How do I grip hydraulic piston to unscrew end?

[Cold Camel]

My backhoe was profesionally shop built but needs adjustment. In travel mode the bucket is too far from the 3pt. If I can screw/unscrew the ends a few turns, I can tuck the boom and dipper. Strength isn't a problem because it's a 3pt backhoe so I have to dig gently.

My question: how do I grab the piston? I don't want to pull the cylinder and stick it in my vice because the adjustment will be somewhat precise. Nor do I want to bugger the threads or piston. The lock Allen screw is loose, but my duct-tape/pipewrench and Vice-grip/rubber combos slipped. There might be a bit of paint I'll need to torque through. I could bugger the last inch of threads, but that is not elegant. I figure I have the tools and one of you has the brains.

A picture is worth lots of words. We'll see if I can do it.

Cold Camel
YM1110D

 

[Grut]

If you can, clean up the threads. My want to try a small rubber strap wrench on the cylinder.

 

[ragkar]

I don't know if this will help, but many years ago in high school shop class one of the guys wanted to grip the polished surface of his class project with vice grips. But that would leave tooth marks!
The teacher's answer was to wrap copper flashing (thin sheet) around the item and grip that.

 

[Willl]

If I can screw/unscrew the ends a few turns, I can tuck the boom and dipper.

Are you trying to adjust the length of travel by how far the 'cap' is turned on ?

 

[magicheater]

I don't know if this will help, but many years ago in high school shop class one of the guys wanted to grip the polished surface of his class project with vice grips. But that would leave tooth marks!
The teacher's answer was to wrap copper flashing (thin sheet) around the item and grip that.

I have done the same with aluminum sheeting, seems to work, used some some when straightening a cylinder in a press. No marks.

 

[Cold Camel]

Great help, now I'll look for metal sheeting. I've had both but don't know if I have either on hand.

The paint is not worth scrubbing unless it binds after I crack it loose.

Travel length is what it is. I want the parts to tuck more, even if I lose full extension, or depth capacity. The tractor felt much better with 150# in the loader but this tractor is tiny, <800# bare, so I would rather fix the balance.

Spot on answers, guys. No photo necessary. I still have light, so I'm back outside.

Cold Camel

 

[IceStationZebra]

There are strap wrenches made for this type of work.

And if worse comes to worse you can:
- unhook the rod end
- fully extend the cylinder
- turn the clevis while somebody else holds the valve at relief
(just be careful)

ISZ

 

[Cold Camel]

Mission Accomplished.

Didn't have thin metal so I wrapped threads with SS wire in line with threads, clamped on the vice-grip, and twisted a pipe through pin holes. Voilà! Thread rust couldn't resist. Plenty of PBB and it turned by hand. No need for the zebra option, nice to know though. Wire was not optimal.

End result ... Bucket tucks 10" closer to boom (adjusted boom and dipper), just as I hoped.

Thanks to all ... Close this thread ... Go help someone else....

Cold Camel

 

[jbooth]

Glad you solved your problem. Will post a method similiar to your wire method.
In an old gunsmithing book, I found a rope wrench for removing barrels. Double the rope making an eye, make numerous wraps around the barrel, place a cheater through the rope eye, and twist until all the slack/streth is out of the rope. I believe this method would work better on a hydraulic cylinder than a rifle barrel due to size. Notice there are a lot of lookers in addition to posters on these threads so hope this helps someone in the future.

PS the book called for a pick handle for the cheater, but I imagine pick handles might be hard to locate.

 

[maybar]

Glad you solved your problem. Will post a method similiar to your wire method.
In an old gunsmithing book, I found a rope wrench for removing barrels. Double the rope making an eye, make numerous wraps around the barrel, place a cheater through the rope eye, and twist until all the slack/streth is out of the rope. I believe this method would work better on a hydraulic cylinder than a rifle barrel due to size. Notice there are a lot of lookers in addition to posters on these threads so hope this helps someone in the future.

PS the book called for a pick handle for the cheater, but I imagine pick handles might be hard to locate.

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Something better than a rope is two ropes 180° apart. This method gives better in line torque rather than so much side ways prying force. Examples: A thread tap is more likely to be successful using a T handle as opposed to a single handle and Easy-Outs are less likely to break using two wrenches as opposed to one.

And something I've found mighty handy is rubberized shelf liner gripper available at most Marts.