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Mystery rear brake cylinder

Posted: Tue Apr 23, 2013 3:09 pm
by timwilks13
Hey guys, just done a basic brake over haul, new brake cylinders, shoes etc. But in the process i came across a random brake thing that im not sure what it does nor can i find anything out about it. Basically if you follow the brake lines from the master cylinder, 2 lines run off to each of the front brakes and a single line runs off to the rear wheels, however half way down the rear brake line there is a single brake cylinder/reservoir/something im not sure of. Can anyone tell me a. what it is, and b.whats it for? it has a single line in, and a single line out so as far as im concerned its borderline pointless....?!
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Re: Mystery rear brake cylinder

Posted: Tue Apr 23, 2013 3:16 pm
by dazerede
Umm can't see what ur on about with all that mud there

Ye mine has that not sure what's the purpose of it
Mine looks a lot cleaner than urs

Re: Mystery rear brake cylinder

Posted: Tue Apr 23, 2013 4:14 pm
by Jordi
Some kind of bias valve/compensator type thingy i believe.

Re: Mystery rear brake cylinder

Posted: Tue Apr 23, 2013 4:46 pm
by suzukisteve
im with jordi, looks like the load valve bud

Re: Mystery rear brake cylinder

Posted: Tue Apr 23, 2013 7:00 pm
by Darrell
It's the D.S.P Valve

























What ever the hell that is :hmm:

Re: Mystery rear brake cylinder

Posted: Tue Apr 23, 2013 7:33 pm
by ROBBIE
Darrell wrote:It's the D.S.P Valve

























What ever the hell that is :hmm:
Digital Signal Processor using valves which give excellent sound quality hence why a lot of companies have started using them again. Wouldn't want one under a muddy SJ tho

Re: Mystery rear brake cylinder

Posted: Tue Apr 23, 2013 7:37 pm
by Jordi
ROBBIE wrote:
Darrell wrote:It's the D.S.P Valve

























What ever the hell that is :hmm:
Digital Signal Processor
Digital. I dunno Robbie. If its digital mine is definately broken.

Re: Mystery rear brake cylinder

Posted: Tue Apr 23, 2013 10:19 pm
by Darrell
Well I had to find out what it is, so
It's basically a valve to stop the rear end from locking up under heavy braking.
As far as I can find out its fitted to some sj410's and the LWB sj413.
Its a "Deceleration Sensing Proportioning Valve"
If your sad enough like me and want to know more http://www.google.co.uk/patents/US4194792

Re: Mystery rear brake cylinder

Posted: Tue Apr 23, 2013 11:06 pm
by Edweird
In leyman's terms: It's like a REAAALLY primitive ABS for the rear axle.

In Yeller-belly: It's a fing whot keeps yer back whirlies from stoppin' when yer slam yer anchors on.

Re: Mystery rear brake cylinder

Posted: Tue Apr 23, 2013 11:47 pm
by Pugsley
Important that when bleeding the rear brakes that you bleed this valve also - if you clean it up I'm sure you will find that it has a bleed valve. Be extremely careful when undoing the bleed valve as it is pretty weak and it will be corroded in - from memory it's an 8 mm spanner size. I had to completely remove mine and apply some "scientific" heat to to the bleed valve to undo it and even I nearly snapped it off. The problem with heating it is that the valve inner components have rubber seals which can be destroyed using a blow torch - I stripped the innards out before heating it and it's just as well I did as it was siezed solid.