PTO Poppet washer

[Tackettr]

I just rebuilt my PTO and having problems shifting it.

The copper washer that fits on the poppet retainer looks pretty flat. When I tighten the poppet retainer down it puts too much force on the shifter rail and locks it in place. I can't budge the shift lever even with my foot! If I back the retainer out a few turns it shifts normal.

How thick should the copper washer be, or can you use two?

 

[gringeltaube]

That copper washer is only intended as a gasket, not a shim! If you used teflon tape or sealant instead of a metal gasket it should make no difference in the mechanical function.
So your problem is somewhere else. Possibly incorrect coil spring bottoming out to soon? (IIRC the poppet ball was missing....)

Check following measurements, just in case:

• lenght of threaded portion on retainer: .595"
• distance from machined surface on housing to shift rod: .657"
• spring lenght, free: approx. 1.5"
• spring lenght, compressed: .75"
• coil outer diameter: .475"

You can also do a simple bench test, by pushing the retainer down onto a flat surface with the spring and ball in place. The ball should easily go in all the way to be flush with the retainer's opening by just applying enough force with your fingers.

Let us know what you found!

G.

 

[Tackettr]

gringeltaube:

Thanks for your help again. I checked your measurements against mine and they were good. I wasn't able to do the "distance from machined surface on housing to shift rod: .657", because I have it mounted and full of oil.

I even ordered new stuff from Memphis Equip. just in case the spring had too much tension.

Findings: Nothing worked! If you only use one washer or even two, you can not shift it. I had to put 3 washers on it to get it to shift.

I don't have time right now to drain it because I have a parade this weekend. My next measurement will be the one above. I don't know how this could be the problem. The shift rail and detents looked perfect during rebuild. I can't believe something this simple is causing me problems.

Thanks again for your time and help.

 

[Jake0147]

If that distance were inaccurate, I think either you couldn't have rebuilt it, or you couldn't have filled it with oil. When I got my new (to me) pto, I had the same thing, except I rectified it before installation. 40 years of transmission wearings underneath the bearing wouldn't let it drop far enough to allow movement. That's one possibility, after i cleaned that it bound up intermittantly. (One in four "cycles" maybe?) look for the ball to be worn a bit, with the slightly removed area allowing the spring to wedge between the bearing and the retainer and restrict movement.
With a brand new bearing and a brand new cleaning of the "cup" inside of that retainer, mine shifted just fine without any sealing washer at all, or with the correct one installed.

 

[gringeltaube]

Well, this all can't be no mystery.... !
I'm assuming the retainer cup was inspected & cleaned inside before assembly...? ...also, that a NEW bearing ball was installed??
What about spring size and rate? What I believe is the std. size has a wire diam. of .063" with about 10-11 windings but I have also found some stronger ones installed (less coils and .075" wire). Compressed they are both the same lenght, that is 3/4". One can feel the difference as it is a little harder to shift but that's all.

Attached is a little drawing in correct proportion to help visualize the relative position of all parts involved and their function.
All very basic for sure; hard to imagine what could be causing the problem...

G.

 

[cranetruck]

Got nothing to add, just admire your drawings Gerhard.

 

[Tackettr]

Thanks for all the help guys. Right now it has a new retainer and ball from Memphis. I went with the old spring because it was easier to compress and it goes down to 3/4". Without the spring in the retainer, the ball will drop all the way down to the bottom no problem. This simple little problem is really kicking my butt!

After my parade duty, I am going to drain it and do more checking, I haven't tried no washer. I thinking the ball may be jamming against the side if the retainer isn't close enough. Thanks again everyone.

 

[gringeltaube]

................. I thinking the ball may be jamming against the side if the retainer isn't close enough.................

Wanna bet? Install that retainer with some teflon tape only -> problem solved!

G.

 

[gringeltaube]

................ just admire your drawings Gerhard.

Thank you!! I got used to draw and (re)design stuff using simple tools like triangle and compass for about 30years... then I "discovered" the advantages of MS-Paint which hopefully will help getting me through the next 30....!?

(Is it MV related? Maybe, could be, depends....... )

G.

 

[Tackettr]

Follow up: gringletaube was correct!!! I removed the copper washer and only used teflon tape and now it shifts normal! I con only guess that using a washer created too much space and allow the ball to jam between the shift rail and housing. Thanks for the help grigletaube!!

 

[clinto]

Gringeltaube is truly one of our expert "deuce whisperers"-all we need to do now is convince him to plant his antisocial backside into an airplane seat and come to some of our rallies!