MG MGB and MGB GT Tech Talk
well at least i searched the library first. i'm going to rebuild my calipers. a few questions.
1- can air pressure be used to remove the pistons? i have no fluid in the lines.
2- how necessary or helpful is the tool moss sells to put these things back together?
3- where can you find disc brake lubricant or will brake fluid work?
4- any tips i missed?
5-thanks
If you want to save yourself the work here is a set for sale on e-bay.
# 130157726168 starting bid $8.50 for the set.
See PM on the subject...I used air pressure and it worked quite well.
I've rebuilt a couple sets of calipers, but it was about 20 years ago so not very fresh in my memory.
I used air to get them apart. Be careful about your fingers!
Didn't use a special tool, and used Girling grease as an assembly lube.
1) Gentle air pressure works fine. Don't use too much - they will come out at high speed and you might be injured.
2) I can't imagine why a tool is needed to reassemble - I found rebuilding the calipers pretty straightforward.
3) You should definitely use brake fluid as a lubricant for all internal parts. Lubrication of external points that rub is best done with silicone brake grease - available at any automotive supply store.
4) Make sure you don't interchange the left and right calipers. They will go on fine but you will never get them to bleed. The bleed valve must be at the top.
Moss sells brake lubricant for assembly of brake seals, it is best to use lube if the car is going to sit for some time before driving. See page 54 in the current Moss catalog part 220-440 Brake Lube Sachet. You may be able to find it at NAPA. Years ago all good repair kits for import car came with a small packet of seal assembley lube.
Clifton
I used a small block of plywood to give the ejecting piston a bit of a break rather than have it smash into the opposing piston or body.