MF 431 Intermittent Problem

Poncho · Oct 22, 2013

I've been having a problem that is intermittent. The tractor has 540 hours on it, and it winds up just shutting off. Last year while cutting food plots and shooting lanes at the hunt lease, it just died... all lights flashed and then it went cold, wouldn't turn over, and nothing would come on (new battery). Checked fuses etc., after tinkering and for no reason that I can explain.. it decided it would crank after a while... had no issue after that or the rest of the year. Well, in woods again this year... and it acted up again. This time it would bog and die when accelerating... would turn over but wouldn't crank. Did notice that you couldn't hear the fuel pump, then it would kick on and it would crank... as soon as I applied juice, it would bog and die and then crank but no start, and the same issue with pump would start. The only thing i did was drain some fuel in case there was water in the filter. After a while of start and cut-off several times, It stayed running with no issues for 3 hours after that. The cutting off and on for not reason puzzles me, but I do remember finding a rats nest under the cowl and am thinking I may have a short somewhere but am wondering if I might also have a fuel pump issue. Anybody have any other thoughts?

thanks

SDT · Oct 24, 2013

Poncho said:
I've been having a problem that is intermittent. The tractor has 540 hours on it, and it winds up just shutting off. Last year while cutting food plots and shooting lanes at the hunt lease, it just died... all lights flashed and then it went cold, wouldn't turn over, and nothing would come on (new battery). Checked fuses etc., after tinkering and for no reason that I can explain.. it decided it would crank after a while... had no issue after that or the rest of the year. Well, in woods again this year... and it acted up again. This time it would bog and die when accelerating... would turn over but wouldn't crank. Did notice that you couldn't hear the fuel pump, then it would kick on and it would crank... as soon as I applied juice, it would bog and die and then crank but no start, and the same issue with pump would start. The only thing i did was drain some fuel in case there was water in the filter. After a while of start and cut-off several times, It stayed running with no issues for 3 hours after that. The cutting off and on for not reason puzzles me, but I do remember finding a rats nest under the cowl and am thinking I may have a short somewhere but am wondering if I might also have a fuel pump issue. Anybody have any other thoughts?

thanks

Sure sounds like a fuel pump issue.

I have a 533 which is a bit newer but nearly identical. The fuel pump must run for the engine to run at much more than idle.

Last fall I bought a new 2635. As delivered, the fuel pump operated intermittently. It turns out that the electrical connections at the pump had not been tightened.

In your case, I suspect rodent damage somewhere in the wireing harness.

SDT

Poncho · Oct 24, 2013

SDT, Thanks... that's what I'm suspecting, but wanted to see if someone had other ideas. Thanks a bunch for the response

MFRED · Oct 25, 2013

I think there's a connection point under the top hood panel that gave some grief. Same side as the fuel pump fastened to the hood about half way to the front. Connects the engine electrical to the dash. It may have come loose giving an intermittent issue.

Poncho · Oct 27, 2013

MFRED, Thanks! I will look for that.

Poncho · Oct 7, 2014

Well, sorry to revive an old thread, but I think I finally found the problem. After pulling all panels off and checking all wiring (none was chewed by rats.... everything was intact), I decided just in case that I would replace the ignition switch. When I went to remove the ignition switch, I discovered that one of the clips was only making metal to metal contact at the end and the plastic outer shell was holding it in place. After replacing the ignition switch and crimping the clip for a tighter fit, I've not had any issues so far after a few hours seat time in the woods and also bush-hogging the back pasture. I also had to replace the fuel line from the top of the tank to the pump as it seemed to be seeping fuel, so I replaced that also. Hopefully this info will prove beneficial to someone else searching. I'm certainly not as knowledgeable as many of you on here and glad it turned out to be something simple.

masseyrider · Oct 8, 2014

If you have the same fuel lines as the 563, yeah, they don't last long. Minor pain in the *** repair. One of my 563s has a loose clip on the safety switch down below the PTO lever. It sometimes falls off and kills the tractor ignition system. If it happens while running some of the idiot lights on the dash light up.