PTO Keeps popping out once engaged

[Lance K 5]

I'm having problems with my 416-8. I have a loader attachment which has been working fine for 20+ years. In the last 6 months it has been popping out once engaged. So I need to hold the lever down (engaged) to lift the bucket or any operation involved, then drive it to where I need to dump only to have to hold lever down again. For 20+ years it never worked like that. Just put it down and good to go. I figured I might as well change the PTO clutch which was needed  and lube the bearings while apart. No problem! I was hoping that would stop the problem. Unfortunately not! I am open to any suggestions or comments! Even the Toro guy was scratching his head. I am going to replace the Nyliner Bushings and nylon shims to make operation smoother through the metal housing. I did see somewhere someone commenting about the PTO Clutch rod but cannot find the page anywhere.

[Ed Kennell 43,388]

to the  Try shortening the rod by turning the trunnion to the rear one turn at a time.

[Lance K 5]

Thanks Ed,

   I've tried up and down the threaded PTO rod with no success. I'll be checking the PTO switch tomorrow. I figure eventually I'll find it.??!!

   Thanks though.

[gwest_ca-(File Mod) 11,786]

The trunnion is installed from the bottom of the swinging bracket with the keeper pin on top?

[peter lena 9,518]

@Lance K  your unit with 20+ years  is probably  long over due  for some collective help , meaning  this is not a one and done , regularly refer to  that area , as a gold mine of opportunity,  went thru the entire set ups on mine , some related areas , in the site sent . bet  there are a number of  hang ups,  I also did over related bearings , with a clean out and lucas green chassis grease . my pto mule drive belt , spins the related bearings with  ease . note ist photo , firming up the pto lever shaft  , changed out the sloppy trundle , for a  RETHREADED  3/8 x16  to 3/8x24 , die nut ,heim joint , once you fix them , they are  very smooth / easy  , pete  

 

[peter lena 9,518]

@steelman  , original  assembly line build up  was the issue , no time alloted for  actual  detailing  .  regularly  find adding washers and lubricant , makes it better . another  thing that  really  helps  for ANGULAR  MOVEMENT  , IS HEIM JOINTS ,  they instantly react to NEXT STAGE OF  CONTINUED FORCE . they are also  usually fine thread , I  use a DIE NUT , to thread right over the original  coarse / thread, EX  3/8 x 16 vs 3/8 x 24 , dramatic smooth easy  action . my local H/W  store has bins of no thread , SHOULDER BOLTS ? those let you  build in a swing point  to a lever , washered on each side , hold a perfect lubricated setting , with a finish, elastic lock nut , dial it in . have it on pto  lever  end , also on my  plow  rod  ends , steering  rod ends . pete    

[Ed Kennell 43,388]

15 hours ago, Lance K said:

Thanks Ed,

   I've tried up and down the threaded PTO rod with no success. I'll be checking the PTO switch tomorrow. I figure eventually I'll find it.??!!

   Thanks though.

Check the spring that locks the cam at the bottom of the cam on the PTO engagement lever.    It could be weak or disconnected.    I actually added a spring on my 312 to keep more tension on the rod.  It helps to keep the PTO cam locked in the  on and off positions and stops the rattling noise.

 

[parsonsponyz 261]

[peter lena 9,518]

@Ed Kennell   ED, nothing sarcastic , hitch pin clip , right under that on frame ? turn the outer  pto cone , swing clip around , use a lighter spring , same type , and connect the two ,  as stated , that area is a , gold mine for  ENHANCEMENTS . removed my  cone brake years back , lucas green , very lightly on / in needle bearing ,  also did the , lever  improvement  , sloppy start  spot . pete 

 

 

[Lance K 5]

Just wanted to get back and to everyone. I have figured the problem of the PTO lever popping out once engaged. The problem was the PTO interlock switch which is actually 2 switches. Went to one of my spare tractors and pulled the switch after testing it for continuity. Went back to my tractor which had the problem and No continuity and replaced it with the one from spare tractor and Bingo! It no longer pops out and is holding steady. Thank you to everyone who had suggestions. I had even gone to the dealer and they had no ideas or at least would not share any info. They just kept saying to bring the tractor in. I believe I saved myself quite a bit of money on labor. A replacement switch was only $10 or so dollars the labor would have been the big expense. Doing the diagnosis would have been killer money. 

