Help .... Frozen hydraulic pivot pin

[Big Barn]

An exothermic lance will do it.

 

[Navvet]

OK I get it. As long as you can get the cap end free, could you rebuild the cylinder without removing the rod end from the machine?

No, I have a guy that rebuilds cylinders for me. That's one thing I leave to the pro's.

 

[LouNY]

How about drilling the pin start as close to center with a small bit,
drill in a couple of inches, then just start up sizing drill bits.
If need be go up to an 1 inch then try to drive it out.
Keep soaking it with penetrating oil while drilling the vibrations and time are likely to loosen it.

 

[Williy]

I could not see if the jack had a small bolt
or piece of metal the same size as the pin
I would have applied pressure this way and
applied wd40 or what ever and then hit it with
a 10 lb sledge hammer a few times its more
than likely to be rusted very hard to remove

willy

 

[ohiogar]

Seen a couple stuck pins in my day...
On your hydraulic press jig there which looks really nice by the way...
Most all hydraulic cylinders have from a little to a lot of side to side clearance
on the shaft. if you take out all of that clearance then put as much pressure on the
pin that you are comfortble with then with one really good hard smack with a 12 pound
sledge it should break it loose. Take as much time as needed to get into the perfect position to swing.
It is a whole lot of preparation for one hit but it is worth it.
It would be much better if you could
do it without the hydraulic which is gonna cushion some...A thick steel plate against a concrete wall
or similar with a piece of thick walled pipe barely larger than the pin tacked onto it then find the biggest guy you know that hand splits wood to do the swinging.
Also take into account what may or may not sproing when it gives that tiny little bit with that much pressure on it.
gary in ohio
Happy New Year All

 

[ROUSTABOUT]

If you got movement it should come out. Last one I did was on a hydro axe. A pin had fell out on the bottom. He cut a large tree and was driving with it to lay it down. Rode over a stump and when it shifted it snapped top of boom off. They had worked on it a week or so before calling me.

 

[Tony H]

I cannot believe the bracket and Jack didn't do it. Drilling your way up until the last bit will collapse sounds good. Welding something on the end so you can try to rotate it might help.

 

[Garson]

Popular Science Magazine did a review on penetrating oils a couple of decades ago. Since they I have used their winning choice successfully many times. Make a 50/50 mix of Acetone and Automatic Transmission Fluid. Shake the mixture in a squeeze bottle and apply immediately after shaking, before the acetone comes out of suspension. It's magic.

 

[RancherGuy]

Popular Science Magazine did a review on penetrating oils a couple of decades ago. Since they I have used their winning choice successfully many times. Make a 50/50 mix of Acetone and Automatic Transmission Fluid. Shake the mixture in a squeeze bottle and apply immediately after shaking, before the acetone comes out of suspension. It's magic.

'decades ago' might be considered old news. There are new products. Suggest checking out some reviews such as

 

[RancherGuy]

'decades ago' might be considered old news. There are new products.

Then there is review #2:

 

[MinnesotaEric]

Penetrating oils don't really work until the stuck bit starts to move, then they start to work. Alternatively, you can try heating and then hit it with oil to try to draw the oil in to loosen then stuck bits.

If my heat it up and hit it with the biggest air hammer you get your mits on doesn't strike your fancy and neither does lancing it out, then you can try heating, and rapid cooling with a hose over and over until the thing cracks loose as you would with the stuck exhaust header bolt.

 

[RancherGuy]

Penetrating oils don't really work until the stuck bit starts to move, then they start to work. Alternatively, you can try heating and then hit it with oil to try to draw the oil in to loosen then stuck bits.

If my heat it up and hit it with the biggest air hammer you get your mits on doesn't strike your fancy and neither does lancing it out, then you can try heating, and rapid cooling with a hose over and over until the thing cracks loose as you would with the stuck exhaust header bolt.

They work for me. I had a 1950 Ford tractor that sat out in the humid weather for decades. It had a locked up transmission and I bought it that way. I wanted to give my father the front axle, so I put penetrant on all lug nuts - front and rear. A day later, added a little more. A day after that, more. On day 4, I put a socket wrench to them and they all acted like they were installed the week prior. If there is movement, my experience is that there is faster action, but even without movement there is success because it penetrates just like the water that entered in the first place. Like you say, sometimes the approach used requires consideration of available time.

 

[JPRambo]

This stuff if you can find it, is amazing. As said earlier a couple squirts in morning and again at night. A couple days and it's free. Not as cheap as WD-40 but works tons better.

 

[metalbender]

The exothermic lance will do it in minutes, what's the hold-up?

 

[Big Barn]

The exothermic lance will do it in minutes, what's the hold-up?

Thank you....

 

[efox]

Retired oilfield machine shop welder kicking in my 3.5¢. Some good ideas here and as I’ve done this kinda thing daily for years I’ve found out nothing works on everything every time. My attack procedure became to try the simplest thing that likely would work and move up in difficulty and time demand as needed. Most, if not all these suggestions have their time and circumstance.
I would avoid for now the oxy or air lance on that small pin since it is unlikely that you can gouge through without gouging the frame bosses-or cylinder sleeves. If you do that you may as well have cut them out with a torch and replaced them. The saws all is a good idea but it may take some time to cut through and then you’ll still have to press the pin parts out.
IMHO the best shot is with the mag drill. It’s hard to make a solid pin or shaft shrink if it doesn’t have a space to shrink into. What usually binds, if the pin isn’t doglegged, is the boss or sleeve in the rect tube beam being pushed elliptical by the flex in the beam. If you can’t block that solidly very close to the bore, the press is actually jamming the pin in tighter. In a 1.5 dia. pin that center hole will be best if bored at least 3/4”. Any bigger will help but the goal is to provide a space for the pin to contract into.
Step 2: heat the pin from the inside bore. The idea is to expand the pin and compress the rust or scale tightening the fit, then to allow the pin to cool and shrink into the annular bore. You need not do that with a welder. It does tend to quick heat and self quench but if you fill the hole with weld metal you may not gain as much shrinkage as if it were left open. Differing opinions but I’m my experience you are better off not to quench. It may crystallize and cause the pin to break when pressed. Time is on your side and there is no real hurry to cool it down. Anything below 300° and you can cool with water or oil and finish the shrinkage. Better to pull than push the pin but unless you have a hollow center ram and are real good at welding a pull rod on that is probably out.
Now for the real radically, extreme suggestion: rebuild the cylinder in place. Remove the packing gland/nut while the cyl base is attached, remove the cyl from rod and piston, remove piston and packing nut from the rod end, rebuild and replace.

 

[CADplans]

When the pin is distorted, or galled on the end,, force is almost impossible as a method to move the pin.
The distortion or galling is actually increasing the diameter of the pin,,
Pressing, or hammering must then distort the mating part to get the pin to move.

Oils do not help when the issue is an interference fit,, a pin that is galled on the end is an interference fit.
Pressing, or hammering, beyond a reasonable amount,, only insures the mating part will also be destroyed.

This is not a threaded joint, it is a pin, in a hole.

Threads respond to penetrating oils,, pins,, not so much,,

Cut the pin, save the mating parts. the pin is the low cost item to replace.

 

[wdchyd]

Navvet, after you get it out have your hyd shop cut at piece of hyd rod stock for a pin. It’s made from 1045 medium carbon stock and will work nicely. You might get lucky and he has a chunk in the scrap bin.