Cherry Picker Arthritis

How about: Buy a new one instead?

Don't care what you do with the old one!

It may not be rust causing the problem but that the pins have been worn out of round by the lack of grease and are now locking themselves in the bushes. You could try using the fork lift or some other available method to take the load off the boom and to jiggle it to find a loose spot where the pin can then be moved.

Once you have found that loose spot, there are a number of possibilities for getting the pin out - none of which are guaranteed to be successful, but starting with the least invasive, here are some.

1. Weld a decent sized threaded rod or long bolt to one end of the pin, slip a piece of tubing the ID of which allows for the free passage of the pin and bush, fit a decent washer over the rod and screw a nut on, tightening the nut may draw the pin out.

2. Failing this, and considering that the pins and bushes will be RS anyway, you could drill them out completely, but as they are likely case hardened that could be difficult, so you could drill a reasonably large hole right through them - case hardening won't affect the core of the pins although the ends may be a bit tough to get through, if so, heat the ends to cherry red and then let them air cool to soften them. Leave sufficient annulus of the pin after drilling to get a punch onto it, and then heat the clevis bracket and/or rod eye, whichever is causing the lock-up. When it is quite hot, you can then rapidly cool the pin by either squirting cold water through the hole or, preferably ejecting the contents of a CO2 fire extinguisher through the pin.

This may shrink it enough to enable it to be punched out, which you must do while the outers are still hot. Or you could then combine method #1 with a longer rod right through the pin to pull it out with the nut.

3. Another possibility is that once you have drilled the holes, you may be able to burn the rest of the pin out with a cutting torch (nigh on impossible to achieve without the hole), or even soften the case hardening sufficiently to then be able to drill it out.

With 2 and 3 it would be worth bracing the back end of the clevis so that you don't spread it or break it off if the pin is catching on that as it begins to move outwards.

Hope this helps.

Please be careful to do a thorough safe repair job. So many people get hurt or killed with those things.

I am concerned if you cannot even remove a difficult pin from a piston eye socket if you are qualified to work on this machine. For example: you said you applied heat to the pins already...do you think you may have damaged the O-rings or seals in the pistons which may now fail catastrophically and unexpectedly?

Those pins are 50 mm (2") and the cherry picker had a aristocrat life in a resort.

Was used perhaps 10 hours per month average. The Pins are not stainless steel and do not move one hair. Good for warning about the danger.

Things can go very bad. I changed pistons and seals on our 30 meter telescopic crane before and indeed normally pins sit loose.

The oil seals have not been too hot, I hope. If the seals fail now, there would at least be some hydraulic oil flow. Now there is only pressure building up.

He bought a new one already. And the old one was sitting next to it in the yard. Now even with a flat tire. It took A 4 ton jack and a forklift lift the base.

The compacted rubber and steel in the tire will probably be starting a new life too. It is a JCB 42' with a beautiful Deutz diesel 4 cylinder. Many people are interested

until they try the tire. It is a tubeless HD 8 ply and is gaping wide open from the rims.

I left one of world's most extended industrialized places years ago and ended up under coconut trees. Here the difficulty.

How about a Make and Model so we know what you are dealing with. A picture will do. If the new hose was spec out properly it should have never burst. Should be able to handle the highest output pressure that the pump is rated for. If you are trying to lift the cage with some external equipment like a forklift. You may have to remove the hydraulic hoses. Oil in the lift cylinders will not allow any movement if there is no where for the oil to go being held by the control valves. Also after the valve replacement are you sure the hoses are back on properly? That they are wired properly? Since I can not see the state of damage before replacement. It maybe the damage was great enough that a clear state of assembley was not there. And best quess was wrong.

Well, if it were me with limited resources. I would douse the pins with Coca-Cola, ideally submerged overnight.

Then rig up a fixture of some kind and use a porta-power to press them out...or pop them out, pun intended.

Your saying this is JCB 42', is this a loadall telehandler forklift or is this an actual telescopic boom man lift? One of the main faults for blowing hydraulic hoses is a failed pressure relief valve. The relief valve should prevent system pressure to exceed working pressure of properly rated hoses.

As stated before, this equipment can and will kill you! I had to deal with the aftermath of an idiot who removed the PR valve from a scissor man lift while it was elevated and not support.

Now, which pins are you trying to remove? The boom assembly has to be supported in a neutral position, with no load on the actuators and the actuators slide back and forth on the pins. Otherwise your wasting your time.

As far as the make up of the pins themselves, ours were cr steel with the retaining plate welded on them and not case hardened.

boom man lift.

Has a short section to lift everything up and that works.

Sliding in and out works also

Positioning the cage works also

1 or 2 pins that do the boom lifting (long part) are blocked.

I have braced the whole system with wooden jacks, so that is is resting on it.

The relief valve does not affect the position because of the blockage of the pin/cylinder/bushings

The pins are rusted in the bushings (all steel) and now also the cylinder heads.

When trying to operate this function, the engine almost stalls just before the overpressure valve opens. (before the hose explodes)

I have been thinking of cutting the piston and pads out, fix or replace and welding the set back together.

I can use a forklift to re- position it.

Thank you. D

It would come as a startling surprise were it to pass its insurance examination unscathed.

So scrap it and buy a replacement that will pass its insurance exam.

These machines are not even insured here since they are for private use. Use at own risk.

It is like the private ladder in your shack, only it sits outside in all weather conditions.

Ask JCB. Their customer services department is probably the most helpful that I have ever encountered.

try one of these... OTC Porta-power

We use one to remove frozen pins on our loaders etc.(works most of the time

Well, you have lots of suggestions on your mechanical difficulty, but if you have blown 2 hoses(same circuit I am guessing), get to the root of that. Two possibilities I can see:

1 - the hoses you used are not rated for the design pressure in the circuit and,,,

2 - more than likely, if indeed the hydraulic circuit has one, you have a stuck or malfunctioning relief valve causing overpressure in the circuit.

If indeed the maintenance is lacking in the basics, probably no thought has been put into the hydraulic maintenance either. Circuit should have some filter(s) in it some where, at a minimum a suction screen and a return filter(which likely has a bypass so you can't readily see if it is really in use)

I tried explain the PR valve in my #7 post. I used to work QA with UpRight manufacturing man lifts and telehandlers. It can get deadly if something goes wrong, so I am reluctant to keep feeding ammo to someone playing Russian Roulette. I just hope he can fix this thing safely with no one getting hurt.