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I have a 2001 25 hp Kawasaki engine on a bobcat mower. It runs great when the blades are not engauged but when i engauge the blades it runs great for 30 minutes then it dies. It restarts and I run it for a few second then dies. It just keeps dieing, it seems to me like it's not getting fuel...I check the tank cap it's open, the fuel filter is new, I check the fuel pump and it's has a good stream . The only thing I can figure its the carburetor. Ive even tried seafoam and nothing it still does it. Any suggestion ?

We have this problem come into the shop with older bob cats. How many hours are on the unit? It may be time for the heads to be replaced or the valves to be lapped.

Edwards Saw Service in Glen Mills PA

The mower has over 2000 hours but the engine has less than 200 hour.

I'm sure you already know this but an engine needs the right amount of air, the right amount of fuel, compression and spark at the right time to operate properly. If one of the above factors are missing or in the wrong proportion the engine will not run or may run poorly. When the symptom is present find out which one(s) is/are missing from the equation.

It doesn't take much to get an engine to run erratically. One would think that less than 30 minutes would be enough to cause an intake valve with insufficient gap to heat up enough to come off its seat. Wouldn't hurt to go through the carburetor and give a good cleaning with carburetor cleaner and re-assemble. Enrichen the mixture screw some couldn't hurt. Too much and it would blow black smoke~~~ I'd take the valve cover off and look at the gaps and see what they are set at.

HBA said:

I have a 2001 25 hp Kawasaki engine on a bobcat mower. It runs great when the blades are not engauged but when i engauge the blades it runs great for 30 minutes then it dies. It restarts and I run it for a few second then dies. It just keeps dieing, it seems to me like it's not getting fuel...I check the tank cap it's open, the fuel filter is new, I check the fuel pump and it's has a good stream . The only thing I can figure its the carburetor. Ive even tried seafoam and nothing it still does it. Any suggestion ?

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i had the exact same problem with my 25hp kowasaki. i would mow for half an hour fine then it would quit. it would restart with the choke pulled half way out but run rough. local mecanics were convinced it was a fuel problem. after cleaning the carb, eliminating ethenol, changing plugs, replacing fuel filter and pump, turns out the problem was an ignition coil. it would break down when it got hot. i replaced both at a cost of $95 and a couple hours. hope this saves you the agrivation i went though.

I would definitely check to see if it has spark after it gets nice and hot and shuts off, it sounds like a classic ign coil problem because it runs so long before shutting off, if it were fuel related it would shut off alot sooner. Fuel cap venting properly is something to consider too

FloGro said:

I would definitely check to see if it has spark after it gets nice and hot and shuts off, it sounds like a classic ign coil problem because it runs so long before shutting off, if it were fuel related it would shut off alot sooner. Fuel cap venting properly is something to consider too

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I think he said the cap was ok. I agree with the bad coil and it's an easy thing to check. gregjo1948

A friend of mine had a very similar problem with his riding mower. The problem was traced back to bad ignition coil.

I have replaced all the parts listed. I would like to know what the fuel pump is called. I dont think its called a fuel pump but if you were to trace the fuel line fron the carb this is the first gadget that fuel line connects to.
If I were to reverse the diagram it would be something like this:
Fuel lines from Fuel tanks to the fuel shut off switch.(At this point you can choose which tank you want fuel from.
Then from fuel shut off switch to the (Fuel pump ????) This gadget is black, round and has fuel line ports which one port goes to the carb.
Thats it in a nutshell. Any help would be appreciated.

Thanks Marty

That is the fuel pump. There should be another line(hose-tube) that goes into one of the valve covers. When the piston goes down, it pulls a suction on that hose going to the fuel pump and draws the gas from the tank to the carb. If you pull the gas line loose from the carb and crank the engine over, gas should squirt from the line. If not, check the line going to the valve cover for cracks, splits, or holes.

Lawn mower diagnosis 101.
Get an in line spark tester or better still a colortune and fit it
Get a can of starter fluid.
Remove air filter, give the mower a shot and try to start it.
If it starts but will only continue running is you keep giving it short shots of starter fluid the you have a fuel problem

If the colortune / spark tester does not flash or stops flashing before the engine starts to die, you have an ignition problem.

If you have a fuel problem the remove the float chamber and replace the cut off solenoid with a bolt/.
Engine runs OK the the solenoid or power supply to it is bad.

If the solenoid checks out OK the get a temporary fuel tank ( pinch it off your push mower )
Hook it directly to your carb and hold it as high as you can above the mower to give you the best head pressure.
Runs OK then you have a fuel pump / fuel line problem
No difference then you have a carb / manifold / valve problem.

Hook up the original fuel line again , start the engine & keep it running with short shots of starter fluid.
With a TRIGGER bottle of water/ Wd40 etc liberally spray all around the intake manifold.
Engine speed changes = air leak

Finally check the governor by starting the engine then hold the throttle open by moving the governor lever with your finger.
Works fine if you hold the lever open = governor problem

iluvfish1 said:

i had the exact same problem with my 25hp kowasaki. i would mow for half an hour fine then it would quit. it would restart with the choke pulled half way out but run rough. local mecanics were convinced it was a fuel problem. after cleaning the carb, eliminating ethenol, changing plugs, replacing fuel filter and pump, turns out the problem was an ignition coil. it would break down when it got hot. i replaced both at a cost of $95 and a couple hours. hope this saves you the agrivation i went though.

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Hello, I have an Exmark LZS801KA604 that is doing the same exact thing. I can cut grass for about 30-40 minutes and it begins to sputter like it is running out of fuel and quits. It will not crank back immediately unless I use the choke and it will crank up and run for about another 10 mins and keeps doing the same thing over and over. Did replacing the ignition coil fix your problem? Thanks

GA Fan said:

Hello, I have an Exmark LZS801KA604 that is doing the same exact thing. I can cut grass for about 30-40 minutes and it begins to sputter like it is running out of fuel and quits. It will not crank back immediately unless I use the choke and it will crank up and run for about another 10 mins and keeps doing the same thing over and over. Did replacing the ignition coil fix your problem? Thanks

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Please read the previous post and do the tests.
Also have a little think
The coils are part of the ignition system
The choke is part of the fuel system

If you can only restart by manipulating the fuel system what are the chances that your problem will be in the ignition ?

If I were a gambling man I would put my money on a plug forming in the fuel tank / tanks / switch if you have 2 tanks
But I am not so I go through the tests in the previous post because I am adversr to spending money on replacing parts that are not broken.

bertsmobile1 said:

Please read the previous post and do the tests.
Also have a little think
The coils are part of the ignition system
The choke is part of the fuel system

If you can only restart by manipulating the fuel system what are the chances that your problem will be in the ignition ?

If I were a gambling man I would put my money on a plug forming in the fuel tank / tanks / switch if you have 2 tanks
But I am not so I go through the tests in the previous post because I am adversr to spending money on replacing parts that are not broken.

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Mine only has 1 tank. I'm aware the coil is part of ignition but it's funny because the prior post lists the same exact issues mine is having and it turned out to be a coil. It's has been to the shop twice without the issue being identified or repaired.