318 ignition/PTO problem

[brosenow]

First time posting to this forum, got a 1985 318 with the house I bought. 4 or 5 years ago the coil went out and the JD dealership put in a new one. The tractor ran fine and then about 2 years ago the tractor started burning thru a set of points and plugs every year. Took it to a guy that works on lawn tractors (not JD dealer) and he told me the new coil that was put in is bad and causing all the problems. He advised putting in a electronic ignition and new coil for the tractor as well as replacing everything the new coil had burned out, I said yes. The tractor now runs great except for 2 things. The battery light is on even thou it appears to be charging the battery fine and the PTO will not stay engaged for the mower deck. Just shuts off by itself after being engaged. I thought it might be the new electronic ignition causing this, but he says that they are two different systems and this is a new problem. If the PTO does engage the light for the battery goes out, but the PTO stays engaged only about 10 seconds before disengaging by itself. Has anyone seen or heard of this problem? Is this a timing switch/module problem, this guy thinks that is what the problem is? If so, what needs to be done or checked before I have this replaced? The PTO switch appears to be working correctly. Thanks, Brad

 

[Hammermechanicman]

Without a schematic and knowing EXACTLY what he did to the wiring everything will just be a guess. From what you describe the pto worked fine till he worked on the wiring. We have no idea what he has done to the wiring.
He "thinks" the module is bad. Kind of a red flag to me.

 

[StarTech]

 

[Deleted member 97405]

First unplug the connector at the PTO clutch in front of the engine. Make sure you have voltage when you turn on the PTO switch. If you do, proceed. If not, get voltage first. Then read on. Sounds like your PTO clutch coil is shorted and needs replaced. Over time, the coil ages due to use, heat cycles, etc. The coating over the windings gets brittle and cracks. This lets in moisture as well as allows the coil to short out. This is common on this series. When they start to go bad, they usually run for a bit, then shut down once they heat up. Then, over time, the intervals get shorter, until you get no PTO at all. Other times, it's a sudden failure, no warning. Not a hard job, but I would recommend letting somebody do it if you're not familiar with using feeler gauges. Oh, FYI, while they're in there, replace the front crankshaft seal while they're looking right at it, even if it's not leaking. Nothing worse than putting on a new PTO coil only to get it coated with oil shortly after.

 

[DaveTN]

Could be the wire going in on the PTO clutch making intermittent connections. I've seen same type thing on
blade clutches as well.

 

[Deleted member 97405]

If the coil went bad, it could have melted/distorted the connector. Good point.