JD 425 AWS - Runs but quits during mowing.

[Whitey]

Good Day!

My wife's pet JD 425 (94 - 750 +- hours) has begun to give her problems. Seems she has had some starting issues the last few times she started to cut and then the mower would bog down and quit during the first 1/2 hour. Last weekend we took a look at the choke and throttle cables and the linkages in and around the carbrueator. Cleaning and lubing we thought we had the problem fixed. Alas that is not the case. She went about twenty minutes yesterday and it quit. We thought it was a fuel issue but the filter looks good and there is fuel getting to the engine. When it does run as soon as she engages the mower it bogs down and quits. Other threads have suggested a "Modulator"?

Comments?

Thanx!

 

[aczlan]

What happens if (after it stalls) you remove the fuel tank cap, then try to start the tractor?

Aaron Z

 

[Gittyup]

Have you ever had the plastic cam replaced with steel? Could also be governor gear. Does it die if you just let it idle for 20 to 30 mins under no load. If so, might suspect something electric, like fuel pump or ignition module. Also could be an issue with the pot clutch. Letting it run for long period without load should be somewhat telling.

When was last time you changed tranny fluid/filter?

 

[Whitey]

Thanks for the replys.............the good news is that it only took $20 for the part and a half hour of my wife's time to change it. It turns out that it was the modulator? The bad news is that this part is notorious for failing and is the result of many JD owners going to great lengths to figue out just what is wrong with their tractors. But since I / we belong to the greatest place ever (Tractorbynet) to find out how to fix problems from other members posts we are ahead of all the rest of the population.

I just want to thank all of you whom do your best to answer anybody's question because you never know who will be looking at a thread and learning how to fix a particular problem.:thumbsup:

 

[Nagman]

I have a 425, and had the same problem, along with rough running, would die after 10 minutes of running, black smoke, surging, have to keep the choke on, etc. My neighbor and i took the carb apart and cleaned it to within an inch of its life, installed new plugs, and a new Time Delay module. Still no luck. We then used carb cleaner and sprayed around the carb as it was running to find a vacuum leak. None found. We figured it was getting too much air and leaning it out too much. On a whim, my neighbor took a pair of needle nose pliers and pinched the little rubber hose that runs to the bottom of the carb from the carb vent solenoid. The engine IMMEDIATELY ran right. I am going to try running with that vent blocked and see how she goes.