fjc-man
SILVER Star
My question is, how much load do you estimate this could handle before the sheer pin gives up?
1976 OEM PTO winch
- Thread starter fjc-man
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TEakins
Ted
If you will sell it to me I will let you know after some testing.
It’s rated 1500 kg. Change the pin and you can 2x or 3x it easily.
The sheer pin on my "stock" Toyota PTO is only 1/8" in diameter.. The metal "appears" to be cast iron.. I've sheered three pins
over the 27 years of daily driving (farm work, hunting, etc. It wasn't "babied") and the "point-of-sheer" was always as clean as
a "knife cut".. but then, the pins fit "perfectly tight".. no "slop" at all. I might add that I only use the stock Toyota Sheer Pins..
I last bought some in the mid-'90's.. cost about $2ea.. I don't know if they are still available (from the dealership) or not..
Charles 1974 FJ40.
Isn't a "kilogram" 2.2pounds?? If so, that make your "1500KG" rating ONLY 3300 Pounds!! Isn't the stock Toyota PTO Winch rated
is up around 9,000 10,000lbs... plus or minus a bit??
Charles 1974 FJ40.
Mark Whatley (of Mud fame) years ago said you could drill out the shear pin hole and use a 1/4-20 fastener (mild) and gain a lot of pulling power. But by doing this, the force is transferred downstream to other drive train components.
I have broken a lot of shear pins trying to pull stumps and such, and agree that the factory PTO setup is very conservative on what it will pull before shearing the pin. I have no idea what force is required to shear the pin, but it was less than I would have liked. I only used OEM pins.
IMO, if you want serious pulling power, get an 8274 and skip the PTO winch.
More reading:
forum.ih8mud.com
forum.ih8mud.com
I have broken a lot of shear pins trying to pull stumps and such, and agree that the factory PTO setup is very conservative on what it will pull before shearing the pin. I have no idea what force is required to shear the pin, but it was less than I would have liked. I only used OEM pins.
IMO, if you want serious pulling power, get an 8274 and skip the PTO winch.
More reading:
PTO vs Electric
forum.ih8mud.com
Toyota PTO winch rated capacity....
forum.ih8mud.com
Last edited:
On some topics I saw advice to use 70 series shear pin which is a little more resistant.
But the 70 shear pin is 5mm versus 4mm for the 40 one so I don't see how it could fit without drilling.
Putting a bolt instead of the shear pin is also losing every bit of safety on this winch. Just imagine if it engages while driving without a shear pin...
But the 70 shear pin is 5mm versus 4mm for the 40 one so I don't see how it could fit without drilling.
Putting a bolt instead of the shear pin is also losing every bit of safety on this winch. Just imagine if it engages while driving without a shear pin...
according to the operator instructions for the PTO winch it said " Do not exceed the 1 1/2 ton capacity of the winch. pulling heavier loads may cause the safety pin to sear off " So there ya go
I’m not suggesting anything, just telling. Bad idea or not, but it’s not very useful with the original pin in serious offroading. I’ve seen a lot of abuse, the PTO winch itself is very strong, other components can handle easily 2-3 times more than adverised with the original pin.
Living in the Past
SILVER Star
Don't remember a tow using an electric winch. For serious pulling power they looking for more than once really just a beefed up starter motor. Engine doesn't over heat on long pulls. It was old CJ5 with a PTO winch and a seventies 1/2 ton chevy pickup. Jeep was a couple of teenagers were on the Rubicon. Drove until they got stuck in the snow. One kid would run out with the cable to the end of the drum. Throw it around a tree and pull the jeep. Then repeat until there were out of sight. This was in 1975. The chevy truck was early eighties. November on a elk at 8,000' north of Flagstaff. A CJ7 had slid off a forest service road and the pickup was working on getting it back on the road. It was dark and could see the lights dim every time he started to pull. Took over thirty minutes for a simple pull battery and alternator were not up to the task. Once an engine is started battery is not need. All the power an engine creates going to a PTO can't be matched by an electric winch.
