Stumped by drum brake/hub assembly
Discussion
Afternoon all,
As part of my weekend work I'm trying to disassemble a drum braked axle to rebuild the cylinders with new seals. I am trying to remove the backplate complete with cylinders and shoes still attached letter, to work on the lot of it together on the bench.
Based on my experience with Land Rover axles, once the brake line has been disconnected from the cylinders, the backplate simply unbolts from the axle tube and slides off over the hub bearings.
This axle is from a 40s/50s US light truck, possibly GM, but I don't know which. The backplate is held onto the axle with 6 bolts, 4 of which I removed, 2 of which the nuts had rusted to nothing (probably from fluid dripping on them) so I drilled and chiseled the heads off. The holes the bolts pass through are not threaded.
By my logic, the backplate should now come off, but it will not budge. What is confusing matters is the very unusual pinch-bolt wheel bearing/oil seal arrangement inside where the drum would be - I cannot tell if:
A) this must be removed first to get the backplate off
B) the casting and backplate are in fact one assembly
C) the backplate is simply rusted to the axle tube and just needs an even bigger hammer to persuade it.
I'm fervently hoping the answer is C, but can anyone with experience of this arrangement please shed some light?
Thanks,
Matt
Hub assembly:
Closeup of weird seal casting:
Join of backplate and casting - one piece or just rusted on?
View behind backplate:
As part of my weekend work I'm trying to disassemble a drum braked axle to rebuild the cylinders with new seals. I am trying to remove the backplate complete with cylinders and shoes still attached letter, to work on the lot of it together on the bench.
Based on my experience with Land Rover axles, once the brake line has been disconnected from the cylinders, the backplate simply unbolts from the axle tube and slides off over the hub bearings.
This axle is from a 40s/50s US light truck, possibly GM, but I don't know which. The backplate is held onto the axle with 6 bolts, 4 of which I removed, 2 of which the nuts had rusted to nothing (probably from fluid dripping on them) so I drilled and chiseled the heads off. The holes the bolts pass through are not threaded.
By my logic, the backplate should now come off, but it will not budge. What is confusing matters is the very unusual pinch-bolt wheel bearing/oil seal arrangement inside where the drum would be - I cannot tell if:
A) this must be removed first to get the backplate off
B) the casting and backplate are in fact one assembly
C) the backplate is simply rusted to the axle tube and just needs an even bigger hammer to persuade it.
I'm fervently hoping the answer is C, but can anyone with experience of this arrangement please shed some light?
Thanks,
Matt
Hub assembly:
Closeup of weird seal casting:
Join of backplate and casting - one piece or just rusted on?
View behind backplate:
I've come across both designs but in this case it doesn't look like the back-plate has any chance of clearing the bearing assembly even if it is a separate part? Can you not remove the cylinder, shoes, etc. from the back-plate without removing the back-plate from the axle?
Edited by kambites on Friday 27th February 11:48
Thanks chaps.
I didn't want to remove the plate, but the fixings for the cylinder, and pipe unions on it, are one big lump of corroded mess. As you can see, there isn't the light to see or the space to get my head or any big tools in behind it - any undoing of nuts has been by feel.. which is fine if the nuts are still not shaped and not siezed
Even if it would not come off, I can still pull it forwards and spin it round to get proper access to the fittings
I didn't want to remove the plate, but the fixings for the cylinder, and pipe unions on it, are one big lump of corroded mess. As you can see, there isn't the light to see or the space to get my head or any big tools in behind it - any undoing of nuts has been by feel.. which is fine if the nuts are still not shaped and not siezed
Even if it would not come off, I can still pull it forwards and spin it round to get proper access to the fittings
ChemicalChaos said:
Thanks chaps.
I didn't want to remove the plate, but the fixings for the cylinder, and pipe unions on it, are one big lump of corroded mess. As you can see, there isn't the light to see or the space to get my head or any big tools in behind it - any undoing of nuts has been by feel.. which is fine if the nuts are still not shaped and not siezed
Even if it would not come off, I can still pull it forwards and spin it round to get proper access to the fittings
Use more hammer and some chisel. I didn't want to remove the plate, but the fixings for the cylinder, and pipe unions on it, are one big lump of corroded mess. As you can see, there isn't the light to see or the space to get my head or any big tools in behind it - any undoing of nuts has been by feel.. which is fine if the nuts are still not shaped and not siezed
Even if it would not come off, I can still pull it forwards and spin it round to get proper access to the fittings
Doesn't look like it'll clear that bearing/seal housing.
