Brake pressure adjuster

[fixerupper]

Hi anyone now anything about the thing that adjusts the brake pressure when you have a load on a truck ...I've been doing firewood for the last week or so ...I go off in the morning in me Mazda b2500 and the brakes work normaly ...prune a load of trees and load the truck with a ton or more fire wood drive to the yard few a few muddy puddles unload the wood ...drive home empty and the brakes on the rear lock up if I breath on 'em .. scary on wet tarmac ..slowly it kind of gets back to normal ...is it possible that the muddy water is jamming up the mechanism or is just slow to react ...squirt with WD 40 or a hose ..? jeff....

 

[Rocketman]

Mech is probably jammed from corrosion/muck. As you say it's a matter of working it loose again with lots of oil until it moves freely. Did it myself last year. It's actually a MOT failure if it's not moving freely but sometimes they miss it.

 

[dan.taylor.1]

As above it'll be seized and sticking open after the loads removed.

 

[CRB]

As above. There is not really a mechanism, just a spring acting on the lever, it does sound like the piston/rod is binding which is probably due to corrosion, usually after a long time of not moving due to lack of loading and unloading.

Mine is still working, which is just as well, no longer available and not easily rebuildable.

 

[CompoSimmonite]

If the rear flexible brake hose has collapsed inside then it could be retaining pressure if the valve working OK.

 

[roofman]

I have to keep mine well lubed up with WD40 during the winter months (road salt ect) or it plays up...my truck is a Nissan Cabstar. These devices could,nt be in a worse spot too.

 

[Fintray]

My wife's last Suzuki Wagon R had one and it failed the MOT because it was stuck, did just what the guys said above and all ok. Her latest one no longer has that valve.

 

[gordon stephenson]

I kept mine well wrapped with Denso tape on the land cruiser, Always kept it working nicely. Caught me out once tho' when bleeding the system after changing a couple of brake pipes. The limiter had a bleed nipple i hadn't spotted.

 

[wookie]

As above. There is not really a mechanism, just a spring acting on the lever, it does sound like the piston/rod is binding which is probably due to corrosion, usually after a long time of not moving due to lack of loading and unloading.

Mine is still working, which is just as well, no longer available and not easily rebuildable.

What's your vehicle ? as I've a MK3 Hilux and I've done the load adjuster on it, that one is dead easy to strip and rebuild.

 

[Hitch]

I smarm a bit of grease over mine every so often now.

Had a seized one on an old van, the spring wasn't attached either. Failed on the spring not being attached....
Put the spring back on, and it'll pass he said.

 

[Bill Edwards]

Plenty of thin oil to get in and free it off, work it a lot until it's nice and free.
Then cover the mechanism in good, thick grease to keep water and dirt out.

I've never looked at the type used on the Mazda B2500 (the one at work has been no trouble) but they're normally just a simple lever moved by a spring which changes as the suspension is loaded.
Plenty of lubrication is needed!

 

[fixerupper]

Thanks for all the replys guys , I'll get the hose on it in the morning to wash the clay mud of it and then when its dry , oil it up ......On the trip to my yard I have to drive though a deep muddy puddle that fills the track for about 6 or 8 metres this time of year ... this clay stuff sets rock hard ...maybe it might be an idea to make a cover for the mechanism to keep this from happening every winter ...jeff...

 

[CRB]

What's your vehicle ? as I've a MK3 Hilux and I've done the load adjuster on it, that one is dead easy to strip and rebuild.

VW LT28 1989. it is the 'same' as a DAF part but not having much luck there either. Our German chums LT-Fruende have a detailed rebuild write-up, and one of the BrickYard chaps has put a 1H0612151C from various VW/SEATs on. Works a treat.

 

[roofman]

Thanks for all the replys guys , I'll get the hose on it in the morning to wash the clay mud of it and then when its dry , oil it up ......On the trip to my yard I have to drive though a deep muddy puddle that fills the track for about 6 or 8 metres this time of year ... this clay stuff sets rock hard ...maybe it might be an idea to make a cover for the mechanism to keep this from happening every winter ...jeff...

Wrap a bag around it with cable ties after lashing it with grease