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 Midget and Sprite Technical - Binding Rear Brakes

This is happening on my Morris, but same thing.

Both rears are sticking on, sometimes releasing, sometimes not. When I got home yesterday after a two-mile trip, both were hot - the nuts not comfortable to touch.

I've tried to get a drum off, but with the shoes free it will not come. Perhaps welded to the half-shaft endplate.

Quaere - why both at once, if it's a cylinder or spring? Why not fronts too, if it's a master cylinder problem?

There's a servo fitted.
Nick and Cherry Scoop

Nick,
maybe it's the rubber hose connection to the rear brakes. I am sure you have heard the tale before, but the brake flexible hoses sometimes deteriorate internally such that the lining colapses and then they work like a one way valve. They allow fluid through under pressure when you apply the brakes, but don't then allow the fluid to flow back the other way to release them. Brakes get progressively tighter every time you press the pedal.

The fact that in the Sprite, there is a single flexible hose feeding both back brakes would explain why it the rears, and both of them at the same time. I don't know if the same arrangement applies to the Moggie, but probably.
Guyw

What Guy says.

Try loosening one of the bleed nipples on the rears and see if they release.
Dave O'Neill 2

Handbrake compensator sticking?
I've had wheel cylinders gum-up and stick in the past but not both at the same time
Simon Wood

I found mine were binding on the frog due to the returning springs being incorrectly installed causing the shoes to kick over and jam on. which meant the cylinders couldn't slide properly etc

Fixed now but certainly caused much head scratching
R Williams

Thanks All. Guy, I've renewed both cylinders, pipes, shoes etc. in the last couple of years, but had forgotten that flexible which serves the three-way union on the axle.

That sounds favourite. Any preference between rubber and metal braided?
Nick and Cherry Scoop

Nick, I use metal braided. But they have been on a long time now and although I don't think they suffer the same degradation issues as the rubber ones, they apparently don't last indefinitely and I should probably replace them.

Given the reported issues with currently avaiable rubber seals etc, I would wonder if this quality problem extends to brake pipes too at the moment.
Guyw

The metal braided hoses offer only aa little extra protection to road debris, but are otherwise a service item like all brake hoses. They have the huge disadvantage that you can't see what state the rubber hose is actually in.
dominic clancy

There are Two types of braided hose, rubber lined and Teflon lined. When I was working on aircraft, the rubber lined ones had a definite life, whereas Teflon lined ones were "on condition", which means they only had to be replaced if they looked to have been damaged.
Teflon hoses have been around a long time now, so the need to replace them just because they have been on a certain time no longer applies.
My midget hoses from Merlin Motor sport are Teflon.

Dave
Dave Barrow

Considering the dubious quality of any rubber products now available for our cars, I certainly feel more assured as to quality by fitting these, rather than something made in a Chineese shed !

http://goodridge.brakes-hoses-fittings.co.uk/
richard boobier

HEL are an alternative to Goodridge and are usually more reasonably priced.
David Smith

Thanks very much. We're on holiday next week, so I'm investigating now and ordering before we go. The couriers round here are used to leaving things in the greenhouse.
Nick and Cherry Scoop

Nick,
It may not be the hose, but the check is as Dave O'Neill suggested. When the brakes are binding after a short journey, try just slackening one of the rear brake nipples slightly. If the system is pressurised because of a faulty flexible hose the pressure will escape and the brakes release.
Guyw

I thought mine were ... self healing /repairing

ive noticed this past week that my rear brakes are also working alot better then they used to... i havent messed with them but they are improving ... to my knowledge there not getting hot or sticking and ive got the stainless steel hoses and not the old rubber brake hose

prop
prop

Even if it's not the problem, I think a spare hose is a good thing to have on the shelf - or rather, in an airtight, lightproof box.

I know this profligacy goes against the grain for you, Guy.

(I never thought I'd meet someone who would repair a piston cup by sculpting a new section)

Thanks everybody.
Nick and Cherry Scoop

This thread was discussed between 09/06/2016 and 12/06/2016

MG Midget and Sprite Technical index

This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.