MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGB Technical - still have brake problem !!

hi, again
79mgb

i still cant bleed the brakes, no brakes.

i have replaced the rear wheel cylinder kits, both sides along with new shoes.

i have completely replaced all the rubber innerds of the brake master cylinder and the failure switch
(pwda ) and filled with new fluid.

but when i pump on the brake pedal to bleed, i have help so i can regulate the flow, no brake fluid ever comes out.

since i am pumping with the engine off, i dont think
the problem is in the servo assembly ??, yet.

please help, tell me what i have forgotten to do.

thanks

john





john sutter

John,
try with the engine running. I haven't worked on a late split circuit system but have been studying the drawing and I know there should be a direct connection from the pedal to the master cyl but I just cant see it...
With the engine running you at worst make the system the same as when in operation.

Then I think I would be tempted to loosen the pipes on the master cyl one at a time to see if you can get fluid to flow from there. If it flows move on to bleed the front brakes (near side first). Once these are flowing, crack the pipe to the rear at the joint which should be under the floor just in front of the cross member. When you get fluid moving there it should be straight forward to move on to the rear wheels!

Let us know how you get on.

MGmike
M McAndrew

John have you tried bleeding with the brake fail electrical switch removed, as this is necessary with a duel system to get fluid to the wheels that have been disturbed (the brake fail has detected loss of rear brakes and will not reset . Dont replace until you have achieved a hard pedal. Denis
Denis4

You really need a continuous flow method like the gunson's EeziBleed. With a lot of air in the system the pedal will simply pressurise that, releasing the pedal will release the pressure and maybe pull fluid back, unless perhaps you hold the pedal down for a long time each time.

I know you can't bleed systems with the remote servo with the engine running, because as soon as the servo comes into play it closes off the port between the master and the wheels, don't know about the integral master. In any case the engine shouldn't have to be running. Have you checked fluid is leaving the master? Run pipes from the outlet ports back into the reservoir.
PaulH Solihull

hi 79mgb
i really screwed up !!
when i reassembled the brake master cylinder, i got the stop pin in incorrectly, so it essentially stopped all internal movement. so, no wonder i couldn't bleed the brakes, nothing pumped !
thats not bad enough, i can't get the stop pin out.
i'm really depresed

john

john sutter

John, we've all been there. Depression is a state of mind that can be rectified by drugs or money! In this case money for a replacement master cyl is a small price to pay for education!

I never recommend drug's but as you are over the pond you might want to check with your therapist before you spend money....... local joke....

MGmike
M McAndrew

John
Will you ever make that mistake again?? I think not.

Just consider this to be a small price to pay for the enjoyment you undoubtably get most of the time

John
John Minchin

This thread was discussed between 16/10/2011 and 22/10/2011

MG MGB Technical index

This thread is from the archive. The Live MG MGB Technical BBS is active now.