I agree the shear pin is rated to break long before anything else. The pillow block bearing with the aluminum housing is a rare part to replace if it breaks. It could possibly be the next weakest link. 1/79 Toyota redesigned that to a steel housing mounted to the frame rail verses off the radiator support bracket. Not a fan possibly moving the weakest link to something other than the shear pin. Just a simple snatch block pulley can reduce the load by half. Unlike an electric winch a PTO is capable of speeding up by transmission gear or engine running faster.
If someone within the Toyota network can get some material specifications for the OEM shear pin I can calculate the pulling force that will shear the pin.
fjc-man
SILVER Star
- Thread starter
- #13
Steve, would you happen to know the shear/sheer pin part number?Mark Whatley (of Mud fame) years ago said you could drill out the shear pin hole and use a 1/4-20 fastener (mild) and gain a lot of pulling power. But by doing this, the force is transferred downstream to other drive train components.
I have broken a lot of shear pins trying to pull stumps and such, and agree that the factory PTO setup is very conservative on what it will pull before shearing the pin. I have no idea what force is required to shear the pin, but it was less than I would have liked. I only used OEM pins.
IMO, if you want serious pulling power, get an 8274 and skip the PTO winch.
More reading:
PTO vs Electric
Toyota PTO winch rated capacity....
90255-04001
Because I have broken a few pins this question got me thinking, my maths has problems with the grocery bill so calculating is not for me, decided to do a test so I made a jig with a 1 inch shaft and a little clearance in the hole - as I have seen on the new PTO winches I've had from Toyota over the last 50 years - made 2 holes so I could test the early pin 001 that is a little thinner than the later pin 002 (from late 84)
The hole sizes I got from shafts I have in my used spares box from the many winch repairs done over the years - in the end I only had the later 002 shear pins so the test was done with that size only
Used a tension wrench and started at 40ft lb, went up 5lb at a time, had no feeling of turning until 140ft lb and at 145ft lb the Toyota shear pin 002 cleanly broke, as soon as I felt a little give it "fell" away cleanly. Tested a pin again at 145 and it did the same.
Then after much looking around I found an ordinary builders 4 inch bullet head nail of a diameter size within a few 'thou of the Toyota 002 pin, and it did the same - at 145ft lb a slight give then a fall away. Tried again and got the same result.
Note - the holes were rubbed a little with emery on a finger so there was no sharp to the touch "cutting edge" but they were not in any real way "rounded/radiused".
So, unscientific and all a bit of "eyeball engineering" but mild steel (as I expect the nails to be) seems to be about the same as the Toyota pin.
This was just so I have an idea of how it all goes but I will still use the Toyota shear pin to be safe and protect the expensive bits, the pins are in the scheme of things cheap so best to use them.
Finally, as said over the years I've rebuilt a few Toyota PTO winch setups and one issue to note, if your PTO shaft to hookes joint piece is a sloppy fit the joint will flog around in use and wear the shear pin down a bit and then they shear much easier than expected, the fix is a lot of fiddling around but you machine 2 rings and a stepped temporary inner alignment tube and weld the rings on - preheat to very hot and tig weld - the rings will bear on the unworn part of the worn shaft and give you a bit more use before that flogs out and you have to get the shaft spray welded up and machined back to size. wil post pics for than next
Finally (again) if the holes for the pin are flogged out you can drill a ne hole at 90deg around but you need a jig to ensure you are drilling straight and central and you can do the matching holes around say 30deg (by memory) on the hookes joint yoke but again it has to be done exactly straight and central - another jig. I made the jigs years ago and cannot find them now - will have to make new ones next time to job comes up.
Cheers from Australia
pics for the fix to get a bit more life out of a flogged out PTO hookes joint, note - here the hookes yoke is not too worn but the PTO worm shaft is very worn where the yoke "covers". The steel bushes to be welded on will cover the unworn parts of the PTO worm shaft and keep the yoke running reasonably true for a bit longer so as to not flog out the shear pin with speed wobbles.
Cheers from Australia
Cheers from Australia
