Drum brakes

[Pedro_The_Swift]

I have been blaming the redarc pro controller for the erratic caravan brakes..


But how do drum brakes perform if never adjusted? or running low on shoe/pad/friction material?


The van brakes only ever apply flat out, there is no gentle brake application.
Yes the redarc is set to proportional.

The van is only 4 years old and is a dual axle 4 wheel 12" brake setup, though weight is 3.1T
could they be worn out? no funny noises or wheel locking/pulling to one side.

[Tombie]

Yes they need regular servicing and adjustment.

[Gordie]

Yes unlike disc brakes that are self adjusting...they need adjustment. The old rule of thumb used to be... wind the adjuster up until it was tight then back it off half a turn. I still jack them up and do the adjusters up, then back them off until I can spin the wheel.

[Rick1970]

Adjust,
but if they are very much out of adjustment, it’s a convenient time to pull the hubs, regrease bearings, clean, inspect etc….while the linings are clear of the drums and easy to get off.

[trout1105]

I have been blaming the redarc pro controller for the erratic caravan brakes..


But how do drum brakes perform if never adjusted? or running low on shoe/pad/friction material?


The van brakes only ever apply flat out, there is no gentle brake application.
Yes the redarc is set to proportional.

The van is only 4 years old and is a dual axle 4 wheel 12" brake setup, though weight is 3.1T
could they be worn out? no funny noises or wheel locking/pulling to one side.

Do you know how many K's the van has done?
Personally I would be taking the van into a brake specialist's and get the bearings inspected/replaced at the same time [thumbsupbig]

[gromit]

The electro-magnets that apply the brakes can also wear and sometimes need to be replaced.

With electric brake units there is usually a potentiometer that adjusts the rate of initial application of the brakes (digital or proportional). I'm not familiar with the Redarc but usually you head out for a drive and apply brakes several times while seeing whether the caravan tries to pull up the car or tries to push the car. By adjusting you get to a point where it's braking at roughly the same rate as the car.

Colin

[RobMichelle]

Few things could be wrong, brake magnet stuffed, back of magnet worn and turning on arm when applying, broken wire and one or two brakes working short in A frame brake wire.
Badly adjusted, as mentioned do up till firm, BUT, back off 10 turns, rotate hub if still dragging back off a couple more till spins freely.
Can also be out of shape backing plate from new.
I’d take it caravan repair and book it in

[Pedro_The_Swift]

Thanks every one, I do understand they need adjustment.
I had the bearings serviced before we left, if the brakes were worn wouldnt the Mech have mentioned it?

anyway,
The badly worded question was--

do drum brakes still work properly if out of adjustment,

I have to provoke them to get them to work on the highway, and its always the same amount of braking.

No, I have no idea on distance the van has travelled, though its never had a flat, and the tyres still had lots of tread before they failed.

I might take a wheel off....

[Pedro_The_Swift]

can you see shoe thickness without removing the wheel/drum?

[JDNSW]

do drum brakes still work properly if out of adjustment,

No

can you see shoe thickness without removing the wheel/drum?


No.

[OldGuy]

can you see shoe thickness without removing the wheel/drum?

You need to take the drum off which if the brakes are worn should not be too difficult, the drum is quite heavy. It will also give you the chance to check the actuator magnet.
Might be worthwhile trying to adjust them first, use a flat blade screw driver in the adjusting slot. I am pretty sure moving the handle end up on the left hand side tightens the lhs and down on the rhs to tighten the right hand brakes.

Good luck

[RobMichelle]

Same direction both sides to tighten ( flicking handle of adjuster tool downwards ) till they lock, then opposite way to loosen ( lifting handle of adjuster tool upward) 10 turns then spin hub if grabbing loosen off couple more turns. Apply 12 volt to brakes after adjustment to check hub locks on, remove power then spin again to make sure adjustment is ok.
12 inch hubs are heavy as mentioned yes mechanic should have picked up if there an issue if they were checked. Caravan repairs place most definately vehicle mechanics I’m unsure.

[RobMichelle]

Wondering if there’s grease or a leaking hub seal which has contaminated magnet and until enough friction has happened then the brakes apply aggressively, unfortunately you will need to remove all hubs to makes sure, and check the operation of each brake as ya go.

[DiscoMick]

Apart from servicing the van's brakes, you could also check the brake controller setting in your vehicle.
It should be set to bring the van's brakes on slightly harder than the vehicle's brakes, so the van doesn't push the tow vehicle, but can actually slow the vehicle on downhill runs, easing the load on the vehicle's brakes.
It should be possible to get the van's brakes to apply progressively. If the van's brakes go instantly to lock up, they may need adjusting.