Can't move rear diff locker lever

[thedoeges]

All right,

I am a c303 owner, yet I am posting here....

My father in law owns a Pinz 710 model, and we were unable to move the rear diff lever down. We opened the rear diff hydraulic drain, exercised the lever down, hydraulic fluid streamed out as we were moving the lever, tightened up the screw, and were able to engage and disengage the rear diff, but only for a few times before the lever was stuck in the up position again, while the rear diff actually stayed engaged. We drained again, and it worked for a few cycles, before locking up again. Meanwhile, of course, the hydraulic reservoir level goes down a little while draining. Any idea what could be broken?

Thanks.

Marcus

[krick3tt]

You may need a power bleeder and new valves. Completely flush the system. Use a vacuum of some type to clean out the res and start again with new fluid. I used a turkey baster to draw out the dirty fluid.
While you are there do them all...only three to do. Check your elbows and 'T' rubber bits and perhaps get new ones.
I have done this, it is not a difficult job...and I know it can be somewhat frustrating to not get the thing to work. Don't try to work the levers up and down, they will break off at the connection.
Check Ebay as SAV has parts on there you need to replace it all now.

[edzz]

look here

viewtopic.php?f=13&t=6569&hilit=lever+stuck

[John L]

The guys are correct, as usual. DON"T force the lever down like I did or you will be repairing the broken lever as well. Your problem should totally be fixed with a power flush and replacement of the fluid, bleeder valves on the exterior of the truck if need be, and replacing the elbows and t's as suggested. When my fluid came out, instead of clear it was coca cola colored with yellow floaties. After the flush and replacement of a few parts she's as good as new.

John L

[berger]

Duplicate

[berger]

Flushing fluid and replacing elbows doesn't cure this. Mine still does it from time to time, but only when I use a locker, take the front, then disengage, then try to engage again to quickly. Not always, but sometimes. I just drive a few more meters and it works again.


Sent from my Mobile

[undysworld]

Flushing fluid and replacing elbows doesn't cure this. Mine still does it from time to time, but only when I use a locker, take the front, then disengage, then try to engage again to quickly. Not always, but sometimes. I just drive a few more meters and it works again.

IIRC:

The actual mechanism which locks the drive train is spring loaded, so when you push down the lever and force hyd. fluid into the slave, it moves the spring. Then when the drive lines align, the spring forces the collar to lock. When you unlock the locker, no fluid is pushed back to the master until, and unless, the actual lock mechanism unlocks. If there is binding on that section of the driveline, the lock mechanism can't retract and push the fluid to the master, so when you try and force extra fluid in by again depressing the lock lever, you can't. The fluid won't compress.

Continued driving will typically cause the lock to unlock by relieving the strain on the driveline allowing the lock mechanism to unlock.

[totaljoint]

Last winter it took a mile or so after I unlocked the rear locker in snow for the green light to go out. It wasn't especially cold and I didn't have the
same trouble with the front or middle locker.
It always unlocks quickly and only that one time stayed stuck. Fluid's changed yearly.
Can I blame that on cold fluid?

(I follow Jim's and Andre's advice to flip all levers until the lights come on, on straight a-ways every time I take the Pinz out year round to keep the hydraulics moving and not gum up.)

[undysworld]

I wouldn't think so, if all the lines were flushed recently. When you say "fluids changed yearly", which fluids? Did all the locker hydraulic lines get flushed with freshly opened brake fluid?

Maybe water in the locker mechanism freezing?

[krick3tt]

I was told that one should only use 'fresh' brake fluid as an opened can that has been sitting will absorb water and cause problems for the system...perhaps freezing.
It's the little things.

[undysworld]

Morris,

Yeah, brake fluid very aggressively absorbs water. (That's why you only used freshly opened stuff, and flush the system occasionally.) But that doesn't explain why only one line would have water in it.

If all the lines got flushed with the same fluid, then they should act similarly, I'd think. But the rear is the longest line of them all, so maybe the fluid got just slushy and stiff and being longest had the most restriction.

Another possibility is a stuck bleeder, and only the other two lines got flushed?

Or maybe "fluids changed yearly" only refers to the gearboxes...?

[berger]

This is something I never understood about brake fluid. So, if I buy a bottle larger then I need, do I throw away the remainder???

[undysworld]

So, if I buy a bottle larger then I need, do I throw away the remainder???

Yup, as I understand it, unless you can use it up really fast. You can reseal it really tight, but whatever moisture is in the air in the bottle will absorb into the fluid.

As a curious demonstration, buy a small bottle and leave it open on a humid day. Before long, the bottle will overflow.

I got lucky and bought a box of small bottles for $1 each. That way I never have much left over.

[TechMOGogy]

Vacuum seal it and you can keep it for years

[Stekay]

So, if I buy a bottle larger then I need, do I throw away the remainder???

If it was a humid day in the Amazon, I AND I used more than half of a large bottle (so there's a lot of air in there) I might throw it away. If it's a lower boiling point you're worried about, well that doesn't apply to the Pinz, unless you have disc brakes in a TD. If you're worried about corrosion, there's probably already more in there than the slightly contaminated fluid would ever add do to a small amount of moisture.
Just my thoughts on the subject.