318 with pto electrical gremlin, HELP

1470 Views 10 Replies 5 Participants Last post by mrgreen, May 8, 2013

Dieselrig

Discussion Starter · Dec 13, 2005

I had a magnet go bad, and replaced that, still doesnt work, put on a new switch and it worked a couple times in the garage, now nothing, the dealer says a bad or broken wire or a time delay box, what does anyone suggest from here, please help before it snows again, thanks

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Jd318_mazz

· #2 · Dec 14, 2005

Mike - Specifically, what is the issue? Is the PTO not engaging at all? Have you adjusted the air gap? If the gap is too wide, the PTO won't engage, or if it does, it can be intermittent. Gap should be 0.018". There are three lock nuts around the perimeter of the clutch. Insert a feeler gage into one slot, and adjust the adjacent nut. Repeat at the other locations, and go around a couple more times to fine tune the adjustment.

Might also want to look at the 20 amp fuse, to see if it's blowing. If so, you may have a bad wire shorting out, or the field coil is bad. If the fuse is not blown, the field coil can still be suspect. However, you indicated you replaced the magnet (field coil).

Also, is the battery up to the task? A weak battery can lead to PTO failure. So can an electrical charging system that does not put out enough. If the charging system is not putting out enough voltage, the PTO can fail to engage.

Those are some ideas. If you can provide some more specific information, it might help to diagnose the problem a bit better.

Dave

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Dieselrig

Discussion Starter · #3 · Dec 14, 2005

Good points Dave, I did adjust the air gap and centered the magnet just like the dealer had said, and it works good by touching a test wire to the battery, but through a brand new switch, it just once in a while gets it to engage, I did see my battery light on very dimly tonite, so I guess this could cause it, but still works with a test wire, or is the time delay box that sensitive with voltage, if this box is bad, can it be bypassed, I am pretty creative with wires, but would there be other issues, I noticed with the bad switch not hooked up the tractor would not even turn over to start, with it hooked up, started right up, no pto still, but at least could move it to allow the wifes car in!! any more ideas??

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Jd318_mazz

· #4 · Dec 14, 2005

If the TDC module is bad, I would not want to try and bypass it. You'd end up having to bugger up the wiring in order to do so. There is a test for the TDC that you might want to do before plunking down the several hundred dollars that thing costs. Do you have the Tech Manual for the 318? The test is in there. But if the PTO is the only issue you are having, I'd be looking at a bad connection or bad wire. Have you checked the main ground? It's usually located behind the battery (yeah you gotta pull the battery)? A lot of times, if you loosen that up, sand the area, and retighten the ground, things come back into normalcy. Just another thought.

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Dieselrig

Discussion Starter · #5 · Dec 14, 2005

I didnt check that, I do notice that I have a very dim battery light, although the battery is charging good, as a matter of fact, I just put in a new battery for good measure, when I flip the pto switch, the battery light gets brighter for just a second then back to dim, pto will work with a jumper wire to the battery, but when you try to mover the tractor, it shuts off, so that ends the quest for trying to put on another switch to fix it, the dealer says that I must have a bad wire too, but the wire from the pto magnet to the wire that goes onto the switch (light blue) shows 0 ohms , so it has to be good, fuses are good, I am just lost on this one. I dont have the manual to try to test the TDC, keep the ideas coming, we have to get this fixed , 3to 6 tonite here in western Pa.

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flymo

· #6 · Dec 14, 2005

Mike, on my old 317 the main power connection way down in the guts was loose and dirty, so it would show voltage, but not pull any current. So as soon as I hit the PTO switch, the whole tractor died. Drove me nuts for several years until I found it. The connection I had trouble with was from the starter solenoid to the main wiring harness - don't know if it's the same on your 318, but the symptoms sound very similar. I think if you trace and the whole path from the battery to the PTO, cleaning connectors as you go, you'll be on the right track.

Tim

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Dieselrig

Discussion Starter · #7 · Dec 15, 2005

I will try that too, yeah it does seem like a ground problem to me too, the more I think about it, guys , is that main ground under the battery tray easy to see?

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Dieselrig

Discussion Starter · #8 · Dec 17, 2005

guys, great news , the wire harness ground was the problem, it was not very clean at all and once that was cleaned, the pto worked perfect and the lights were even brighter, just in time to get the new snow blown out of the driveway, you guys are great , thanks again for getting me heading in the right direction, Mike

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