Clunking from rear of Defender

[Paul64]

Hi,

On my way back to the UK I developed a clunking at the rear of my Defender. It usually happens at low speed when the clutch is put down at the point when there is slight deceleration. I initially thought it was the prop shaft but all seemed well on inspection. As rejo is sunning himself somewhere in eastern Europe I took my LR to Haywards 4x4 near Fakenham in Norfolk. They checked it over and said after some looking that they thought it was the half shafts and or the end caps. These were replaced and all seemed well until the long drive home today. The noise returned! It seems to be much worse when on a long run. Any ideas?

Cheers,

Paul

[ibexman]

Hi,

On my way back to the UK I developed a clunking at the rear of my Defender. It usually happens at low speed when the clutch is put down at the point when there is slight deceleration. I initially thought it was the prop shaft but all seemed well on inspection. As rejo is sunning himself somewhere in eastern Europe I took my LR to Haywards 4x4 near Fakenham in Norfolk. They checked it over and said after some looking that they thought it was the half shafts and or the end caps. These were replaced and all seemed well until the long drive home today. The noise returned! It seems to be much worse when on a long run. Any ideas?

Cheers,

Paul

sounds like mainshaft where it goes into transfer box?????

[Mark90]

That or the A-frame ball joint are my guesses.

[ibexman]

That or the A-frame ball joint are my guesses.

mind you ive had clunking from rear radius arm front bushes

[Paul64]

Thanks,

A frame ball joint has no play in it and polybush reds were put on rear radius arms 3 weeks ago. What bothered me about the half shafts was the really bad wear on the splines. However, if the male end looks that bad, what are the female ends going to look like which are still in there?

[Diff]

Hi Paul,

Since you say it happens at low speeds when the clutch is pressed and coasting, I suggest that it sounds like the handbrake is binding/not releasing fully. This can create a lot of clunking and shunts in the prop and rear axle when going slow.

It may be worse when the gearbox is warm?

Regards,

Diff

[Paul64]

Hi Paul,

Since you say it happens at low speeds when the clutch is pressed and coasting, I suggest that it sounds like the handbrake is binding/not releasing fully. This can create a lot of clunking and shunts in the prop and rear axle when going slow.

It may be worse when the gearbox is warm?

Regards,

Diff

Thanks Diff,

Now you mention it, it all started when queing for the ferry going to the UK. Tried to pull away with handbrake on. Quickly released it, but the noise was particularly bad straight after. Any relation to that do you think? What is the solution if it is the handbrake?

Cheers,

Paul.

[Diff]

Thanks Diff,

Now you mention it, it all started when queing for the ferry going to the UK. Tried to pull away with handbrake on. Quickly released it, but the noise was particularly bad straight after. Any relation to that do you think? What is the solution if it is the handbrake?

Cheers,

Paul.

It is not uncommon for the expander mechanism inside the drum to get sticky. The grease dries out and or gets a little rusty which means that the shoes don't fully move away from the drum. Sometimes you can free it off a bit by giving the link or cable a wiggle as it goes into the drum, but this is only a temporary measure as it will stick again. Often the next time you use the hand brake!

If it is sticking, the best course of action is to remove the rear prop at the drum, slacken the shoes using the manual adjuster on the back plate, remove the drum and shoes. The expander is fairly easy to remove, strip, clean relube with moly grease or similar and reassemble.

I am not sure that you could have done anything significant by trying to pull away with the brake on, but it might have tweaked a shoe or the expander such that it has more of a tendency to stick.

Regards,

Diff

[Paul64]

It is not uncommon for the expander mechanism inside the drum to get sticky. The grease dries out and or gets a little rusty which means that the shoes don't fully move away from the drum. Sometimes you can free it off a bit by giving the link or cable a wiggle as it goes into the drum, but this is only a temporary measure as it will stick again. Often the next time you use the hand brake!

If it is sticking, the best course of action is to remove the rear prop at the drum, slacken the shoes using the manual adjuster on the back plate, remove the drum and shoes. The expander is fairly easy to remove, strip, clean relube with moly grease or similar and reassemble.

I am not sure that you could have done anything significant by trying to pull away with the brake on, but it might have tweaked a shoe or the expander such that it has more of a tendency to stick.

Regards,

Diff

Thanks for the information Diff. This sounds like a possible cause. Could this actually slow me down or cause damage to anything?

cheers, Paul

[GBMUD]

This sounds like a possible cause. Could this actually... ... cause damage to anything?

Yes. The friction material (brake lining) is glued to the shoes. If the brake binds and gets too hot then the glue is burned away and the linings may fall off the shoe and may get jammed in the system (which is rotating fast, low torque) causing the brake to jam and your rear wheels to skid. It is unlikely but possible, I have seen it happen once on a series 2a.

On my 200Tdi, there is a connecting linkage which goes into the backplate of the handbrake. On more than one occasion I have had to lie under the car and manually push this into the drum (it only moves 3/8" to 1/2") to free the handbrake. This works well until you forget and put the handbrake on next time you stop and then have to repeat the process - you can bet it will be raining by then.

I discovered that the expander mechanism can be cleaned in-situ. Remover the drum and shoes and you will be able to remove a piston and a small roller from top and bottom of the expander - note the orientation of the piston when you remove it, the inner end has a "ramp" on it and it must go back the same way. It will all become clear how it works when you get it apart. Mind, the pistons and roller may try to escape from the bottom one when you remove the shoes, I imagine you will find them well stuck though. Then you can disconnect the rod you pushed earlier from the external mechanism and remove the plunger from it. Give all the bits, including the expander housing, a good clean and reassemble. I use silicone brake slide grease (intended for sliding calipers) to lubricate and to hold it all together during reassembly. The silicone grease will not melt when it all gets hot, regular grease will.

Alternatively, give SimonR a call.

Chris

[Paul64]

Yes. The friction material (brake lining) is glued to the shoes. If the brake binds and gets too hot then the glue is burned away and the linings may fall off the shoe and may get jammed in the system (which is rotating fast, low torque) causing the brake to jam and your rear wheels to skid. It is unlikely but possible, I have seen it happen once on a series 2a.

On my 200Tdi, there is a connecting linkage which goes into the backplate of the handbrake. On more than one occasion I have had to lie under the car and manually push this into the drum (it only moves 3/8" to 1/2") to free the handbrake. This works well until you forget and put the handbrake on next time you stop and then have to repeat the process - you can bet it will be raining by then.

I discovered that the expander mechanism can be cleaned in-situ. Remover the drum and shoes and you will be able to remove a piston and a small roller from top and bottom of the expander - note the orientation of the piston when you remove it, the inner end has a "ramp" on it and it must go back the same way. It will all become clear how it works when you get it apart. Mind, the pistons and roller may try to escape from the bottom one when you remove the shoes, I imagine you will find them well stuck though. Then you can disconnect the rod you pushed earlier from the external mechanism and remove the plunger from it. Give all the bits, including the expander housing, a good clean and reassemble. I use silicone brake slide grease (intended for sliding calipers) to lubricate and to hold it all together during reassembly. The silicone grease will not melt when it all gets hot, regular grease will.

Alternatively, give SimonR a call.

Chris

Thanks for all the information Chris, I will give it a go. Just out of interest who is SimonR??

Cheers,

Paul

[GBMUD]

SimonR=The proprietor of X-eng He gives forum discount too.

Chris

[rejo]

Sunning myself in the C.Z.

Cheap food and its warm and sunny.

Jo

[Jon White]

Sunning myself in the C.Z.

Cheap food and its warm and sunny.

Jo

WTF???????????