Grasshopper 725 problem

[pmac0101]

I have a 725G2 (kubota wg752)that will not run once the PTO is engaged. It starts and runs through all RPMs fine. However, once the blades are turned on it just dies. Sometimes it will run for a minute or so, and then other times, it dies as soon as they are engaged. I have changed plugs, new fuel filter, took the carb completely off and a thoroughly cleaned it, checked all electrical connections, removed fuel tank, drained all old fuel and checked for stopped vent hole, etc. Just to make sure, I happened to have another fuel pump on hand and replaced it. Same results.

I love my Grasshopper, but one of the things that drives me nuts is the "top secret" nature of trying to obtain any information, help or service manuals, etc. I have searched extensively and it seems almost impossible to find anything on them.

In the interest of full disclosure, I had a similar problem like this last year, it was finally fixed after almost six weeks at the dealers. I stopped by a couple of times, during the repair, and he had been on the phone with kubota and grasshopper several times. I saw the check sheet they sent him, and it was over six pages long. It seemed to be frustrating to them also. It ended up being some type of diode, forward diode or something like that, I really can't recall.

I was planning on doing some limited mowing for extra income this summer, which was why I got it out in February, and then this happens. I have a good dealer, and am not trying to take $$$ from him, but I like to know how to fix my own stuff, and figure that if these things happen out in the field I can repair myself instead of taking it into the shop for a week or two "vacation".

If anyone has any ideas, I would be extremely greatful and appreciative!!

Thanks,
pmac

[Restrorob]

pmac,

I would suggest putting a in-line spark tester on one of the plugs, Start the unit and watch the tester seeing if it drops spark when it dies.

I'm not familiar with Grasshopper unit's but this is a basic test to determine if it's a fuel or ignition problem.

I want to think it sounds like a seat safety switch or pto switch (there's a safety switch in it as well) problem. These switches can be tested by un-plugging them and using a multimeter set on ohm's scale. Put the tester leads across the switch post then activate the switch.

Good Luck

[Sammy]

Another thing you can try is:
Disconnect the clutch by unplugging it, then try the switch. If it dies, your problem will be from the clutch plug up to and including the switch. If it does not die, then your problem may be the clutch. Make sure your battery has a full charge in it when you do this.

[Sammy]

Guess he ai'nt coming back to tell us what the fix was.

[Two Seasons]

That "forward" diode that was replaced last year was more likely to be a steering diode used in the rectifier and used to re-charge the battery.

Make sure your battery is fully charged too.

I like the switch bypass and the PTO bypass suggestions too.

Let us know if you have it fixed.

[hornet506]

he must have fixed it...
That liquid cooled kubota engine is bullet proof, that surprises me.