Help Identify Tree Shear

[cdupuy]

This tree shear appears to be a Dymax, but I called Dymax for help and they can't identify it. The factory serial number plate is gone. The shear works fine, but I am concerned about keeping it working.

The problem with the shear is that the two pins in the center that the blades rotate on won't accept grease. I tried the basic stuff like removing the zerk fittings- they are good. The problem must be that the grease holes in the pins are clogged. I tried removing the nuts that hold the pins, I got one nut off, but the other nuts is extremely tight, or galled. The pin with nut removed would not budge after moving the shear blades around, and hammering on the top of the pin with the nut on so that I would not damage the threads.

After all that work I am thinking I really just want to get grease into the pin and sleeve joint so maybe I will try removing the zerk fittings, cleaning as much grease out of the pin that I can, and filling it with Kroll's oil to break up the hardened grease. What do you think about pressurizing the pin with Kroll's oil in it with nitrogen? Would this help move the oil through the hole into the sleeve area?

Thanks for looking at this post.

 

[J_J]

Have you tried one of these?

Grease Fitting Unblocker with High Pressure Hose

You fill it with oil and hit with a hammer.

Have someone move the blades as you pound on it.

Maybe heating and cooling the pins.

 

[cdupuy]

Yes, I tried using a zerk fitting rejuvenator. When I hammer on the rejuvenator, oil
will not go through the fitting. I have not tried moving the blade as I hammer on
the rejuvenator . I need three hands. Maybe I can get some help. Thanks for
the advice.

 

[bcp]

Shoot it clear.



Clearing grease passages using a blank cartridge

Bruce

 

[Xfaxman]

Try calling the dealer that sold it, if there are any old timers around, they would know what brand they used to sell.

Texas Bobcat Dealers: Sales, Service, Rentals, Parts for Skid Steers, Excavators and Attachments

50/50 ATF / Acetone works good on rust, might give it a try in your zerk rejuvenator.

 

[yellowdogsvc]

This tree shear appears to be a Dymax, but I called Dymax for help and they can't identify it. The factory serial number plate is gone. The shear works fine, but I am concerned about keeping it working.

The problem with the shear is that the two pins in the center that the blades rotate on won't accept grease. I tried the basic stuff like removing the zerk fittings- they are good. The problem must be that the grease holes in the pins are clogged. I tried removing the nuts that hold the pins, I got one nut off, but the other nuts is extremely tight, or galled. The pin with nut removed would not budge after moving the shear blades around, and hammering on the top of the pin with the nut on so that I would not damage the threads.

After all that work I am thinking I really just want to get grease into the pin and sleeve joint so maybe I will try removing the zerk fittings, cleaning as much grease out of the pin that I can, and filling it with Kroll's oil to break up the hardened grease. What do you think about pressurizing the pin with Kroll's oil in it with nitrogen? Would this help move the oil through the hole into the sleeve area?

Thanks for looking at this post.

View attachment 328554View attachment 328555View attachment 328556

I like PB spray oil when using the zerk fitting tool. I sometimes remove zerk, spray what I can into hole, then replace zerk and try hitting the plunger. May take several attempts.

Could be an FAE shear.

 

[SandburRanch]

Consider putting the Kroll's in the grease gun and pressuring to around 4,000#. I've unblocked a lot of force feed lubricators with just lube oil and a grease gun.

 

[stuckmotor]

Is it possible that a groove has been worn into the pins and they're hanging on the groove? I've known that to happen with a wheel on an axle.

 

[cdupuy]

I removed grease fittings, cleaned grease out of the pins ( the grease looked pretty good-no clay), I could feel the hole for the grease to move out of the pins with a bent piece of wire (impossible to clean out good because the diameter of the grease cavity is about 3/8" tops and 6" deep). Filled the grease cavity with PB blaster, and pressurized with compressed air for over an hour. No PB fluid leaked out around the pin where I should see grease. Still stopped up. I filled up the pins with PB blaster again-maybe if it sits for 3-4 days it will break up some of the grease.

I did remove two of the pins that move the blades at the front of the shear. These pins would take grease. I could beat these pins out from the bottom of the shear. My thought are that it just does not seem to be a very effective way to get grease around a pin- 3/16" hole on one side of the pin. It seems like the manufacturer should at least drill two holes, 180 degrees apart to get a lot of grease on both sides of the pin if it really needs a thorough coating of grease.

A problem with the two center pins that will not take grease is that there is a plate welded to the bottom of the pins, they will only come out from the bottom. I can only beat them out through the top, which will jack up the threads. Plus, I could only get one nut off, and I stripped some threads taking that nut off. The other nut is stuck good. Big nuts too, the nut requires a 2 1/4" socket to fit the head of the nut.

If the pins do not start flowing grease, I will have to take it to a heavy equipment shop to redo the pins. This an old shear, I don't know all of its history. Moral of the story-keep pins on all equipment flowing with grease.

thanks for looking at this post.

 

[Kycorr]

Don't know if you ever got the help you were originally looking for.....I recently had a similar quest in trying to identify a shear that was for sale on CL, but the seller didn't have a clue as to the make, model, specs....etc...
Yours looks like the one I ended up identifying as an older Hydro-Ax. They were bought and sold a couple times, and are now owned by Caterpillar. My local Cat dealer's forestry division was able to provide photos / spec sheets to make a positive I.D.