Yesterday's Tractor Co. Shop Now
   Allis Chalmers Case Farmall IH Ford 8N,9N,2N Ford
   Ferguson John Deere Massey Ferguson Minn. Moline Oliver
Classified Ads
Photo Ads
Tractor Parts

Discussion Forums
Project Journals
Tractor Town
Your Stories
Show & Pull Guide
Events Calendar
Hauling Schedule

Tractor Photos
Implement Photos
Vintage Photos
Help Identify
Parts & Pieces
Stuck & Troubled
Vintage Ads
Community Album
Photo Ad Archives

Research & Info
Tractor Registry
Tip of the Day
Safety Cartoons
Tractor Values
Serial Numbers
Tune-Up Guide
Paint Codes
List Prices
Production Nbrs
Tune-Up Specs
Torque Values
3-Point Specs

Tractor Games
Just For Kids
Virtual Show
Museum Guide
Memorial Page
Feedback Form

Yesterday's Tractors Facebook Page

Related Sites
Tractor Shed
Ford 8N/9N Club
Today's Tractors
Garden Tractors
Classic Trucks
Kountry Life
Oliver, Cletrac, Co-op & Cockshutt Tractors Discussion Forum
Show Parts for Model:

over running PTO clutch question

Welcome Guest, Log in or Register
Author  [Modern View]
thompson mike

10-18-2012 11:41:48

Report to Moderator

I have an old AC rotary mower that has an over running clutch on the PTO shaft. It is worn out and no parts are available any more. If I weld it solid will it harm the PTO on my tractor currently I use it behind my 1855. Should I use one of these over running clutches you can buy at a farm store. thanks Mike

[Log in to Reply]   [No Email]

10-21-2012 11:36:10

Report to Moderator
 Re: over running PTO clutch question in reply to thompson mike, 10-18-2012 11:41:48  
I would wonder how many of those parts really are parts only available through Allis (or no longer available). I rebuilt an ORC on our NI 290 haybine as the pins and the sleeeves they were in were worn. The sleeves were more or less a drill bushing for a 1/2" drill bit, and then the pins were dowels.
I milled the sleeves out and pressed in new ones, and then the dowels just needed to be polished down with some emry cloth so they would slide freely inside the drill bushings. I think the total cost with new pins, sleeves, and springs, was under $20.

Donovan from Wisconsin

[Log in to Reply]  [No Email]
thompson mike

10-18-2012 22:09:17

Report to Moderator
 Re: over running PTO clutch question in reply to thompson mike, 10-18-2012 11:41:48  
Thanks for the input. The pto shaft has both a slip and an over running clutch. Slip clutch I was familiar with and it works as it should. Over run however is worn out where the spring loaded pins will not catch and drive the shaft. Thanks again

[Log in to Reply]  [No Email]

10-19-2012 07:22:09

Report to Moderator
 Re: over running PTO clutch question in reply to thompson mike, 10-18-2012 22:09:17  
A few things to consider in addition to the other responses. Remember that even fairly late model Allis tractors did not have true "live" pto like your Oliver does. If you wanted to change gears, you pushed in the clutch and the transmission was still coupled to the PTO. Hence, the tractor could be pushed and it was almost impossible to change gears until the mower spun down. This is why the put in overrunning clutches.

Your Oliver is totally different. You can clutch, change gears, do whatever with the transmission and it's basically 100% decoupled from the PTO hence eliminating the need for an overrunning clutch.

In addition, even when shutting off the implement, the PTO on your 1855 includes a wet type fiber brake of a single plate design. This brake can handle a reasonable amount of slipping associated with stopping a high inertial load. We have a 720 Woods and there I've had no issue applying the brake with the mower going full tile. That said, the best method is to shut off the PTO wait for it to spin down a bit, then engage the brake.

Moral of the story, that overrunning clutch is unneeded with an Oliver and is just another liability.

[Log in to Reply]  [No Email]

10-18-2012 14:48:40

Report to Moderator
 Re: over running PTO clutch question in reply to thompson mike, 10-18-2012 11:41:48  
Yes, the Allis mowers did have an overrun clutch built into the power shaft. This was a feature that I really liked about it. Personally I would repair or replace the shaft and purchase an overrun, There is a lot of energy built up in the blades and with an overrun, this will reduce the shock to the tractor's P.T.O. when you throttle down or shut the pto off. It will also help prevent the cutter from tring to "push" the tractor

[Log in to Reply]  [No Email]
John B.

10-18-2012 13:53:12

Report to Moderator
 Re: over running PTO clutch question in reply to thompson mike, 10-18-2012 11:41:48  
Seems like to me your are talking about two different things here. 1. It sounds like you mean the slip clutch in front of the mower gear box. This is meant to slip or take up shock if the blades were to hit somthing quite solid. I would update it with a newer one slip clutch, not weld the old one together. 2.An over running clutch (one way clutch) will not protect your tractor. That is only there to absorb inertia from the mower when you decellerate or take the PTO out of gear. The mower acts like a giant flywheel. On earlier model tractors without independant PTO the mower's inertia can actually backfeed power thru the pto into the transmission and keep the tractor moving even if the foot clutch is pushed in. Thus making the tractor hard to stop, especially in an emergency situation if an overrunning clutch is not used. Like I said the overrunning clutch will not protect your tractor if you hit something with the mower. I hope this makes sense.

[Log in to Reply]  [No Email]
[Options]  [Printer Friendly]  [Posting Help]  [Return to Forum]   [Log in to Reply]

Hop to:

Fast Shipping!  Most of our stocked parts ship within 24 hours (M-Th). Expedited shipping available, just call! Most prices for parts and manuals are below our competitors. Compare our super low shipping rates! We have the parts you need to repair your tractor. We are a company you can trust and have generous return policies. Shop Online Today or call our friendly sales staff toll free (800) 853-2651. [ About Us ]

Home  |  Forums

Copyright © 1997-2018 Yesterday's Tractor Co.

All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy

TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.

Yesterday's Tractors - Antique Tractor Headquarters