Case IH 585 brakes

[Km722]

I have a case IH tractor with a brake issue. I have replaced the revisor tank, the master cylinders, and I have even replaced the o rings in the axle housings. I’m still having issues with the brakes bleeding off after a couple days. The problem is that resivor tank will drain after a day or so. I have pressure tested the axle housings with air and let sit for a couple days wondering if I had pinched an o ring and only loose a couple psi. I am stumped and was wondering if anyone has had a similar issue. Thanks

 

[used red MN]

I have a case IH tractor with a brake issue. I have replaced the revisor tank, the master cylinders, and I have even replaced the o rings in the axle housings. I’m still having issues with the brakes bleeding off after a couple days. The problem is that resivor tank will drain after a day or so. I have pressure tested the axle housings with air and let sit for a couple days wondering if I had pinched an o ring and only loose a couple psi. I am stumped and was wondering if anyone has had a similar issue. Thanks

Hello Km722, welcome to YT! What does your air test setup look like and how much pressure are you putting on it? Obviously air compresses, depending on how much air volume you have compressed against the oil you could lose a couple of ounces of fluid and only drop a couple of psi. You may need to setup something like a 6” section of 3/4 inch pipe that can be held vertical. Fill within an inch of full with fluid and pressure on top of the fluid. Put your block valve and gauge down stream of that so you are testing how well it holds with fluid alone. One would think that if the orings were leaking in the axle housings the pedal would drop when the brakes are held applied.
I know there have been one or two threads on here about the design of brakes on some of these similar tractors. They have a small stream of hydraulic fluid flowing into a reservoir that feeds the master cylinders. Then a standpipe in the reservoir maintains a level that drains back to the case. The problem was that the standpipe was poorly secured and would slide down lowering the fluid level. I have no idea if that for certain applies to your model.
Here is a link to the CNHI manufacturers parts catalog CNHI CaseIH 585 brake diagram That is the “without cab” cab diagram, if you arrow 3 to the right that is the cab tractor diagram. I don’t see a standpipe shown. The point is there is no cap shown to fill it. Hose 7 says it is the fluid supply so it must have some type of system that maintains a level in there.

 

[Rbellucci]

Dealing with the same thing on a 585 before. If there are no external leaks, check the boot on the master cylinders again. Sometimes they can leak into the cab or down the frame where you won't notice it immediately.

 

[Km722]

Here’s are some pictures of the old tank vs the new tank setup. Also put a picture of my gauge setup I used. I put the gauge where the feed line goes into the master cylinder and pressurized the whole circuit.

 

[used red MN]

Also put a picture of my gauge setup I used. I put the gauge where the feed line goes into the master cylinder and pressurized the whole circuit.

At what pressure? Just the compressed air in the short line between the valve, tee and gauge could allow some leak off without a substantial pressure drop. I have no idea what your brake problem is or if this will detect your problem, but pressurizing the test circuit with all liquid is the most sure way to get an accurate result.

 

[Km722]

I’m pressurizing to 100psi. How would you recommend pressurizing with liquid?

 

[JimB2]

Hi did you replace all 3 O-rings or only 2 of the 3?

 

[Km722]

I replaced all 3. 3 on each side.

 

[MARK ROBKE]

I have a case IH tractor with a brake issue. I have replaced the revisor tank, the master cylinders, and I have even replaced the o rings in the axle housings. I’m still having issues with the brakes bleeding off after a couple days. The problem is that resivor tank will drain after a day or so. I have pressure tested the axle housings with air and let sit for a couple days wondering if I had pinched an o ring and only loose a couple psi. I am stumped and was wondering if anyone has had a similar issue. Thanks

I have replaced several of those brake piston o rings in the axle. Did you replace all 3 o rings on both sides? It's been about 7 years since then, and I can't quite remember visually how it goes together. I do remember pressurizing the piston with air, but sometimes it held air but would still leak fluid off. Bleed them and they were ok for a few days- in other words the air test was not always accurate. Usually new o rings did the trick. Not too much trouble with the master cylinders. Mark. PS. Sorry Jim posted while I was typing.

 

[used red MN]

I’m pressurizing to 100psi. How would you recommend pressurizing with liquid?

Per my info in reply 2.

You may need to setup something like a 6” section of 3/4 inch pipe that can be held vertical. Fill within an inch of full with fluid and pressure on top of the fluid. Put your block valve and gauge down stream of that so you are testing how well it holds with fluid alone.

Of course you would need the proper fittings to adapt the ends to the 3/4" pipe. The pipe held vertical will be your test fluid supply reservoir. Your gauge and valve will be connected to the bottom of it. Put in the fluid pressurize the pipe, close the valve and see if it holds.

