Brake master cylinder

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Brake master cylinder

#1 Post by new to this »

Hi

how do you tell the difference between the single and tandem brake master cylinders ?

Am i right in thinking tandem means duel circuit,apart from the brake master cylinder what else do you need to convert

thanks Dave
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Flyfisherman
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Re: Brake master cylinder

#2 Post by Flyfisherman »

PDWA Valve

http://www.rimmerbros.co.uk/Item--i-RTC2525

some one on the forum may have a spare

paul
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xvivalve
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Re: Brake master cylinder

#3 Post by xvivalve »

You are correct, the tandem system has a dual circuit pipework.

The single system master cylinder has a vertical cylindrical reservoir on which the cap is the same diameter as the reservoir beneath and only a single pipe issuing from the top of the aluminium cylinder, whereas the tandem master cylinder has an irregular shaped more horizontal reservoir with a cap smaller than the overall size of reservoir and two pipes issuing from the side of the iron cylinder.
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Re: Brake master cylinder

#4 Post by Carledo »

Flyfisherman wrote:PDWA Valve

http://www.rimmerbros.co.uk/Item--i-RTC2525

some one on the forum may have a spare

paul
You don't actually NEED one of these, the factory included it as a way of telling you if you had lost pressure in 1 circuit of the braking system, as if only having half a brake pedal wouldn't do that for you! In practice,they make the brakes a pig to bleed, have to be set up by an awkward additional bleeding process and often put the light on when no fault is actually present. I converted the Carledo brakes to dual circuit and installed this because it was on the original system. After a year or two of fiddling with it on and off, to try and make it reliable, I gave up and binned it. The only noticeable difference is that I can now do a complete brake fluid change in minutes instead of hours! Oh and no annoying intermittent red light on the dash!

Steve

All you actually need to convert to dual circuit is the master itself, a couple of pipes and a 3 way union and an inline joiner (or a PDWA if you must) to replace the original 4 way junction on the bulkhead. Note, the PDWA also (for some unknown reason) uses an almost unique coarse threaded imperial union which is almost impossible to get - i've tried!
'73 2 door Toledo with Vauxhall Carlton 2.0 8v engine (The Carledo)
'78 Sprint Auto with Vauxhall Omega 2.2 16v engine (The Dolomega)
'72 Triumph 1500FWD in Slate Grey, Now with RWD and Carledo powertrain!

Maverick Triumph, Servicing, Repairs, Electrical, Recomissioning, MOT prep, Trackerjack brake fitting service.
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Magenta Auto Sprint
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Re: Brake master cylinder

#5 Post by Magenta Auto Sprint »

I have a spare PDWA valve thing if you are interested, I just have to find it.

Malcolm
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Re: Brake master cylinder

#6 Post by xvivalve »

Both types of cylinder, refurbished and sleeved in stainless steel available from Club spares.

Whilst on an exchange basis, if you send one type, but want the other, then that is OK.
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Re: Brake master cylinder

#7 Post by new to this »

Carledo wrote:
Flyfisherman wrote:PDWA Valve

http://www.rimmerbros.co.uk/Item--i-RTC2525

some one on the forum may have a spare

paul
You don't actually NEED one of these, the factory included it as a way of telling you if you had lost pressure in 1 circuit of the braking system, as if only having half a brake pedal wouldn't do that for you! In practice,they make the brakes a pig to bleed, have to be set up by an awkward additional bleeding process and often put the light on when no fault is actually present. I converted the Carledo brakes to dual circuit and installed this because it was on the original system. After a year or two of fiddling with it on and off, to try and make it reliable, I gave up and binned it. The only noticeable difference is that I can now do a complete brake fluid change in minutes instead of hours! Oh and no annoying intermittent red light on the dash!

Steve

All you actually need to convert to dual circuit is the master itself, a couple of pipes and a 3 way union and an inline joiner (or a PDWA if you must) to replace the original 4 way junction on the bulkhead. Note, the PDWA also (for some unknown reason) uses an almost unique coarse threaded imperial union which is almost impossible to get - i've tried!
yes its one of the threads on the PDWA that is a different thread like you dont know what thread it is
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Re: Brake master cylinder

#8 Post by new to this »

Magenta Auto Sprint wrote:I have a spare PDWA valve thing if you are interested, I just have to find it.

Malcolm
thanks for offer,but i have a spare

Dave
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Re: Brake master cylinder

#9 Post by new to this »

xvivalve wrote:Both types of cylinder, refurbished and sleeved in stainless steel available from Club spares.

Whilst on an exchange basis, if you send one type, but want the other, then that is OK.
Thats handy to know,about the stainless steel sleeved. Cylinders

Thanks Dave
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