Bad Boy Kawasaki FR651V Mower Quits after 10 Mins

[Bestplayer]

The engine starts good, runs great for about 10 mins, then seems like lack of gas and will die, if you choke it before it dies,,,will run fine for maybe another five minutes or more, It seems to run longer with blades engaged and sitting,,,over actually in mobile mode.
the following have been replaced, gas replaced with new gas (high octane), fuel filter, hoses, fuel pump, and complete carburetor....same symptoms, it does not have a miss ,
and has good power. If you are doing your test run , (takes two people) one driving, one walking behind mower...when it starts to loose rpms, and before it dies, yank the breather off and hand choke it, it will recover
with good rpm's and run for another 5 to 10 minutes and then does this over and over...
kinda at a loss,,,,,coils heating up ???, it seems odd that there is no miss and both coils would fail at the same time and since choking it , revives it,,not enough time for coils to cool, if that were the case.
it acts and reacts like the gas flow stops or slows and a quick choke of the carburetor revives it...
I also have checked the holes in the heads (they are clear), where the oil flows in and out of the heads..

Help the Ghost and would like anyones thoughts...

 

[Scrubcadet10]

Try loosening the gas cap when it starts to faulter.

 

[7394]

Were the valves just adjusted ?

 

[bertsmobile1]

Classic crud in the fuel tank blocking the outlet symptoms
Verrify by blowing up the fuel line before you start ( cap removed ) then again when it stops.
If it is harder the second time it s because you are pushing a slug of debris back into the tank.
It should then run fine for about the same time before repeating itself.
Double confirm by hooking up an auxillary tank the instant the mower stops.
If it firs up & runs the 2nd tank dry then time to drain your tank and clean it out.
You might even need to run a rod up the outlet spiggot.
You will be astounded at what comes out.

 

[Bestplayer]

Were the valves just adjusted ?

Valves have never been adjusted.

 

[Bestplayer]

Classic crud in the fuel tank blocking the outlet symptoms
Verrify by blowing up the fuel line before you start ( cap removed ) then again when it stops.
If it is harder the second time it s because you are pushing a slug of debris back into the tank.
It should then run fine for about the same time before repeating itself.
Double confirm by hooking up an auxillary tank the instant the mower stops.
If it firs up & runs the 2nd tank dry then time to drain your tank and clean it out.
You might even need to run a rod up the outlet spiggot.
You will be astounded at what comes out.

Fuel Tank is clear plastic, been cleaned, nothing there.. will double check the outlet valve

 

[Bestplayer]

Try loosening the gas cap when it starts to faulter.

Have tried it with fuel cap removed

 

[bertsmobile1]

Fuel Tank is clear plastic, been cleaned, nothing there.. will double check the outlet valve

Grass clippings and animal hair become almost transparent when left sitting in petrol for a long time .
However I see the valve lash has never been looked at so it could be closed so far to cause this problem but usually they open up & make it hard to start.
The other quick diagnosis tool is to give the carb a shot of carb cleaner ( try not to use tarting fluid ) the instant it stops.
If the engine fire right up & you can kep it running for a minute or more with repeated SHORT shots of carb cleaner again it points to a fuel supply problem ./
If it makes no difference them youare looking at an ignition problem.

 

[bertsmobile1]

reported

 

[Born2Mow]

Try loosening the gas cap when it starts to falter.

Agreed. Sounds like a classic case of clogged fuel tank breather. The engine runs, the level in the fuel tank drops, which forms a vacuum inside the tank, which starves the engine for fuel.