Looking for anyone who has done done work on the zf axles on the ta400 haul trucks. I'm putting a hub back together had a brake piston seal failure. I have new seals , new brake friction discs.My issue is the dual cone seal on the brake package size with the thicker toric will halfway seat with a seal installer , and deadblow hammer ,but if pressure is applied it will seat fully but once pressure is removed it pops halfway out.I don't know what is happening or what I'm doing wrong I followed the steps in the service manual , my planetary hub part of the seal is seated perfectly fine. Everything is lining up fine it's just the seal on the brake side has so much tension or pressure when you put the hub together , and installed everything and your axle but the hub will stop rotating once you start to tighten it. Any tips , or advice are appreciated.
Seem to recall using windex to help roll that seal in so it would not roll back out. Maybe type in search bar for Toric seals. Been years since I done one, but that is what I recall. Simon C
That was Windex in a can as the alcohol part evaporates in 2 minutes or less. Simon C
My thing is the seal is halfway into the groove it is supposed to sit in am I supposed to seat all the way or is it supposed to sit halfway because muy dual cone on the planetary hub side is completely seated but when I lift it into place I mesh with my friction disc hub spins but when I tighten it down my hub stops spinning I have to torque it to 1400-1600 ft lbs when I get it to 500 ft lbs it locks down hub not longer spins , and I have a gap about the size of the amount seal that is not seated on the brake package side.
What procedure does the service manual require.? Any lubricant or similar.?
So I am not there, my question is would it turn easier if the toric seal went in further. So is it the inner lock that is 1500 Ft lbs or the outside lock that is. Maybe post a picture and myself or someone else might better be able to suggest solution. Could you have a bearing race seat that is not seated. Simon C
I spoke with rokbak/terex support they said that for dual cone seals they use brake cleaner , or starting fluid and that using a seal installer it should pop into place.
The side view of the clean hub is now , the side view of the dirty hub is the before disassembly the 3rd pic is the axle slotted nut before removal , the hub had some free play to it like it should before disassembly my thing is I'm not getting that same gap between the hub like original side view that's dirty I shouldve cleaned it in hindsight. I can get more photos tomorrow.
The clean hub sideview photo is with everything on and axle but right hub does not spin anymore
And axle is tight but hub does not spin anymore* typo.
This is as far as I can get without the seal just popping back out at me.
Does the Toric Ring "roll" as you press the seal inwards with the installer tool, or does it simply slide down the "knurled" ramp in the brake housing.?
It will roll towards the backside of the face ring and pop out the backside it almost seat but popped out the backside
That's what I got now that's as far as it will go before it pops out the back. It will also cause the axle to not spin when you try to put the planetary hub , and everything back on and tighten the slotted nut down
Is the replacement seal OEM or aftermarket.? How do the Toric Rings compare size-wise to the old seal.?
OEM terex part same size as the original.
In that case I’m sorry I don’t have any other ideas.
Make sure that the Oring isn't twisted, apply pressure the metal ring and use a plastic, narrow spatula, spoon, or trim tool to walk the Oring inward in stages. At least, that's how do them. And the bore the Oring goes into must be corrosion free.
have you tried to assemble without the seal to confirm it is the problem?
Yeah we put it together without the seal, and the gap closes.
remove seal ass , clean inner bore, making sure there's no dirt or build up of oil or rust refit oring you can use a liquid soap on the outside of oring it wash off. did you get supplied the go/no-go gauge block to check hi of assemble seal?
I found the issue so the tool kit to do the job you get a splined mandrel tool to line all your friction discs when we install it onto the spindle it was only meshing with 4 out of the 5 discs teeth.All this trouble because the very last disc teeth were not catching the teeth on the clutch disc.
The way I found this out was using a borescope camera and saw the last disc was just barely on the tool. When you took a flash light and looked at the tool it looked as if all the disc were seated they weren't.Everytime we put the tool on we thought we were catching all the discs but we ended up having to take a deadblow an tap the half of the tool that meshes with the discs further back off of the removal side of the tool.
I've never seen a duo cone seal get so tight that it causes sufficient friction to prevent turning a hub. The way they are ground there's not that much surface area there to cause that much friction, at least in my mind. Are you sure the duo cone seal is the correct part?
It sounds to me as though they didn’t get the splines of all the brake discs lined up correctly, and so the hub splines came tight up against the teeth of the inner disc in the stack instead of sliding past them. The pressure from this misalignment is what would have bound up the wheel and stopped it from turning.
Correct 4 of the clutch/friction discs were on the planetary hub when going back together when using the splined mandrel tool supplied the tool would grab all 5 disc but the 5th disc wasn't seating on the tool so it would drop ever so slightly where when going back together the disc would t grab onto the planetary hub we had to actually use a deadblow and tap the tool further back then it would grab the 5 disc then apply air to the brakes to hold pressure then everything went smoothly we actually had to tap the hub itself with a deadblow while put the the hub through the discs it was a very irritating labor intense process resetting everything.
That’s the main reason why rebuilding finals/Duo Cones with the axle horizontal is such a pain. It’s so hard to stop the friction discs/plates from moving out of position.