  • / Toro 4260 - Kawasaki FR651V acts like it's running out of fuel
2011 model. It starts up and runs fine. After a while, it's starts to sputter and tries to die. It sounds exactly like my generator or pressure washer when I shut them down by running the carburetor dry. That's why I think it's a fuel issue (although you can never rule out ignition). About 2 out of three times, if I stop, disengage the blades, it will recover. About 1 out of 3 times it will die. I set for a minute and restart it. It seems worse when I go over bumps. Thing I have tried so far with no change:

1. replaced the fuel filter. I bought it from the Toro dealer so I feel like it's the right filter. They said it was good for up to 30 HP.
2. replaced the spark plugs and air filter
3. removed and flushed the fuel tank, inspected the fuel ines - all look good - refilled with ethanol free gas and carb cleaner and fuel stabilizer (normally I just run normal pump gas - 10%E)
4. Sprayed into the throttle body and on the outside of the carburetor with choke cleaner
4. jumpered the seat switch

So far, I haven't really wasted money because these are all tune up items on a 9 yr old mower. I may have to resort to parts swapping (fuel pump next) but I know that is not really the best approach.

Do these things have a governor? I know when we use to tinker with the governors on min bikes - they would have the same effect - making the engine stumble......

HELP !!!
 

Scrubcadet10

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  • / Toro 4260 - Kawasaki FR651V acts like it's running out of fuel
It does have a governor, but most likely not the issue..

once it dies will it start right back up, or do you have to wait a few minutes?
 

need-for-speed

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  • / Toro 4260 - Kawasaki FR651V acts like it's running out of fuel
Scrub, sometimes it will start immediately. Other times, 60 sec wait does the trick. It does always turn over. Just now I started it up, turned on the mower and let it run at 90% throttle for 20 minutes, and of course it ran great I did try the “coil check” while hot (Pulling one spark plug wire at a time) and it passed- kept running. I even drove it all around the yard as fast and as bumpy as I could. No issues. It only acts up when I’m in the front yard and the neighbors are watching LOL.
 

bertsmobile1

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  • / Toro 4260 - Kawasaki FR651V acts like it's running out of fuel
Spend a few dollars and buy a pair of red in line spark testers.
Hook them up so you can see the glowing globe ( use zip ties ) then go mow.
When the engiine starts to fail look at the testers.
If the glow then flash and continue to do so till the engine just about stops they you are correct you are having a fuel supply problem.
If they stop flashing well before the engine stops then you have an electrical problem.
Confirm this by checking them when you crank the engine .

Once you have confirmed which system is giving you grief then we can star narrowing down things without having you running around in circles chashing your tail& spending money for nothing.

When I have confirmed a fuel problem I hook up a spare tank plugged directly into the carby.
It is only a 1/2 gallon , pinched off a walk behind but it allows me to progressively move it further back to check the carb, fuel pump, fuel filter & lines.
This has been found to be the quickest way to diagnose your type of random cut out problems.

However if you have not done it since you have owned the mower, a valve lash adjustment will not do any damage, but buy a pair of rocker cover gaskets first because they tend to beak up.
When you replace them put sealing goo on one side and axle on the engine side so they will strip clean in the future.
 

need-for-speed

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  • / Toro 4260 - Kawasaki FR651V acts like it's running out of fuel
Thank you Bert! Will this one work ?

spark tester.JPG
 

need-for-speed

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  • / Toro 4260 - Kawasaki FR651V acts like it's running out of fuel
Just ordered 2 of them
 

bertsmobile1

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  • / Toro 4260 - Kawasaki FR651V acts like it's running out of fuel
Thank you Bert! Will this one work ?

View attachment 53427

Actually no they don't work particularly well because the globe is white and really hard to see outdoors in strong sunlight.
Rotary, Prime Line , Oregon & Stens all do a red globe tester with a lot longer wire so easier to fit.
 

need-for-speed

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  • / Toro 4260 - Kawasaki FR651V acts like it's running out of fuel
Ok. Thanks. I guess thats why you recommended red LOL. I’ll send them back and get red.
 

need-for-speed

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  • / Toro 4260 - Kawasaki FR651V acts like it's running out of fuel
update:
I almost returned the spark plug test lights. Then I thought about how readily Amazon will accept returns (i.e. with no questions asked - more or less). So I went ahead and used them. Even though the bulb is clear, the spark indication is red/orange and it was fairly easy to see in the daylight. I put one on each plug. The ignition worked just fine.

Last week, I damn near didn't get the mowing finished, so I decided to try 3 things at once yesterday. I mowed the entire yard (about 40 minutes) with zero hick ups. The steps taken were:

1. I removed the fuel line again, but this time I blew it out - all the way from the tank (including the in tank pipe/ quill) to the carb. I removed the fuel filter first and blew the line out in sections. I actually blew out the line (upstream of the filter) with my mouth because I wanted to feel any resistance, and I did feel some resistance. It did clear. I should have blown it into a 5 gal bucket to see if I caught anything. I really do think that the slight resistance I felt was just fuel in the line. After that, I blew all the lines out with my air compressor.

2. There is a place on the carb upstream of the throttle body where a vapor return line connects. I put a vacuum cap on it.

3. I removed the fuel cap (in case it wasn't venting properly) and covered with a thin rag and rubber bands.

Again, it performed flawlessly. I plan to mow 2 more times like it is to see if it continues to run as designed. Then undo the 2 things I rigged (one week / mowing at a time) to see if I can narrow down the cause. My money is on the fuel cap not venting...............
 
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