Cat 225 won't budge.

[JimBowatBeth]

We have a 225, s/n 76u05834, that's been sitting for a few years...

Changed the fluids, filters, new fuel, greased everything we could get to, but can't get it to crawl. Niether track wants to move, even when elevated off the ground.
I know that there is a spring/hydo brake system in there - somewheres..

The last time it was moves was bout 7-8 years ago, by a long since retired operator. Now, it's in the way, and can't go.

My question - How, and were can I test for the hydo pressure to release the breaks? Or is there something else that I'm missing? (I'm blind in one eye, and can't see out of the other )

Jim

 

[Bob/Ont]

Does the engine load down when you try to travel?
Later Bob

 

[Nige]

Also can you see any signs that there is pressure in the hydraulic hoses to the travel motors when you try to move the machine..? They should go like iron bars.

 

[JimBowatBeth]

Yes, it does.

Jim

 

[JimBowatBeth]

I havn't been able to get any of the covers off yet.. I'm down there with a digging bar and sledge hammer to get to cement-like junk off of the running gear. It doesn't help with the rain we had last night making everything a slippery, sloppy mess.

The engine does bog down when I try either direction.

 

[Nige]

Jim, the travel motor brake on the 225 is sandwiched in between the motor and the final drive. You will need to get the protective guards off first in order to see anything.

If you check out the two smaller diameter hoses that go to the area of each travel motor you will find that one of them connects to the body of the travel motor itself (that's the motor case drain line), the other connects to a housing closer to the final drive housing. That's the line that carries the pressure to release the travel brake. The brake itself is a series of discs and plates that is applied by a set of springs and released by oil pressure. Possibly after having been standing for so long that discs and plates could be seized together so that even if the oil pressure is reaching the brake release piston the output side still won't move.

 

[mitch504]

A long shot or dumb question: You do know how the track controls work on a 2xx Cat, don't you? One pedal at a time, for forward or reverse, steer with the stick. If you have one track off the ground, you have to push the stick halfway to decouple it from the other track.

Not trying to be insulting, but I still mess w/ these old girls a good bit, and have seen some good operators of everything else not be able to make them move. You should feel it try, so this doesn't sound like your problem.

 

[Nige]

A long shot or dumb question: You do know how the track controls work on a 2xx Cat, don't you? One pedal at a time, for forward or reverse, steer with the stick. If you have one track off the ground, you have to push the stick halfway to decouple it from the other track.

Not trying to be insulting, but I still mess w/ these old girls a good bit, and have seen some good operators of everything else not be able to make them move. You should feel it try, so this doesn't sound like your problem.

I second that it's worth a try. Right pedal is for forward travel on both tracks, left pedal is for reverse ditto. The steering lever simply controls how fast one track moves with respect to the other.

 

[Bob/Ont]

If all else fails and you only need it moved the final drive pinion can be disengaged and machine towed CAREFULY. In that condition it rolls freely and you have no control over that.
Later Bob

 

[JimBowatBeth]

Thanks for the tips so far guys.

Took all morning, and half the afternoon, but I FINALLY got to see the top 1/2 of the motors, the bottom is still buried in frozen mud. :Banghead


Nige - I took the line off both motors - even though I could see where they T off of. No dice. Not a drop of fluid on either line when trying to move

Mitch - Very good point! I read somewhere that one was for forward and the other was reverse, and the stick was direction. If I had another of our "operators" try to move it, they probably just jam on both at once like on the mini...

Bob - Unfortunately, I don't think I want to do that just yet - maybe a "option-z" It's sitting cross-ways on a hill side with a birm pushed around it. And, after Sandy, too may tangled/fallen trees around.

Anyways, how does the breaks get their fluid/pressure from? Some how from the traction pedals? Or is there an electric solenoid that supply's pressure?


Thanks again for the help,

Jim

 

[Nige]

Jim, do the 2 large hydraulic hoses to each of the travel motors show any signs of pressure in them when you try to travel..? At the very least you should see them twitch when you press either one of the travel pedals.

AFAIK without referring to the SysOp the brakes are released by implement system pilot pressure but I am not 100% certain of that. Maybe Bob/Ont can confirm.

 

[Bob/Ont]

Yes it's pilot pressure . Follow the smallest hose from the top of the swivel up and you will find the brake release valve. The brake release valve will keep them locked on if you manually turn in the screw with a square end of if the pilot pressure is low, forget how low. Check that out first. Resolved pressure from for/rev R/L will get to the valve to open it.
Later Bob

 

[Bob/Ont]

caution if you boost the brakes don't use more than 365 psi.
Later Bob

 

[JimBowatBeth]

Nige - I couldn't see them clearly from the cab. I'll have a assistant with me later this morning.

Bob - I'll go hunting for the vale later this morning when I get some light. 365psi seem, atleast to me, low pressure, I was thinking it would be around a 1,000.

Thanks again

Jim

 

[Nige]

Jim, pilot pressure on the machine isn't going to be that high. It's usually around 350psi but if Bob says 365 I'd go with his recommendations.

 

[Bob/Ont]

I meant 365 as a MAX, too much can blow things apart.
Later Bob

 

[mikebramel]

365PSI isn't that much but when you consider the surface area of the brake piston that is some good force

 

[Shimmy1]

How hard is it to pull back the travel motor? On our old 1080B, there was a toggle switch to manually turn the brakes on and off. If you were in low range and forgot the brakes on, if you moved it more than a few feet the brakes linings would stick themselves together. Didn't take long to fix, pull covers, couple bolts holding drive motor, couple more to pull cover off brake housing.

 

[Nige]

How hard is it to pull back the travel motor?

pretty difficult if you read the OP's posts on Page 1. It sounds like the travel motors are buried in mud that's packed like concrete. Even if you removed the motor on that particular model I don't think the brakes would come off because the brake pack is not built into the motor like in modern excavators, instead it's separate and sandwiched between the motor and the final drive. The motor output shaft drives into the brake pack, a separate output shaft connect the brake pack to the final drive, in fact I think it's referred to as the final drive input shaft.

 

[Bob/Ont]

A smart man would connect the brake hose to a manual pump with a gauge and release them if they will not come off by normal operation. The brake release valve allows for a manual lock up for testing and also prevents the brakes being partially released with low pilot pressure. I seem to think the magic number is around 270 PSI. Someone with the system operation on any 200 series exc can find the exact number.
Later Bob