Having said that, get a proper hammer, some earplugs and most importantly a large blow lamp.
Warm the seized area up, the plate should expand/heat quicker than what it's seized to, meaning you can give it some more hammer action and off it'll come.
Don't set fire to everything and warm it, don't make it glow
Having said that, get a proper hammer, some earplugs and most importantly a large blow lamp.
Warm the seized area up, the plate should expand/heat quicker than what it's seized to, meaning you can give it some more hammer action and off it'll come.
Don't set fire to everything and warm it, don't make it glow
I would say that the pinch bolt holds the locking tab in, which can be seen between the two halves.
once that's flicked out the way the castle shaped locking nut can be either punched round (or undone with the proper castle faced box spanner)
once that's undone, I guess the half shaft will come out.
the backplate looks as if it would wriggle over the pinch bolt 'lump' so I bet its just rusted on to the axle.
I also bet that the two bolts you had to drill out where rivets, done in the factory so the back plate couldn't be removed in service and then fitted upside down in error.
I think I would just do the brakes in situ................
once that's flicked out the way the castle shaped locking nut can be either punched round (or undone with the proper castle faced box spanner)
once that's undone, I guess the half shaft will come out.
the backplate looks as if it would wriggle over the pinch bolt 'lump' so I bet its just rusted on to the axle.
I also bet that the two bolts you had to drill out where rivets, done in the factory so the back plate couldn't be removed in service and then fitted upside down in error.
I think I would just do the brakes in situ................
Edited by guru_1071 on Friday 27th February 12:37
Doing the brakes in situ is actually easier than taking the whole lot off
You need to remove that big bearing carrier thing that I can never remember the proper name of, the back plate will be sandwiched between that and the axle (with gaskets both sides I expect).
You will probably need a puller/lots of heat/swearing to get it off, good luck.
Should have just done them in situ !
Hi all, thanks for the replies and advice.
Today I doused the joint in penetrating fluid and applied the Engineers Persuasion Tool No.1
Result! The backplate soon sprang free from the axle, and even better it just about fitted over the pinch casting too! Turns out the pinch casting is actually part of the axle tube rather than a separate part attached to the flange.
Here's the axle all cleaned up:
And to answer an earlier question, here's one of the top two bolts that was refusing to undo and had to be drilled. Turns out it wasn't an anti tamper job, just corroded to nothing! I can only guess that brake fluid has leaked onto it over the years
Today I doused the joint in penetrating fluid and applied the Engineers Persuasion Tool No.1
Result! The backplate soon sprang free from the axle, and even better it just about fitted over the pinch casting too! Turns out the pinch casting is actually part of the axle tube rather than a separate part attached to the flange.
Here's the axle all cleaned up:
And to answer an earlier question, here's one of the top two bolts that was refusing to undo and had to be drilled. Turns out it wasn't an anti tamper job, just corroded to nothing! I can only guess that brake fluid has leaked onto it over the years
ChemicalChaos said:
Hi all, thanks for the replies and advice.
Today I doused the joint in penetrating fluid and applied the Engineers Persuasion Tool No.1
Result! The backplate soon sprang free from the axle, and even better it just about fitted over the pinch casting too! Turns out the pinch casting is actually part of the axle tube rather than a separate part attached to the flange.
Here's the axle all cleaned up:
And to answer an earlier question, here's one of the top two bolts that was refusing to undo and had to be drilled. Turns out it wasn't an anti tamper job, just corroded to nothing! I can only guess that brake fluid has leaked onto it over the years
Would the cylinders andToday I doused the joint in penetrating fluid and applied the Engineers Persuasion Tool No.1
Result! The backplate soon sprang free from the axle, and even better it just about fitted over the pinch casting too! Turns out the pinch casting is actually part of the axle tube rather than a separate part attached to the flange.
Here's the axle all cleaned up:
And to answer an earlier question, here's one of the top two bolts that was refusing to undo and had to be drilled. Turns out it wasn't an anti tamper job, just corroded to nothing! I can only guess that brake fluid has leaked onto it over the years
brake lines not be dissolved by the fluid if it could do that to the bolts?
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