Brake fairy reqd

[Eightpot]

Still having probs with the brakes on this wretched thing, appreciate any fresh ideas -

I've recently replaced the discs, pads, cleaned up the calipers, had the rear drums off and cleaned the dust out and checked all works ok.

The brakes were still not very good, and it turns out the servo was duff (whole braking system was pretty bad, looks like the car was left standing before I got it)

Put a new servo on, and braking mucho improved, but now the brakes seem to be grabbing on after I start moving off from a standstill... if I start to accelerate in 1st, it gets about ten feet then the car slows right up needing full throttle to keep moving at all.

I was suspecting collapsed brake hose, but wouldn't this only affect after braking and releasing the brake pedal?

Not sure if there is something else maybe binding up the transmission perhaps, but checked the VCU and that seems ok.

Any thoughts?

[errol209]

cleaned up the calipers, had the rear drums off and cleaned the dust out

Did you replace the pistons and seals on the front? They don't move much normally and corrode like nothing else (generally in the on position). Did you remove the shoes and put them back? If so, did they go back the right way round (leading / trailing) with all the springs on?

[Eightpot]

I stripped the calipers down, cleaned them up and replaced the existing pistons/seals. The pistons had a few light marks on but not particularly worring, seals were intact and fluid tight so I reused them. Calipers themselves were badly rusted on the outside.

rears seem ok, handbrake works fine and when I got the car the fronts were seized and only the rears were stopping the car, so I have no reason to suspect they are at fault - I took the drums off, brushed the dust away, had a look and all looked normal so didn't go any further.

Before I changed the servo, the brakes were working ok, although obviously not with as much force, but there was no binding or this problem of them seeming to suddenly come on at low speed - i seems to go away once past 15mph. It's only since I put a new servo on today that this new prob has manifested itself.

S'pose the new servo is amplifying stuff that previously wouldn't have shown up and I need to replace more bits - I do suspect the hoses but have little experience of freelanders so perhaps there is another explanation?

[errol209]

It's only since I put a new servo on today that this new prob has manifested itself.

Bear with me, 'cos I've never even driven a Freelander, never mind replaced a servo, but a few more suggestions / questions:

There is probably an adjuster on the servo unit (the bit that sticks out into the end of the master cyclinder) to take up any slack. If this was too sticky-outy then this would have the effect of holding the brakes slightly on. Why this problem might go away at 15mph I have no idea yet!

Failed hoses balloon out if they don't rip apart first, so I suppose it might be possible that in stopping you store some brake line pressure, but I've never come across it. You'll need a willing pedal presser, eyes like a hawk and a light touch to find a bad hose, but big cracks are a dead giveaway.

Does the problem go away quicker if you run and rev the engine as if you were driving at 15mph for a while prior to moving off? That question is aimed at the vacuum state in the servo vacuum chamber, and is along the same lines as the servo adjuster question.

Last question: with the engine off, press the brake pedal lightly and start the engine. What happens? Does this make the "going away" happen sooner, later or no difference?

Really the last question: do you have any of the following: ABS, TCS, brake pad wear sensors, ASR.

[FridgeFreezer]

Duff brake hoses shouldn't cause brakes to bind or be able to store pressure. My bet would be something like sticking calipers.

[Eightpot]

This is nonsense. I've never had anything like this before - I don't actually think it's the brakes. Applying the brakes works fine and releasing them does what it should. They are good and sharp and pull up straight.

After pulling away, progress is arrested fairly smartly, as if a mystery third foot had snuck in and was pressing the brake pedal.

I've just sprayed some black paint on the discs to see if it was cleaned off after the problem manifested itself. As expected a little was wiped off but by and large the paint is still on the disc.

It feels like it may be something possibly in the transmission - I haven't got to grips with the whirly bits on Freelanders yet, but it feels like it would if the transmission brake was applied on my 90 while I was driving off. Its a stronger force than can be applied with the freelander handbrake, so I don't suspect rear shoes.

There is a bit of a throbbing noise underneath and I just had a clunk from the rear when taking a corner.

It's only done 67k, so I'm a bit miffed - better get meself aquainted with a haynes book.

Another thought is ABS/HDC - could this be grabbing me back?, it does only seem to do it in 1st & 2nd gears, also the light has just stopped coming on if I select HDC. I'm not getting an ABS type judder though.

[rustymark]

Hi

HDC is controlled via the brake ECU - on my td4 (2000) its built into the ABS modulator which is in the engine bay - other models have it under the drivers seat.

You cannot select HDC (to operate) in any gears other than 1st and reverse. If it is switched in and you're in neutral the green HDC light will flash.

An ABS fault (usually signified by HDC (Green) ABS Warning light (yellow) and TC (yellow)) lights on all the time - if you have this search 3 amigoes on here.

TC will only activate in low gears and normally when moving off, the ABS applies brakes to spinning wheel and you can feel it (thud thud thud ABS style) and the TC light comes on.

Something in the drive train is slowing you IMHO - you may have to wait for an adult to appear on here who knows the fault. To me maybe the VCU is not allowing any slip and locking drive train solid. A clunk at rear could be final drive or CV joint or rear sub frame or...........?

[Eightpot]

I've just tried with the servo vac hose disconnected and still it does it, so I don't think it's brake related.

I'll have to try whipping the prop off and see if that makes a difference, I know these things suffer with VCU probs, though I'm struggling to comprehend how that would suddenly bring the car down to a crawl at low speed, but be ok at higher speed.

oot with the spanners again...

[FridgeFreezer]

After a strange happening this morning with similar symptoms I found a rear brake shoe had lost its lining, which was jamming in the drum and causing the rear wheel to lock up solid with even very gentle brake applications. Reversing up a few inches freed it enough to continue driving until the next screeching halt.

Happily the motor factors next door had a set on the shelf and it was the work of a few minutes and a couple of skinned knuckles to replace them.

If you have rear drums, whip the back wheel off, undo the two philips screws on the drum face, and with the handbrake off pull the drum off. It may require tapping / rotating / prying to make it come off, especially if a shoe has gone faulty inside.

[Matt Neale]

I had a similar thing on my 110 after I changed the servo.

I don't know if this will apply in your case, but on a Defender, there is an adjustment on the mounting face of the servo - a small grub screw which adjusts the preload between the servo and the master cylinder. If the set screw is wound out too far, it pre-loads the braking system and causes the brakes to bind.

Adjustment is easy - separate the master cylinder from the servo to access - no need to break into the fluid lines.

Like I said - not having had cause to change a m/cyl on a freelander, I've no idea if the above will apply - so apologies if this only adds to the confusion!

Matt