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Toyota PTO Winch shear pins
Posted: Sat Sep 17, 2005 10:53 am
by CT
I'm trying to figure out what the correct shear pin is for my factory Toyota PTO winch. Thomas in Brisbane told me that they were simply 3/16 copper rod. I tried that and I reckon that it's way to weak. Maybe the shear pin loads of the Thomas winches are different to the Toyota ones.
Any ideas? What do other people use?
Hoping not to have to resort to a bent nail just yet!
Cheers
Craig
Re: Toyota PTO Winch shear pins
Posted: Sat Sep 17, 2005 12:37 pm
by dumbdunce
CT wrote:I'm trying to figure out what the correct shear pin is for my factory Toyota PTO winch. Thomas in Brisbane told me that they were simply 3/16 copper rod. I tried that and I reckon that it's way to weak. Maybe the shear pin loads of the Thomas winches are different to the Toyota ones.
Any ideas? What do other people use?
Hoping not to have to resort to a bent nail just yet!
Cheers
Craig
I made a bunch out of 3/16" mild steel and found that they were breaking too easily so I drilled out to 1/4" and used a M6 bolt through, never came close to breaking the winch or the drive or the cable but the pin still went occasionally. 1/4" bright bar might be the go, it is cold rolled so is a bit work hardened so will sher at slightly higher stress.
ats
Posted: Sun Sep 18, 2005 4:50 am
by rockcrawler31
try calling ATS (advanced trailer spares) assuming their not the thomas supplier you were speaking of. they fitted my pto and know their business very well.
Posted: Mon Sep 19, 2005 5:06 pm
by MattGU
stop trying to pull trees over in your back yard
Matt
Posted: Mon Sep 19, 2005 9:17 pm
by CT
MattGU wrote:stop trying to pull trees over in your back yard
Matt
Well get up here with a shovel and help me dig them out!
Re: Toyota PTO Winch shear pins
Posted: Mon Sep 19, 2005 9:21 pm
by CT
I made a bunch out of 3/16" mild steel and found that they were breaking too easily so I drilled out to 1/4" and used a M6 bolt through, never came close to breaking the winch or the drive or the cable but the pin still went occasionally. 1/4" bright bar might be the go, it is cold rolled so is a bit work hardened so will sher at slightly higher stress.[/quote]
Dumbdunce,
When you drilled out the main shaft of the winch motor, was the shaft hardened steel or was it easy drilling. Here's hoping not to have to take the motor apart.
Rockcrawler,
Got on to ATS. They use 1/4 copper rod. Might have to combine this with Dumbdunces drilling idea.
Cheers all
Craig
Re: Toyota PTO Winch shear pins
Posted: Tue Sep 20, 2005 11:17 am
by dumbdunce
CT wrote:
Dumbdunce,
When you drilled out the main shaft of the winch motor, was the shaft hardened steel or was it easy drilling. Here's hoping not to have to take the motor apart.
yes it is hardened, but drillable with a HSS drill bit - it is only case hardened so once you get through the surface it drills eaasily. you might need to do sharpen the drill a couple of times to get it through but if you take it slow and get someone to squirt WD40 on it as you go, it will go through.
Posted: Fri Sep 23, 2005 10:54 pm
by wanna
Talk to power auto get a torque limiting coupling easy automatic ajustable no more shear pin i got one looks great phone 0397912255
Posted: Sun Sep 25, 2005 8:09 pm
by CT
Where abouts does the coupling fit? Same place as the shear pin Uni?
Sounds like a good idea. Can you remember what you paid? Any pics?
Does it just stall like an electric winch, or does it release into a free spool mode similar to when a shear pin breaks? I'm a bit worried about dropping the ute back into something if a pin breaks and this might be a way around it.
Sorry about 20 questions but I haven't heard of this option before.
Cheers
Craig
Posted: Sun Sep 25, 2005 10:09 pm
by dumbdunce
CT wrote:
Does it just stall like an electric winch, or does it release into a free spool mode similar to when a shear pin breaks? I'm a bit worried about dropping the ute back into something if a pin breaks and this might be a way around it.
Sorry about 20 questions but I haven't heard of this option before.
Cheers
Craig
a PTO won't free spool when the shear pin breaks, there is far too much friction in the worm gear for it to be driven backwards - the more load that is applied to the cable the more it will lock.
it works the same as a shear pin except that nothing breaks, so if it overloads it just stops, then you can back it off and set up a souble line pull or different line, so you never have to get out in the mud and replace anything.
Posted: Mon Sep 26, 2005 1:03 pm
by CT
[/quote]
a PTO won't free spool when the shear pin breaks, there is far too much friction in the worm gear for it to be driven backwards - the more load that is applied to the cable the more it will lock.
it works the same as a shear pin except that nothing breaks, so if it overloads it just stops, then you can back it off and set up a souble line pull or different line, so you never have to get out in the mud and replace anything.[/quote]
Thats making your drill out and use a bigger pin option the cheapest and most appealing!
Although, not having to crawl around underneath to replace anything also has its merits. Will have to look at cost involved.
Thanks for the good info people.
Cheers
Craig
Posted: Tue Sep 27, 2005 1:21 am
by wanna
ok its not the cheapest option cant remember the prices look its just a ajustable coupling you put it in place were the factory shear pin is adjust to the load you want it to slip at if it slips you only lose drive to the winch pto winchs have a worm drive so wont free spool same as when you brake a shear pin advantage is just switch line of pull or skip to double line pull and away you go again
Posted: Tue Sep 27, 2005 5:28 pm
by shorty_f0rty
apologies if this is a silly question but i just picked up a thomas pto on the weekend..
how similar are these to the toyota ptos and do they have the same thing with the shear pins?
I have it in bits at the moment but haven't seen anything that would look like a weak point for the winch (unless its in the winch unit itself) but would like to see where it is to get more familiar with replacing it (if required)...
any pointers are appreciated..
Thanks.
Posted: Tue Sep 27, 2005 5:54 pm
by CT
If its a shaft driven PTO winch it should have a shear pin located in the last Uni joint where the drive shaft attaches to the winch gearbox.
This pin breaks when the winch reaches its safe operating load to avoid damage to other components.
Carry spares and the tools (punch, hammer and multigrips) to change them.
Cheers
Craig
Posted: Tue Sep 27, 2005 8:17 pm
by frp88
how meny guys have broken the pin

mine is a tojo one 8000lbs which is about 3.6t approx. my middy only has gmv off 2.7t so if you are going up from 4mm to 6mm it will go over 10000lbs so your prob will be will your cable hold if it isnt in a good condition.
Posted: Tue Sep 27, 2005 8:55 pm
by MattGU
As i said above CT only breaks his trying to pull stumps out of his yard. No seriously to answer for him the winch was second hand and has no spares so looking for cheap easy replacement.
matt
Posted: Tue Sep 27, 2005 10:42 pm
by wanna
If you havent broken the shear pin your just not getting stuck hard enough ask anyone with a 8000 pound high or low mount or get any video with a lot of winching see em stalled all the time and cables are rated a lot higher then the winchs