No brake pressure

The rubber o-ring in the caliper won't play well with grease. The grease causes the rubber to swell up. You will probably have to replace the o-ring.
Leo
 
Bleed nipples are typically a little loose but not wobbly. There are nipples made with check valves that lock-in when tightened and really do make bleeding pretty easy. There are also GM transmission parts (check ball capsules and vacuum hoses) that can be manipulated for simple one man (or any of the other 56 "woke" genders) brake bleeding use.
john
 
why pay Geofs a fortune for a couple of nipples............the local engineering shop would be cheaper and you can compare the old to new or take a caliper with you..........
 
Geoffs sells them for $2.90 ea. SuperCheap Auto have them but they are $6.90 ea. AutoBarn wants $6.99 ea. and I can get a set of "speed bleeders from Amazon for $22.67 (USD) + 8 bucks delivery. Pro Bolt will sell me a stainless one for $6.96. Size for all is 10mm x 1. Quite a range of prices for a relatively small item. My local engineering shops want to rebuild my motor not sell me bleed nipples - inconsiderate. The one's I got from Geoffs should be right but they do seem loose in the thread until tightened. Perhaps I'm nitpicking. I'll buy one from SuperCheap on Saturday and try it out.......but $7.00 - can't afford to retire until I finish the XS!
 
The banjo bolts may be a 10mm x 1 but I don't think the bleed nipples are, they're much smaller than that.
 
Geoffs sells them for $2.90 ea. SuperCheap Auto have them but they are $6.90 ea. AutoBarn wants $6.99 ea. and I can get a set of "speed bleeders from Amazon for $22.67 (USD) + 8 bucks delivery. Pro Bolt will sell me a stainless one for $6.96. Size for all is 10mm x 1. Quite a range of prices for a relatively small item. My local engineering shops want to rebuild my motor not sell me bleed nipples - inconsiderate. The one's I got from Geoffs should be right but they do seem loose in the thread until tightened. Perhaps I'm nitpicking. I'll buy one from SuperCheap on Saturday and try it out.......but $7.00 - can't afford to retire until I finish the XS!

certainly a big difference in pricing there..............still i think if the more expensive nipples do seat properly your life has just benefited for the sake of $5.00...........at least you wil get to retire
 
Dismantled the calliper. Took off the grease, cleaned the seal with Kerosene and Silicone spray and put it back together. No pressure. Bit the bullet and pulled the MC to pieces. Here's the piston assembly (pic 1). This is the original that came with the MC. I now recall that when I opened the Bangood kits, they seemed to be thinner and longer. the original seemed to be in good condition and was assembled as per 5T's photos. The spring is also right way round, (small end on piston). All looks fine to me but could reusing the old piston and rubbers be the cause of my troubles?
 

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Proper brake lube.... on caliper slide sleeve..contact caliper points to brake bracket and back of pads... brake juice toCaliper rubber.jpg sent the piston in bore... photo... top is stock.. bottom after fork oil got to it….
While bleed'd the system.. I've found once in a blue moon... that I have to pump and open the banjo bolt at the master.. and it did wonders.. trapped air..? I wrap a rag around this area to prevent spray on my paint work...
 
The only cleaning solutions for brake fluid containing systems are: WSW rinsed with clear water, clear water or the correct brake fluid. There are reasons that master cylinders state which type brake fluid to use. Now for the story, A few years back in the '60s I drove a MGB and had hydraulic clutch issues. I purchased the rebuild kit and rebuilt both master and slave used kerosene for cleaning and fresh, plain old brake fluid, the master cylinder stated use only Girling approved brake fluid. Guess what, the rubbers in both cylinders turned to GOO in 2 weeks and failed. Rebuilt them again, thinking must be bad rubbers. Same procedure, same result. Did some studying and got some education, brake fluids are not the same, they absorb water and are not compatible with petroleum based solvents. Rebuilt the cylinders again using proper solvent WSW rinsed in water, the problem never reappeared. Using the correct solvents, lubricants and fluids in your brakes can save your life.
john
 
Fixed the rear brakes. Disconnected the banjo at the calliper and filled the reservoir behind the piston. Used a fine diabetic syringe to inject brake fluid into the line. Checked that the line was being pressurised when I hit the pedal - it was. Hooked everything up and bled the system. Got brake action in about ten minutes. Obviously I used my own combination of the procedures outlined here by several members so..... thanks gentlemen.
Didn't have much vertical movement in the pedal. I adjusted the plunger rod at the master to allow a little more play and achieved about an inch before the wheel locks up. Is this acceptable? Also, I get a clicking noise when I rotate the wheel and hit the brake - seems to come from the mounting bolt at the top of the calliper assembly. The nut is tight but there is still free play in mounting bracket. Is this normal?
I am waiting for the new front master kit. I probably could have used my original but, it s better to be safe...etc. I will use the same technique with this one and see if I can get it to function.
I had cleaned up the master previously and repainted it. The paintwork suffered from brake fluid blemish so I took it all off again and will leave it unpainted. Funny how some experience seems make the job so much easier. I now allow for two attempts at any job. One to see it in "hands on " practice and one to get it right. I know, I should measure twice and cut once but....what the hell!
 
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