First of all
![2516717]()
...did you knock the wires off the PTO itself at the shaft?....I know that @PA318Guy will see this and be able to tell you exactly what the problem is...he has that user name for a reason 
John Deere 318 PTO will not engage
Need some help with troubleshooting.
Dad and I put on a new muffler, and took the PTO off to do so. When we put it back on, the PTO would not engage. we were sure that it was because the clutch wasn't gapped to 018. I gapped it exactly to 018 at all 3 points, and it still won't engage. I get 12 volts at the junction where the PTO connects. The switch lights up the engagement light on the dash.
I believe it's important to note - I hear no click when I turn the PTO switch on.
Any advice would be helpful!
Dad and I put on a new muffler, and took the PTO off to do so. When we put it back on, the PTO would not engage. we were sure that it was because the clutch wasn't gapped to 018. I gapped it exactly to 018 at all 3 points, and it still won't engage. I get 12 volts at the junction where the PTO connects. The switch lights up the engagement light on the dash.
I believe it's important to note - I hear no click when I turn the PTO switch on.
Any advice would be helpful!
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Welcome to MTF jda08! I would check fuses at this point.
It's possible that you pinched the wires to the pto when you reinstalled. If pto light is on, fuse, seat switch, and pto switch are OK. Some wrong between pto switch and pto windings amd this is further verified by 12 volts at the connect. Bob
Thanks Everyone - still no resolution; checked fuses; they're solid. took PTO off and stripped connections a few cm's to get leads connected. I have 11.45v heading into the PTO when I turn switch on. still no engagement. Will check ount @joneill4 's video and see if that may be the issue. Welcome any other thoughts.
Does the connector have both power AND ground with the pto switch on?
affirm - voltage measured between the two leads of the connector to the PTO; when connected, measured voltage between the two wires heading directly into the PTO. will try to take a picture of what I'm measuring.Does the connector have both power AND ground with the pto switch on?
Can the plug possibly be reversed (they typically are keyed to only go together one way, but sometimes you can force them together the wrong way)?
Check the resistance between the two connectors on the pto (when disconnected), it should be a fairly low resistance (around 2-4 ohms). If it's a lot more or a short, then the pto needs fixing/replacing.
Check the resistance between the two connectors on the pto (when disconnected), it should be a fairly low resistance (around 2-4 ohms). If it's a lot more or a short, then the pto needs fixing/replacing.
dave_r gave excellent advice to check the resistance of the PTO.
What about when you measure the resistance at the plug?
The ohms - 3.8 - may not be good, may be low. Friend tells me 3.9 is at the low end. 3.9 to 4.9 is normal.
Field coil on that thing alright? That electric PTO clutch did work OK before the muffler replacement?
You can actually gap it lower\tighter than 0.18 to see if it may engage - - but then run the risk of ruining it.
All the wiring OK - including grounds and the seat safety switch?
Field coil on that thing alright? That electric PTO clutch did work OK before the muffler replacement?
You can actually gap it lower\tighter than 0.18 to see if it may engage - - but then run the risk of ruining it.
All the wiring OK - including grounds and the seat safety switch?
Given that you have the pto off the crankshaft, perhaps try (carefully), directly connecting two short 10-12 gauge wires directly from the battery to the clutch and see if it engages? If it does, the problem is elsewhere, if it doesn't, it's the pto.
One more meter check. Check each wire for continuity/resistance to pto case, should be open/infinite resistance. Bob
I'd say 11.33V is a little low. A slightly weak voltage and a slightly weak coil could be your problem.
You can also try taking a 1/4 turn on each clutch adjustment bolt, try it, and then take another 1/4 turn and repeat. If it is weak coil/voltage, at some point your gap will get small enough to pull it in. May not want to leave it at a very narrow gap, but it would provide info to your issue.
You can also try taking a 1/4 turn on each clutch adjustment bolt, try it, and then take another 1/4 turn and repeat. If it is weak coil/voltage, at some point your gap will get small enough to pull it in. May not want to leave it at a very narrow gap, but it would provide info to your issue.
I would check the the key switch, fuse holders for corrosion, the PTO switch to see if the internals have some pits due to arcing on contact closure. I would also check the TDC module plugs for corrosion also. Those could cause an additive voltage drop. Remember you should see battery voltage all the way through the wiring chain, anything less is loose connection or corroded connection.
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