I am trying to replace the lower arms on my L3710 and it looks like the pin holding the arms in terminates in the brake case. The pins are very rusted and won't budge. Please help?
With the bolt out, try welding a lever to the end of the pin. After it cools use some PB Blaster and some heat on the iron around the pin. If it won't lossen, may need to take off the brake housing and drive it out from the inside?
That's what I was afraid of about removing the brake housing but not sure what would be available inside there? I also was told to try to heat up the pin and then let it cool and use an air hammer?
Yep. Kubota dealer confirmed its a blind hole and does not extend into brake case. Said they would probably have to cut it off with a torch and then burn the remainder of pin out of blind hole in brake case. I tried some heat not red hot and nothing. Tried Freeze Off penetrator and nothing. Been soaking with pb blaster for 3 days and not budging. It appears the ball is froze onto the pin, cause the arm moves freely, is wallowed out and the ball does not move. I'm stumped?
Will the ball slide side to side on the pin at all, if not try heating the ball a bit and then tapping on the arm to get the ball to slide. Once you get it loose then you can work on getting the pin free, take the bolt out and try tapping on the pin ear and see if you can get it to rotate in the bore, if so it should start to loosen up. Just go slow and easy so you don't take a chance on breaking the case.
Yep. Kubota dealer confirmed its a blind hole and does not extend into brake case. Said they would probably have to cut it off with a torch and then burn the remainder of pin out of blind hole in brake case........
Have they done this successfully before? I'd exhaust the possibilities of welding on a lever or pull-pin before letting anybody try cutting it out with a torch. It takes good skill to melt a steel pin out of a cast iron hole without damaging the hole. Cast iron melts around 2000F but steel is around 2500F. Just saying.
Do you really need to take off the arm? If the looseness is the issue, get someone to reduce the "wallowed out" clearance by adding some weld metal to the arm. It won't be elegant but it will be strong.
The factory pin has an ear with a hole that allows the pin to be secured to the case with that bolt shown in your photos, as bumpkin says. The pin itself is not threaded and simply slides into the two holes. It looks to me from your pictures as if the ear is no longer on the pin or the original was lost and a simple straight pin was used to replace it. If that's true, there may be more than just corrosion holding it in place; someone may have welded the thing. Here are the part numbers for the pins and that bolt, if and when you can get the old ones out of there:
Lower link pin: TA040-39412
SEMS Bolt: 01133-5120
Looks like that 3710 has had some hard use. Good luck with your repairs.
If arms must have to come off. Then put a good tack weld on the arm and ball. Remove the bolt that is holding pin in, move arm up and down to make sure pin is loose. Then put bolt back in then move the arm up and down to get ball loose from pin. If you put some weight on the 3pt then you could use the hyds to do the work.