[shep]

what would cause the rear brakes of a lwb gaytara to lock on and stay
locked for half an hour or so and then just release?

[stocker]

Drum's Incorrectly Set?

have you just had them adjusted (or adjusted them yourself???)

[christover1]

MUD ?

squashed brake line impeding back flow. ?

bias valve issues. ?

Master or slave cylinders jammimg. ?

no idea really, just guessing.

[christover1]

Hand brake cable seizing

[buzbox]

I've got a few left over shit bits from when I did the disc brake conversion.

Various springs, handbrake adjuster, brackets and crap. If you need them gimme a yell.

[stocker]

hey dude, how much of a difference does that disc brake conversion make???

[shep]

the car has about 780mm of spring lift and the load sensing thing has had the spring removed.
tow truck has dropped it off at balls wogshop so hopefully he can sort it out.

[buzbox]

stocker wrote:

hey dude, how much of a difference does that disc brake conversion make???

umm how can I explain it.. It's made a BIG difference in braking performance.

Sure it's an expensive operation, but considering it's only about $150 more than new drums and shoes, It's money well spent. And in the long term it will save you money by 1, not having to replace the shoes as frequently as pads and 2, pads and rotors are cheaper than the shoes and drums.

[christover1]

buzbox wrote:

stocker wrote:

hey dude, how much of a difference does that disc brake conversion make???

umm how can I explain it.. It's made a BIG difference in braking performance.

Sure it's an expensive operation, but considering it's only about $150 more than new drums and shoes, It's money well spent. And in the long term it will save you money by 1, not having to replace the shoes as frequently as pads and 2, pads and rotors are cheaper than the shoes and drums.

X2

[royce]

lock on stay on once or lock on stay on all the time?

that load sense thing needs the spring, patrols do strange stuff with it off and I assume its a similar setup

otherwise has the pedal adjustment been fiddled with?

[shep]

it has done it twice now. the brakes, rear only i think, lock on and release 30 or so minutes later.

dont know about the peddle adjustment. maybe a longer spring or something on the load thingo.
i think ball is going to just remove the whole thing and stick a T fitting in to get it going again.

[royce]

rears will lock up ALL the time with it off

its backwards too, but he will fogure it if the bracket is still on the A arm, on mine I just bent he bracket with a prybar till it worked good

step one would be when it locks crack a line at the master and see if that releases it

[atari4x4]

did it do it when flexed up off road, could be the handbrake cables pulling tight?

[christover1]

shep wrote:

it has done it twice now. the brakes, rear only i think, lock on and release 30 or so minutes later.

dont know about the peddle adjustment. maybe a longer spring or something on the load thingo.
i think ball is going to just remove the whole thing and stick a T fitting in to get it going again.

load sensor is adjustable, I closed mine off completely and removed springs.
Now braking is always predictable.
NB bleeding needs to be done with lspv thingy disconnected, or only one line bleeds proper.
That could be all crap,
but it worked on mine

[shep]

i just took the thing for a thrash and it is locking all the brakes.
it starts as a slight drag and gradually builds up brake force until
the tyres are locked.

[christover1]

Do they unlock themselves if left to sit for a while?
Sounds like its not letting fluid back to master fast enough.

[royce]

see if it looks like somebody has fucked around with the pushrod on the pedal, even try backing it off when its locked

[shep]

christover1 wrote:

Do they unlock themselves if left to sit for a while?
Sounds like its not letting fluid back to master fast enough.

that sounds about right

[christover1]

I been searching.
This issue can be from water in brake lines, once hot it expands, puts pressure on brakes.
Also from incorrect fluid in brakes, causing seals to swell.
Rust on the caliper slides, and or piston can be the issue.Maswter cylinder can be an issue, too.
Shitty hoses can let fluid run one way easily, but slower on return.

[shep]

royce wrote:

see if it looks like somebody has fucked around with the pushrod on the pedal, even try backing it off when its locked

dunno. will have a look.

i was driving it without touching the brakes and it still tightened up.

[christover1]

shep wrote:

i was driving it without touching the brakes and it still tightened up.

So expanding brake fluid is a pissabolity then.

Is there a brake line too close to a hot motor or exhaust pipe?

Try draining fluid, see if it it still happens, could rule things out.

[royce]

Could also be the valve in the booster that lets it do its thing leaking and allow vaccum to bleed out on one side, try removing and plugging the hose and letting it idle or something, careful if you drive it cause the brakes will be heavy obviously

[shep]

i just made and fitted a mechanical vacuum adjuster and the brakes appear to
be working properly will go for a thrash and report back.

[royce]

shep wrote:

i just clamped some vice grips to the vacuum hose and the brakes appear to
be working properly will go for a thrash and report back.

Fixed

[shep]

fixed. woo hoo. rally time

[royce]

take the racks off before you roll it

[christover1]

shep wrote:

fixed. woo hoo. rally time

cooooool.

Now we all will sleep better tonight

[shep]

royce wrote:

take the racks off before you roll it

ok

christover1 wrote:

shep wrote:

fixed. woo hoo. rally time

cooooool.

Now we all will sleep better tonight

[shep]

well the flash vacuum thing didn't fix the problem after all. it got to the stage that
the brakes were locking on up to 5 times in a 10km drive and if i cracked a line it would have pressure in it.
even first thing in the morning the brakes would be locked on before the car was driven.

anyway i put a liter of fluid through the master cyl and lines and got a stack of water
and grit out of it and it now seems to be working properly.

[christover1]

Water would do it, it gets hot, expands and pressurises everything.
I'd flush it again after a few days, to make sure.