Humpty Dumpy

[cobbadog]

It has been a very long time since I have posted a thread here so here we go again. Our Liner Roughrider has never had a hand brake but I did manage to rig up a wire cable to make do but now is the time to make the proper linkage. Last time I had Humpty out his foot brake was not as good as it use to be and I noticed some oil on the wheels. A sure fire sign of leaking axle seals. So today I shuffled the David Brown Cropmaster around with Humpty so I had better access to the drive wheels and brakes. I jacked him up and sat him on some stands. Before doing that I loosened the wheel nuts and the centre hub nut as well. Wheel off on one side only first then came the removal of the brake drum. No holes for jack bolts so I backed the adjuster right off so that the drum could rotated by hand with no linings touching.
No go, even after using a soft nylon hammer to bump the outside edge it looked as if it may have moved a little bit but even hitting it back on in that one area it still would not release. Our with the bunsen burner as I call it. A small LPG bottle with a "C" or #3 size burner on it ideal for heating. A trick I learn a while ago was not to heat the middle area but do the opposite, heat the outter edge. My reasoning for this is that the outter edge allows for expansion quicker than trying to heat and expand the centre and try to push the outter edge out while cool. This worked a treat again. On this model the drum centres on both the centre hub and all 5 wheel studs that have a shoulder on them right against the hub itself. You can see these shoulders in the last 2 pics.
Next was the centre hub. With the nut right away from the hub there was no sign of movement to come off. So with my trusty large sliding hammer I used it, but still no go. So back out with the bunsen burner and gave it a bit of heat treatment and then the slide hammer but still no go.
So at this stage I had thought about how a cuppa would be in order so packed up and went inside to dribble on about it here. Tomorrow, weather permitting I will attack it again with heat then squirt some Lanox inside where the hub slides onto the axle so that the Lanox will be drawn inside to help release it. This side is not so bad with the oil leak but has signs on the wheel so it is going to get a new seal.
Wish me luck and please tell me if I am going about this wrongly. I think that the row of nuts on the inside area of the brake backing plate only holds the plate to the diff housing.

[cobbadog]

Any diagrams on the brake system please?

I have at the moment a large 3 leg puller under a lot of strain, have applied heat again plus have hit the centre of the hub with a cold chisel opposite the keyway and so far the hub is not moving. You can see the chisel mark, I put white marker pen on it.

So now I am not sure if there is something else I have missed to loosen or undo to allow it to release or is this mongrel just being stubbourn?

[cobbadog]

Pics

[gecko.cx]

I've never found a propane torch to be very effective in situations like this. My thought is that the heat transfer from the flame to the hub is about the same as from the hub to the axle, so you don't get the differential movement needed the break the joint.
Can you get your hands on an Oxy set? The higher temp flame will heat it more rapidly may make the difference.

Heating it (with propane) and then spray with WD40/eqiv. a few times as it cools may work the stuff in.

[cobbadog]

I agree gecko with your comment on the LPG burner, even though it is so large. Yeah oxy would be far better but I dont have it nor know anyone with it anymore. Right now there is still a lot of tension on the puller to the point I cant get any more fetch on it unless I use some pipes over the tools to get more tension on it. Tomorrow is another day so after doing the lawns before the rian starts I will have another go. I dont give up too easily.
Thanks for your comment mate.

[Jeremy Rowland]

Bit of an awkward job there Cobba, must say I have never removed this type of hub/half shaft arrangement before, you could do with some pressure from the puller and a way of clouting it at the same time, good luck with it let us know how you get on.

Jeremy

[cobbadog]

Well I went back to face the music late morning and had another go at it. At that stage I actually undid the puller and fitted the nut back onto the shaft just incase it did let go and wiped out our house and the one across the road. This time I put a bar in place to lock the hub up and then a pipe on the spanner to tighten the puller even more. I also have a 1" diameter brass drift about 8" long and used my brickies lump hammer and have been flogging the hub in close where it goes around the axle shaft. To the point it is now being brass impregnated. I also applied some more heat around the outter area away from the centre but still no go. All the time I have been squirting some Lanox onto the thread and behind the hub hoping that it gets in from that side.

I am right in thinking that this hub is just sitting on a taper on the axle and then a woodruff key is also keeping it from spinning on the axle?

gecko I have not ignored your helpful comment but need to try everything else first. Then lucky me gets to do the other side too.

[cobbadog]

I did not get to spend any time on Dumpy today or very little. I was offered some info that a similar hub set up was used onan International 1100 model light truck. If this is the case I need to make a sleeve which I started to make that fits over the axle thread but inside the hub and knock a tapered sleeve inwards.
Another idea thrown out there is to hit the hub back in then try pulling it out. Tomorrow I am off to a mates place to borrow his hydraulic puller. I will have more pics and info tomorrow, I hope.

[gecko.cx]

My feeling is brute force will be what's needed and a hydraulic puller may do the trick.

Thinking about applying heat - you'll get the most benefit where the metal is the thinnest - around the keyway.

[Jeremy Rowland]

My feeling is brute force will be what's needed and a hydraulic puller may do the trick.

Thinking about applying heat - you'll get the most benefit where the metal is the thinnest - around the keyway.

Must say I tend to agree that may be the way forward.

Jeremy