front disc residual valves.

vwo60 Veteran Volks Folk

2,036 posts · joined Feb 2007 · 12 Jan 2013, 9:28 pm

#939018

I have just installed my new front disc brakes using a set of four spot calipers, the rears are a set of CB performance rotohubs, i have not been able to get a consistant brake pedal, after it was bleed the pedal was good but then after some use it began to increase in travel, i had a look at the calipers and there was no drag on the rotor's and the pads had moved away from the disc's, i ordered a set of 2LB residual valves and installed them today, what a difference, the brakes now have a small amount of drag but there is no increase in pedal travel with use, the pedal has good feel and does not change, if you are having a issue with to much travel on a disc brake conversion a larger diameter master cylinder is not necessarly the answer, if the pads are moving away from the rotor's this could be the fix.

vlad01 Compulsive Aussie Vee Dubber

4,270 posts · joined Jun 2010 · 17 Jan 2013, 2:39 pm

#939496

where did you get them from?

71 notchback,
Past owner of, 70 NB, 73 SB and 72 FB TLE

68AutoBug Beetle Restorer - Experience over 138\% - YIKES --

11,654 posts · joined Aug 2002 · 17 Jan 2013, 3:56 pm

#939503

on VW [ate etc[ disc brake master cylinders there are residual valves to keep slight pressure on the front calipers.
the residual valves screwed into the top of the [disc] master cylinder and the two front pipe fittings screwed into them.

on USA front drum brake master cylinders [no beetles had discs in the USA] the pipe fittings screwed straight into the master cylinder and were a different size so the two different master cylinders couldn't be used by mistake..

as the pipe fittings for drums didn't fit the disc master cylinders with or without the residual valves...
[Only Karmann Ghias had discs in the USA]

LEE

- Helping keep Air Cooled VWs on the road - location: SCONE in the Upper Hunter Valley - Northern NSW 320 kms NNW of SYDNEY---

vwo60 Veteran Volks Folk

2,036 posts · joined Feb 2007 · 17 Jan 2013, 6:47 pm

#939518

Wilwood make a 2lb and a 10lb residual valve, the only master cylinders with residual valves that i have seen on a vw was the drum brake 74 poverty pack beetle, i have never seen them on a disc brake master cylinder, live and learn.

68AutoBug Beetle Restorer - Experience over 138\% - YIKES --

11,654 posts · joined Aug 2002 · 17 Jan 2013, 7:55 pm

#939528

vwo60 wrote:Wilwood make a 2lb and a 10lb residual valve, the only master cylinders with residual valves that i have seen on a vw was the drum brake 74 poverty pack beetle, i have never seen them on a disc brake master cylinder, live and learn.

Hi

Looks like I got it the wrong way round as it was a beetle owner in the USA having the residual valve problems..
His pipe fittings were the wrong size to screw into His New master cylinder..??

so, the drum brakes must have the residual valves...

as the disc calipers are designed to keep the pads close to the discs [self adjusting] ...
even as the pads wear..

I stand corrected... cheers

LEE

- Helping keep Air Cooled VWs on the road - location: SCONE in the Upper Hunter Valley - Northern NSW 320 kms NNW of SYDNEY---