Stuck Pin? Hydralics Question

[timcote42]

Greetings all. I just bought a B7100 with a backhoe and a loader attachment, knowing full well that the swing cylindars on the backhoe were leaking an needed servicing. So today I did a bit of Thanksging tinkering and attempted to pull them out, but ran into a snag. Let me say up front that this is my first tractor, and while I once rebuilt a kubota engine (came out of my sailboat), I have no experience with hydralics.

Anyways, in trying to pull out the swing cylindars it seemed obvious that I should remove the pin that secures it at the proximal end (the part nearest to the operator). As shown in the photos, the pin was held by cotter pins above and below. I removed these cotter pins and was very surprised to find the pin totally immovable, on both sides no less! Stuck a screwdriver in the pin and couldn't rotate it, tried to lightly hammer it down, wouldn't budge, put a pipe wrench on the part sticking up from above and it wouldn't go.

I put in some WD40, took these pictures and saved the heavy ammo for response from this group. Assuming the WD40 doesn't miraculously loosen the pin, my next efforts would include using a gear puller or heat from a torch to bust the thing through. Given that both plates of the bracket with the holes through which the pin passes are welded to the rest of the hoe, it seems this pin MUST be extracted. Any advice before I get mean with this thing?

Tim

 

[Birdhunter1]

Is there pressure against the cylinder?
If there is it willprobably not move without ALOT of force and then will still be a booger to get out. Since it is off the tractor to get the pressure off the cylinder I would crack loose the hydraulic hoses and try to pry the cylinder back and forth a bit to relieve the pressure and the pin will probably fall out easily.
I would steer clear of using heat as pressure can build up in the cylinder and cause it to explode.

 

[MrJimi]

I am NO hydraulic expert by far but if you have any weight or pressure on this fitting. It will not come out
Jim

 

[charlz]

I have the same tractor and hoe... matter of fact from the missing paint and oil all over the place I had to look outside and make sure mine was still there

My swing cylinders also need to be repacked. When I looked at pulling the cylinders I was thinking it might be easier with it still mounted on the tractor. I am thinking your main 'swing pin' is worn and with the weight of the hoe resting on the boom your are getting some of that on the swing cylinder pins causing them to bind. If it was still on the tractor you might be able to use the boom or bucket to move up and down and find a 'sweet spot' where the pins will nearly fall out.

Try pushing down/lifting the end where it bolts to the loader and see if it makes any difference.

If you do have to drive the pins out it might be very difficult to get them back in.

Charles

 

[638]

If everything else fails, grind or cut off top end of the pin flush with the top bracket. Center punch and then drill into the end of the pin with increasing sizes of drill bits at least 1/4 the way through the pin. If the pin is 3/4" , you will want about a 1/2" hole, centered. Insert a short punch or maybe a 7/16" bolt in the hole just drilled. Use a heavy hammer and smack the c**p out of it. You may need to support the lower bracket to keep it from bending. The one thing that you don't want to do is mushroom out the end of the pin. Shoot some grease into that zerk fitting also.

ron

 

[TalonDancer]

You haven't said whether the swing cylinders on this BH actually work at all. Specifically, when the BH is attached to the tractor...

* do the swing cylinders swing the BH --- over the full range?
* do the pins rotate with the cylinder ends?
* do the cylinder ends rotate and the pins hold still?

IOW are the pins stuck in the cylinder bores, the frame or both.

FWIW if I were trying to free up a cylinder/pin I'd try to use the force of the tractor's hydraulics to do as much as possible before resorting to hammers, drills, pipe wrenches, etc. I don't see any grease in your pictures. Like 638 says, there's a zerk on that puppy -- use it If nothing else you'll find out if and where the grease comes out.

Talon Dancer

 

[timcote42]

Thank you all...what rapid service...only about 5 hours after posting and 5 messages. My wife say y'all are loosers and me too for being on the computer on Thanksgiving eve. But I am grateful, and that's what the day's about...

Okay, well I think the best advice is that it's likely bound up, and unwilling to move until I get the load off it. Indeed, the boom is off the ground. Yes, the swing cylindars did operate before I took it off the tractor, full left, full right, puddle of oil on the ground.

My next efforts will involve tipping the hoe on its side and trying to release the tenstion which no doubt is on the pin(s). Fortunately, I have a tractor to make pushing the metal around much easier. Would like to avoid the drilling the pin bit, but will if all else fails.

Tim

 

[TalonDancer]

...
My next efforts will involve tipping the hoe on its side and trying to release the tenstion which no doubt is on the pin(s). Fortunately, I have a tractor to make pushing the metal around much easier. Would like to avoid the drilling the pin bit, but will if all else fails....

From one looser to another

DON'T tip the hoe over! Hook it back up to the tractor. When the boom is pinned up (on level ground) there should be 0 force on the swing pins. They just rotate the hoe about the boom base axis. This position gives you the most leverage you will ever get at rotating the pins in the frame/cylinder bores. And it gives you the greastest ability to relieve any binding pressure on these pins. Yes even if you don't hook up the hydraulics.

FWIW I'd remove the other end first. Once they are off. You can manually center the boom and pin it straight. Then remove the hoe and get to the "proximal end".

Talon Dancer

 

[SPYDERLK]

Perhaps there is trapped pressure in the hyd lines and the two cylinders are pushing equally against one another. Tap the plug poppets and twiddle the levers. Repeat until no oil gushes out of the poppets.
larry

 

[LazyBoy]

When it's moved does the cylinder move on the pin or does the pin move? if the pin moves then the pin may be rusted into the cylinder, that could be very hard to get out. If it was mine I would start with some good penetrate like PB blaster and then put some kind of SOLID support under the lower cylinder support and that solid I-Beam like a adjustable screw jack or solid oak and then smack the **** out of it, it should move if you have solid support under it. You may want to try unhooking the other end first also.