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pbmps
01-14-2013, 02:39 PM
I have a steering problem on a D3B S/N X27y01837.The right track will not disengage when pressur put on brake peddel,but both tracks stop in push hard.Not a cat mec but sounds like the right cluch is stuck.THe cluch cly both work and the brakes are good.Pressure in the cluch clynders is about 200psi.If stuck is there a prescribed way to unstick without removing cluch?

dpendzic
01-14-2013, 03:20 PM
is it a dry or wet clutch arrangement? Is the linkage and valve end roller in good shape and linkage adjusted to spec?

pbmps
01-15-2013, 08:38 AM
is it a dry or wet clutch arrangement? Is the linkage and valve end roller in good shape and linkage adjusted to spec?

It is dry and all linkage is correct.Have operated the cluch valve by hand and the track does not even slow down.

Old Magnet
01-15-2013, 10:39 AM
Appears the slave cylinder that works the steering clutch yoke is stuck....not uncommon, especially if left to sit for long intervals. You will have to get access to pry the yoke (hopefully) loose.

pbmps
01-15-2013, 11:36 AM
Appears the slave cylinder that works the steering clutch yoke is stuck....not uncommon, especially if left to sit for long intervals. You will have to get access to pry the yoke (hopefully) loose.

The cly is working,checked that befor I put the cover back on.I took the cover off and found that the brake adjuster was frozen on both sides.Got them free and luberacated up and checked everything out .I did not take the cluch out.I thought the break adjustment being frozen was the problem.That was some of it but not all.

Old Magnet
01-15-2013, 12:41 PM
If all that's working then it's time to go deeper...checking the clutch release bearings and bevel gear cross shaft bearings. Looking for why the yoke movement is not getting transfered to clutch release.

pbmps
01-15-2013, 02:05 PM
If all that's working then it's time to go deeper...checking the clutch release bearings and bevel gear cross shaft bearings. Looking for why the yoke movement is not getting transfered to clutch release.

Should anything move when the Yoke moves.I could not see any movement in the area where the cluch is.How much should the yoke move.Does it move all the way to the stop or does it stop short of that point?
Also just put a new gage on the pressure test for the cluch cly.It reads 170 psi on the right and 250 on the left.Is this dif ok and what would cause the dif?

bob
01-15-2013, 04:53 PM
Should anything move when the Yoke moves.I could not see any movement in the area where the cluch is.How much should the yoke move.Does it move all the way to the stop or does it stop short of that point?
Also just put a new gage on the pressure test for the cluch cly.It reads 170 psi on the right and 250 on the left.Is this dif ok and what would cause the dif?

170 psi will not release your clutch enough. You need to take out both your clutch release valves and recondition them, new seals, springs and roller bearings. Maybe outer stems if worn and leaking at seals. Then when installed adjust the release linkage so the cams have 0.027" clearance to the rollers on the stems.
Later Bob

jonstark
01-15-2013, 06:45 PM
Have you changed the hydraulic filter and checked the pick-up screen?

As I recall you should see 400 PSI. (That's what I saw after changing mine.)

I'm with Bob on thinking the slave cylinders may be bypassing but you'll want to check these other items first.

jon

bob
01-15-2013, 08:13 PM
The steering valves are pressure reducing valves. The more you force on the valves the higher the pressure that goes through them.
Worn bearings on the stems reduces the travel and thus release pressure. Weak or broken springs inside do the same. Good valves will let full trans pump pressure through(app 400 psi)
Later Bob

pbmps
01-16-2013, 02:17 PM
The steering valves are pressure reducing valves. The more you force on the valves the higher the pressure that goes through them.
Worn bearings on the stems reduces the travel and thus release pressure. Weak or broken springs inside do the same. Good valves will let full trans pump pressure through(app 400 psi)
Later Bob

Thanks to Bob and the others that have replied to my problem.I took the right valve apart this morning.I think I remember someone saying a ball in the valve may have a flat spot on it. I dont see a ball,just two springs and a stem.No internal seals,just two "O" rings that seal both ends.Could someone send me a parts dia of the valve.S/N X27y01837.
Thanks,Paul

Old Magnet
01-16-2013, 04:35 PM
Does it look like this?....this is for an earlier 79U model, don't have the manual for 27Y.

The ball reference is for the later style that uses a ball bearing on the end of the stem. They tend to freeze up and wear a flat spot from rubbing on the cam.

dpendzic
01-16-2013, 06:37 PM
34375

this is my parts drawing for 27Y-03729

pbmps
01-17-2013, 08:23 AM
34375

this is my parts drawing for 27Y-03729

The internals look like it.
Thanks

pbmps
01-17-2013, 04:38 PM
Does it look like this?....this is for an earlier 79U model, don't have the manual for 27Y.

The ball reference is for the later style that uses a ball bearing on the end of the stem. They tend to freeze up and wear a flat spot from rubbing on the cam.

This one is similar but the next one is mine.
Thanks to all

dpendzic
01-17-2013, 09:05 PM
I guess it would pay to check out the slave cyl if the steering valve pressures check out as Bob stated.

pbmps
01-18-2013, 06:29 PM
The clynders work but I dont know if they are working enough.Do the have to extend all the way to the stop or do they stop befor they hit the stop.
Paul

Old Magnet
01-19-2013, 10:24 AM
The stops set the safe travel limit for the slave cylinders. I would expect the steering clutch release to occur near but before the travel limit. I'm sure it would be covered in the service manual which you need to obtain.

dpendzic
01-19-2013, 03:50 PM
my service manual gives the following

move the piston out of the slave cyl to 1 inch.
rod from piston gets adjusted so it is tight against the yoke--tighten lock nut
the stop bolt gets adjusted to .315 inches clearance between steering clutch housing and the bolt.tighten its lock nut

pbmps
01-23-2013, 10:47 AM
I do need to get a repair manual but beyond my retirement pay.Thanks to all for the help.I got it all put back together and after rebuilding the cluch valve on the right side,all is working.I still dont see how replacing the seals fixed it IF the orings were bad the valve would leak,At least that is the way I see it.Again thanks to all.
Paul