Offroad-Express

Been yarning to a few people about sheer pins etc and at the moment running a roll pin in a 4.5 mill hole but I'm paranoid that its going to break when I'm balls deep in a mud whole and can't climb under the veichal,
I've hurd six mil bolts do the trick but is the winch rope going to be the week point or the drive shaft and ujs going to give up first, i do sum times use a block to dubble back to make it easier, and wat is the lb rating of the winch

something always has to be the weak link.the shear pin is the cheapest thing to break although can be a right pain in the ass.what you could do is slide another rollpin down the inside of the oneyour using ow to strengthen it up a little.just make sure the slots are 180 degrees out fromeach other.

I have been there done that with mine and settled on a 6mm grade 8.8 bolt.
Avoid using roll pins as you need a punch to get them out....
Where as a bolt will generally drop the head and tail off.
You line it up and use the new bolt to push out the bit stuck in the center...
If it also doesn't fall out...Put on a nut and off you go....

if its a toyota pto you've got the problem that there isnt enough meat on the coupling to drill it out much more than the standard 4mm or you'll turn the coupling into the weak point instead of the shear pin. You need to start modifying shit if you want to stick a bigger shear pin in there

What I found is the coupler to shaft is to loose, I got a better one made, it is a tight push fit on the shaft. not busted another one since. Was going through them at regular intervals. Am using the standard size hole with a cap screw and nut. seems to work well for me.

mudmike wrote:What I found is the coupler to shaft is to loose, I got a better one made, it is a tight push fit on the shaft. not busted another one since. Was going through them at regular intervals. Am using the standard size hole with a cap screw and nut. seems to work well for me.

Yep that is key, if you have slop in the shaft you get enough movement to increase the strain on the shear pin,
reducing its capacity. I had mine totally rebuilt and made a huge difference, also used cap screws and never broke another one.

Previously had been using 4" nails with the slop and its surprising what you can pull on them, got my self out of a fair bit of trouble, but broke heaps of them too, lying in the mud replacing them isn't fun.

Do make sure you keep the shear pin the weakest point tho - I'd rather do a pin than a smashed drive.

Have put a 5mm high tensile cap screw in mine so it won't break there and then put a shear flange with a 8mm mild steel shear bolt in it further along the shaft so that you can get at it when your balls deep in do do. I break my 10mm plasma before the shear bolt. Plasma is easier to fix.

jj1959 wrote:Have put a 5mm high tensile cap screw in mine so it won't break there and then put a shear flange with a 8mm mild steel shear bolt in it further along the shaft so that you can get at it when your balls deep in do do. I break my 10mm plasma before the shear bolt. Plasma is easier to fix.

Do you really want to break a rope halfway up a bank only to fall back at great speed???? Not an issue if you are just pulling thru bogs....
I would rather shear a pin at least you stay in one spot......

Most of the time 10mm is ok. Only tends to break on those steep uphill deep mud climbs where you get pulled in to bank. Winch usually complains a bit before that happens. Then you stop and change to double purchase. If your on such a steep bank that your going to come plunging backwards if the rope breaks you probably should be on double purchase anyway. Bronze bevel gear in toyota winch is a bit soft and starts overheating badly even with a good quality bronze gear oil. Hate changing shear pins even when they are easy to get at like mine is.

jj1959 wrote: Only tends to break on those steep uphill deep mud climbs where you get pulled in to bank

dont want to take your post out of context or anything but when a winch cable breaks can sometimes be predictable (usually when you know your overloading it) but the rest of the time it can be very unpredictable and break when your not expecting it

yea mine brok in a week point so wasn't under full load and i almost shat my self, went with a massive bang, showed how good the dampener things work luckily

Sadam_Husain wrote:

jj1959 wrote: Only tends to break on those steep uphill deep mud climbs where you get pulled in to bank

dont want to take your post out of context or anything but when a winch cable breaks can sometimes be predictable (usually when you know your overloading it) but the rest of the time it can be very unpredictable and break when your not expecting it

Absolutely. And a shear pin ain't going to fix that. It would be nice to predict the unpredictable.