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 - Quality brake cups



The master cylinder was sweating and there was a black massive sludge on the bottom although I change brake fluid every 1.5 years. I ordered new main 7/8 cylinder cups from M..s but was not impressed by the quality; rough finish not very elastic. It took AH Spares a week to deliver but their cups look much better.
The old cups lasted only 7 years (DOT 4 brake fluid). When I used DOT 5 (silicone) they lasted more than 10 years. Is it the quality of the rubber or the brake fluid? Is 7 years normal? Should I have used DOT 3?

Flip
Flip Brühl

I suspect its the quality of the rubber. Dot 4 has a higher boiling point than Dot 3 so should not be the problem. I don't know about Dot 5. You could try soucing original stock. Powertrack Brakes are a good supplier.
Bob Beaumont

My question is: Do I have to change the rubbers in the calipers, wheel and clutch cylinders? it is a single brake /clutch system. One leak is enough...
Flip
Flip Brühl

I haven't experienced the problem with the rest of the hydraulic system using NOS seals. I change brake fluid every 2 years or so. Did you use aftermarket seals in the calipers/brake/clutch system.

Bob Beaumont

Bob,

I do not know where I bought them.I suppose Limora. The calipers, clutch and wheel rubbers are from C & C special parts. I trust them but for how long?
Flip Brühl

I suggest you really clean and then renew the rubbers in the master cylinder and bleed through with new fluid.

I would also inspect the brakes and clutch to see if there was any sign of a weep or dampness. I don't know C & C so cannot comment on the qualiry of the product.

If you want to change to Dot 5 you will need to remove every trace of the Dot 4. This includes fixed brake lines, all the rubbers in the brakes and clutch as silicone will not mix with normal fluid and is easily contaminated.
Bob Beaumont

About 17 years ago, after a circuit day at the TT circuit in Assen with the Sprite I encountered serious fading. So I went from silicone to DOT 4. and from front drums to disc brakes. I 'll stick to DOT 4. I changed the master rubbers and I'll control the slaves. What is the average time that you guys change brake rubber?

Flip
Flip Brühl

This thread was discussed between 16/11/2020 and 18/11/2020

MG Midget and Sprite Technical index

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