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Wanted: Brake Master Cyl. Repair Kit for Daimler DS420

volunteer

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This is a 1971 right-hand drive limo. Master cyl. is at steep angle and is physically 7 inches in length. The mounting flange is 3.25" hole to hole and the fluid inlets on top. Front (closest to booster) inlet is a flange about 1.125" hole to hole. The front seal is approx. .872" dia. with a .435" hole and rear seal is much narrower and has an O.D. of about .832" and inner hole about .50" - - I say approx. or about because seals are still as installed. These parts likely fit other Daimler or Jag master cyls. but I have absolutely no info to search. I will need, at very least, the two above mentioned seals and at the very most, the complete master cyl. Can anyone point me in right direction? Please and thank-you.
 
That would be 'Google', right? Missed it on Bing. Thanks. EDITED: Okay - ad states 0 available and pictures inconclusive and price total in CDN funds close to $80. This is from J.G.J.S. - I am familiar with them but I will keep searching.
 
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so yes I goodled it and didn't notice that it was out of stock. - will google next time gor sure :D

silliness aside, the part numbers and interchange are often useful. (This is how I figured out my Vauxhall rebuild kit was also a Lotus kit)

Google the part number and


which seems also to match the ebay description of alternate uses
 
Some have better luck searching than others anyone better than me. Thanks much for your help (and humor). Those little parts look like the real deal. I am familiar with Moss - and also with B.P.N.W. (Oregon). Price okay, considering what entire cyl. would cost.
I should also mention that the first kit (ebay) and the Moss kit have identical part numbers, but, pictures are not the same. I see a lot of this during my 'travels'.
 
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I should also mention that the first kit (ebay) and the Moss kit have identical part numbers, but, pictures are not the same. I see a lot of this during my 'travels'.
That frustration I am more than aware of - same deal with the vauxhall and other parts
 
keep us posted
 
Well, I installed parts in the order I removed them - or so I thought - but fluid will not enter the rear calipers. Something has to be missing or out of order. Is there any chance of a link to a diagram of the cylinder internals?
 
not sure we can help with a diagram, but,

1) is there a rubber hose (or two) leading to the rear calipers? These tend to perish internally while looking fine outside, if you haven't already replace them.

2) is there a splitter (proporting) valve - don't know what it is actually called, but, it is like the picture. I can't tell you how filthy mine was. You should also be able to blow out the brake lines with air.

3) you should be close - now it is just a matter of section by section.

1655170926809.png
 
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Thanks for all the info and suggestions. Pretty sure rear lines all clear as brakes were working well a year ago. Car sat for 22 years and had fluid change (and bleeding at all four calipers) only two years ago. Just age and fatigue allowed the cup seal at front flange area of m.c. to lose enough tension that allowed fluid to gravitate out (into booster and on to ground). The way (m.c.) is now, there is no rear spring (as newer mid-80's version depicts). Something not right. I will remove the affected outlet tubing (at m.c.) and start from there. Diagram anyone?
 
I have a hard copy service manual from about 1985 but internals not same as '71. The 1968 diagrams also different. Once I confirm the rear system all clear, I may be looking at replacing entire M.C. - but that could initiate a whole new series of problems.
 
...

2) is there a splitter (proporting) valve - don't know what it is actually called, but, it is like the picture. I can't tell you how filthy mine was. You should also be able to blow out the brake lines with air.

....

View attachment 78916
The item pictured is a Pressure Differential Warning Actuator (PDWA). Its function is to warn if either the front or rear brake circuit loses pressure. If one of the circuits loses pressure the small shuttle piston seen between the PDWA body and the end cap is shifted and the pin on the switch rides up the ramp off of the shittle piston's small diameter area triggering a warning light. I don't specifically recall those on early XJ models. I know they were fitted to the Series III E-Type as well as some late Seriies II cars but I seem to recall the configuration on those being different with the switch located off to the side as opposed to on top. That configuration is more in line with I know was fitted to the TR6.
 
Thanks Tybalt - I tend to get stuck with the only slightly less technical 'thingamabob' trying to remember what everything is called. :ROFLMAO: Seriously though, mine was beyond filthy when I took it apart. Thanks again for the name. :cheers:
 
Glad to help. Before Moss and some others started offering a TR6 PDWA repair kit, mine was leaking. I picked up some AS568 (size spec)-008 (specific size) in an ethylene propylene material from McMaster-Carr. The other thing I thought was trick but also made finding some of the fittings for the flared lines difficult is that the front and rear use different size threads on the tube fittings so you can't mix them up even though both circuits use a 3/16" or -3 tube size.
 
Glad to help. Before Moss and some others started offering a TR6 PDWA repair kit, mine was leaking. I picked up some AS568 (size spec)-008 (specific size) in an ethylene propylene material from McMaster-Carr. The other thing I thought was trick but also made finding some of the fittings for the flared lines difficult is that the front and rear use different size threads on the tube fittings so you can't mix them up even though both circuits use a 3/16" or -3 tube size.
Very aware of the different sizes, especially with my Vauxhall!
 
not a diagram but there seem to be manual options here > Daimler DS420 Service Manual AKM9135 Ed. 4 (1990) <
Time to Update. One week ago I removed the MC and got back inside. There is a secondary spring that takes some finesse to remove. Also, the smallest rear seal, which I did NOT initially remove was severely swelled and distorted. It came off in pieces. With new one installed, everything went back together and this time I had fluid flow from rear inlet to outlet - and ultimately to rear calipers. Result? Pressure to all four calipers. I am pleased. Drove car on Saturday for my daughter's graduation functions. Noticed some 'click-click' sounds upon initial acceleration from the rear (outboard) axle area. CV type joints?
 
no idea about the sounds - but congratulations!
 
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