Mk1 rear disc brake problem

[Memphis]

Does anybody know what this is and if it’s adjustable


My mk1 has rear discs but locks them up all the time.

[Peter Jones]

That's a proportioning valve off a later golf.

Normally that self adjusts with suspension movement, yours has been locked in place.

You should be able to adjust it to the fully loded position and change the brake bias. Looks like you're up for some fiddling to sort it out though.

Change the length of that threaded rod. I'm not if it needs to be longer or shorter.

Pete

[Preen59]

You'd be better off to put some adjustable inline bias valves in mate. Smaller and less complicated.

[Memphis]

Thanks for the reply's, so if i put some inline valves can i leave this setup as is?

[Memphis]

Also noticed the rh rear spring touching tyre slightly, at a ruff measurement the rh wheel is sitting 10mm inward compared to the lh
I still have even wear on the tyre. I'm thinking the trailing arm has been bent? any ideas
Thanks in advance

[Jarred]

is it just the photo or is that spring bent?

[ontarv]

it could be just your bushes but could be bent unless you have
owned it from day dot its hard to know what could of happened
and to answer jarred's Q looks like they are king springs and kings
don't sit properly on the shock seat mine are the same

[roccodingo]

That proportioning valve is mounted incorrectly, From memory ( rusty) the valve block with the hoses should attach to the body, the link then goes between the valve body to the bolt on lever that is fixed to the rear axle. As the axle moves due to load or suspension travel, it moves the lever on the valve body, regulating the brake bias.

As for the difference in rear wheel position, you can move the rear axle pivots slightly to help correct the alignment, otherwise could be bent stub axles, or bent beam...

HTH, but get it sorted !!!

[Memphis]

Yes they are dirty king's, need new shocks also so will be replacing the whole set, any recommendations? Was thinking KW v2 but don’t know where to buy?

The spring has bulged outward but i think the pic makes it look worse, hopefully nothing serious is wrong and its only the king springs

So with this brake regulator is there anywhere to properly mount it on a mk1? im guessing it's off a mk2 or 3, any pics would be a great help!

Thanks for the help guys

[Oneofthegreats]

That proportioning valve is doing absolutely nothing.

It's locked in one position, bieing the block is solidly mounted to the rear arm & the lever is also mounted solid to the rear arm.

The main block should be attached under the body on the LHS & the actuating lever should be connected to the rear trailing arm by a spring.

Also on top of that, with running rear disc's you should also be running the 16V proportioning valves at the master cyl.

I've been down this road before & the standard valve isn't enough restriction for the rear disc conversion.

I also found out that it is unroadworthy & doesn't comply to ADR's (only to people in the know!) to run rear disc conversion on a mk1 without the 16V proportioning valves.

If I was in your position, I'd piss that valve block off & just fit a aftermarket inline adjustable proportioning valve. Much easier & also much cheaper than chasing down some proper 16V item's.