 

[JimB2]

I replaced all 3. 3 on each side.

Good, when my brother and I did his CIH 3230 we damaged the one on the left rear diff bearing carrier on the bottom side and had to replace it.
Luckily we noticed it before reassembly.

 

[Km722]

I have replaced several of those brake piston o rings in the axle. Did you replace all 3 o rings on both sides? It's been about 7 years since then, and I can't quite remember visually how it goes together. I do remember pressurizing the piston with air, but sometimes it held air but would still leak fluid off. Bleed them and they were ok for a few days- in other words the air test was not always accurate. Usually new o rings did the trick. Not too much trouble with the master cylinders. Mark. PS. Sorry Jim posted while I was typing.

Yes I have replaced all 6 o rings. That was the first thing I did. Then I replaced the master cylinders. When I replaced the master cylinders I noticed the stand pipe was fell down in the return line. I ended up just replacing the tank. Still having the same issue as before though. The tractor will bleed fine and have stein brake pressure. When you shut the tractor off and it sits for a couple days, the resivor will become empty and brakes will loose prime. Thanks for everyone response.

 

[MARK ROBKE]

Yes I have replaced all 6 o rings. That was the first thing I did. Then I replaced the master cylinders. When I replaced the master cylinders I noticed the stand pipe was fell down in the return line. I ended up just replacing the tank. Still having the same issue as before though. The tractor will bleed fine and have stein brake pressure. When you shut the tractor off and it sits for a couple days, the resivor will become empty and brakes will loose prime. Thanks for everyone response.

The reservoir empties because something below it is leaking, could be the line(s). Or the o rings. As I said, the air pressure was not reliable for me. And as Jim said you can cut the o rings and not notice. Did you pull the fuel tank and the seat platform? You really can't pull and install the axle housing with them in place. I followed up after someone did that, and the brakes did not work for him-he cut the o rings. Mark. PS, I replaced a bunch of o ring seals on those brake pistons and never really saw one that looked obviously bad.

 

[Km722]

Yes I pulled the seat and tank when I replaced. Is there an easy way to test the o rings without tearing them all back apart again?

 

[Km722]

I can stand on the pedal and the pedal doesn’t sink down. It’s just after it sits for a couple days that it looses prime. I just don’t want to have to tear it all back apart if I don’t have to. Thanks

 

[MARK ROBKE]

Yes I pulled the seat and tank when I replaced. Is there an easy way to test the o rings without tearing them all back apart again?

Not that I know. I always had high hopes for the test, but no real joy with the set up I had. Mark.

 

[JimB2]

Next step would be to see if you can isolated the problem to one side or the other, probably easiest way is to block the line out of the reservoir to the master cylinder.

 

[Km722]

Next step would be to see if you can isolated the problem to one side or the other, probably easiest way is to block the line out of the reservoir to the master cylinder.

I pinched off the lines feeding the master cylinders from the reservoir one side at a time. The tank is bleeding down on either side at the same rate. I will add that I did order the master cylinders from eBay, so I don’t know if I fully trust them. I’m starting to wonder if they are bypassing through internal. Do you think the new master cylinders could be leaking internal, or do you think it would be something downstream (o rings). I do not see any external leaks.

 

[JimB2]

I believe if the master cylinders were leaking there would be oil on top of the transmission case.
Another option is to replace the bleeder screw with a barbed fitting and some tubing and external bottle of oil held up on top of the fender and see if it leaks down and repeat for both sides. I am trying to remember where the brake line actually connects into the brake piston but I believe like the bleeder screw it is via the top cover and there is a pass thru hole with O-ring between top cover and brake piston cavity???
Is there any indication the top cover has been removed for parking brake replacement?

 

[Km722]

I believe if the master cylinders were leaking there would be oil on top of the transmission case.
Another option is to replace the bleeder screw with a barbed fitting and some tubing and external bottle of oil held up on top of the fender and see if it leaks down and repeat for both sides. I am trying to remember where the brake line actually connects into the brake piston but I believe like the bleeder screw it is via the top cover and there is a pass thru hole with O-ring between top cover and brake piston cavity???
Is there any indication the top cover has been removed for parking brake replacement?

I guess I meant I didn’t know what’s supposed to hold fluid in the resivor. Like if I were to take the line off the master cylinder feeding the brakes if fluid would drain out of the outlet port. Or are the o rings supposed to hold the fluid in the resivor. If that makes sense.

From what I can tell the top cover has not been off. Would that give me access to the brake cavity you are talking about? Maybe something inside there is leaking off?