[Ed Kennell 43,388]

I'm confused, care to explain how replacing a switch solved the PTO not staying engaged problem.   Was the switch interfering with and preventing the PTO from fully engaging?

[Lance K 5]

Ed, The switch interlock was not functioning it was bent and corroded. There was no continuity through the switch at all. Snatched one off one of my parts tractors, cleaned and installed once we knew it had continuity. And Bingo the PTO stopped tripping. The one that was removed was in bad shape. I have done nothing to the tractor since the last time, when it was still tripping before removing the switch interlock and replacing. Hope that helps. I'm thinking it may be a safety switch of some sort.

Edited 12 hours ago by Lance K
Additional information

[Lance K 5]

When the PTO is engaged it presses on the 2 levers of the switches, which I would assume is the safety switch and it was kicking it out of safe operation standards for the tractor. A pretty important switch for operating the PTO I'm constantly learning about these machines.

[kpinnc 16,002]

1 hour ago, Lance K said:

I'm constantly learning about these machines

 

20+ years and I still learn new stuff. Welcome to the sickness! 

[Racinbob 12,317]

I'm with Ed on the confusion here. Was the tractor starting and running prior to the switch change? Those switches can and are often bypassed (of course they shouldn't be) and play no part in mechanically holding the PTO lever in the engaged position. Two of my tractors have that style PTO and don't even need a switch in place to mechanically operate. Can you post pictures to help us out here? 

[Ed Kennell 43,388]

Yes, the two PTO and seat safety switches functions are:

1.  one switch breaks the starting circuit preventing start up if the PTO is engaged

2. if the driver leaves the seat with the engine running and the PTO engaged the other PTO switch breaks the  ignition circuit stopping the engine 

Neither of these switches electrically disengage the PTO  although if they are badly misaligned, they may mechanically prevent the PTO lever from fully engaging.           

[953 nut 62,632]

15 minutes ago, Ed Kennell said:

Neither of these switches electrically disengage the PTO  although if they are badly misaligned, they may mechanically prevent the PTO lever from fully engaging. 

Sounds like that was what was going on.             

[Lance K 5]

Racinbob, I can't take pictures since you cannot see the switches but if you look at Ed's picture that is the style of tractor I have. It's a 416/8 I assume it is late 80's to early 90's all the info is gone.  Behind the PTO lever and tucked under the panel are the 2 switches they are mounted together. 1 of the switches was very compromised crossed over and touching the other one ( basically a short circuit ). All better now. You would not even know it is there unless you follow the wires to it. While I was in there I also changed the Nylon bushings for the PTO handle. When my son comes home he can load up a picture if he can get one. Hope this helps!

[Ed Kennell 43,388]

2 minutes ago, Lance K said:

I also changed the Nylon bushings for the PTO handle

Now I think we have the answer why the PTO now stays engaged.

[Racinbob 12,317]

5 minutes ago, Lance K said:

Racinbob, I can't take pictures since you cannot see the switches but if you look at Ed's picture that is the style of tractor I have. It's a 416/8 I assume it is late 80's to early 90's all the info is gone.  Behind the PTO lever and tucked under the panel are the 2 switches they are mounted together. 1 of the switches was very compromised crossed over and touching the other one ( basically a short circuit ). All better now. You would not even know it is there unless you follow the wires to it. While I was in there I also changed the Nylon bushings for the PTO handle. When my son comes home he can load up a picture if he can get one. Hope this helps!

 

Yupper dupper. I know them very well but I don't see them coming into play with mechanically holding the PTO engaged. 

 

4 minutes ago, Ed Kennell said:

Now I think we have the answer why the PTO now stays engaged.

 

Another yupper dupper.