[mello_collins]

318 front pto help please

My 318 front pto started acting sluggish this summer. Engaging slower and slower. Planned on tearing into the pto for my first time after the leaves had stopped. No such luck. This past weekend getting the leaves up at my mothers it repeatedly kicked out. All of my safeties checked out, so I was fairly certain the problem was with the pto given it’s previous sluggishness.

Found the gap set to nothing. Less than 1 thousandth. Started to take it off. Had to bang on the both the pulley and inner friction drum to get them off while using penetrating oil. The shaft had surface corrosion and the inside surfaces that rode on it. Got most of that off. Found the clutch surfaces slightly scored and some burrs. They cleaned up with sand paper and a wire wheel. Found some bubbling on the bottom portion of the field coil. The crud behind the coil was amazing. I try to keep her clean, but had never gotten behind the coil clean apparently. Cleaned every thing up and put it back together. Set the gap and she worked better than she had in awhile. Real trial will be this weekend when I load up and head back to battle my mom’s leaves.

I figure my problems are related to heat from the crud behind the field coil and corrosion on the stub shaft binding up the clutch. I have ordered a new field coil. Darn expensive little piece. I assume I need to polish up the shaft from the engine and the inner bearing surfaces that ride on it. Any recommendations for a home tinker as to the best way to do this? And what should I put on the shaft as a lubricant to prevent the parts seizing up again. Trying to figure out what will stand up to the heat, last a long time, and not attract the dust from yard work. Any advice is appreciated.

 

[jdmaninlouky]

Michael -

Sounds like you have the matter under control . I might add to check the bearing , and replace if it is suspected to be dry/worn . Slide the bearing and rotor on the shaft without any other pieces to see if there is excessive lateral wobble , then be sure the bearing is silky smooth or not . I have popped the rubber seals out and cleaned and re-lubed the bearings also , but it can be a bit of trick to get the seals out cleanly without distorting them .

Being a slip fitment , I would just use a bit of any old oil on the shaft to bearing race interface

Good luck and keep us posted :

Dave

 

[dkarst]

I would second David's recommendation on giving the bearing a look. As for the shaft and lube, I would very gently use a bit of very fine emery paper with a little WD40 to smooth things and I would use a little never seize to keep things lubed.

Remember to engage a couple times and go around the gaps a couple times to check for 0.018"

If you are getting that much crud behind field coil, is the main oil seal weeping as that will build up stuff in a hurry.

 

[mello_collins]

Front main oil seal is good. Dry as a bone behind field coil. I am just going to add a r&r of the front pto to my yearly spring maintenance. Got the shaft polished using a bar of metal polish and an old oven mit. That went smooth and I still have all of my fingers. Dropped off the plate that sits in front of coil to see it they can mount it on a rotor lath and clean it up. Bearing seams smooth, polished inside it and the plate in front of coil with dremel and the same metal polish. I have some never seize, but am worried about it slinging onto the friction plate. I'll try it. The worst that can happen is the need to remove and clean it off. Anything else y'all can think of? And what is the proper routing for the wire going forward to the pto.

 

[dkarst]

Not so much never seize that it can get slinged anywhere... just a thin film.

 

[mello_collins]

Works like a charm now. The old field coil ohms out ok. I'll keep it as a spare, just in case. I now get a satisfying clunk when I engage the pto with the tractor not running. Word to the wise. If you have never taken yours off then do so. Maybe you can keep yours from binding up. Mine performs better than when I got the ol' girl 5 years ago.