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 TD TF 1500 - I am not crazy!

Well, I rebuilt my resleeved master cylinder 3 times, and it failed each time. It would leak like crazy, leaving brake fluid everywhere. The first time, I thought it was because it had sat dry for 1 1/2 years while I was working on other things. The second time was a mystery, but when I pulled it apart, I discovered lots of grime and grit inside. After the third rebuild failed, I gave up and ordered a new MC from Moss. I installed it this morning, but I really wanted to find out why the old cylinder failed.

I pressurized it and noticed something I hadn't noticed before in the previous three rebuilds. It was bubbling on the edge, between the casting and the sleeve! There was actually enough of a gap between the sleeve and the casting for air (and brake fluid) to escape! All of this time I had thought I just been incompetent in my rebuilds.

Apple Hydraulics is going to get a call Monday morning, and it's not going to be a happy call. Although their resleeve job looked pretty, it wasn't functional at all. I hope they will at least redo the job, but that won't make up for all of the frustration, lost time, and the quart of brake fluid that ended up on my garage floor.
Mark Barrington

Mark - If you were using silicone fluid, Apple probably won't do anything for you as they specifically warn against using silicone, since it will leak past the smallest imperfection (like synthetic oil). We have a gentleman here in Washington state who threads the sleaves and uses lock tite when assembling them so the cylinders can be used with silicone fluid. Good luck - Dave
David DuBois

mark, i have converted a few cars over to silicon fluid and have not had any problems. i have never used apple, but if they have a restriction in their warranty about silicon fluid, use another rebuilder. it is not the fluid. tom
tm peterson

I had my master cylinder sleeved by White Post in 1984, have used silicone since and no leaks! Your problem seems to be Apple.
Don Harmer

I originally filled with the Valvoline Synthethic version of DOT 4 brake fluid. I've used it before with no problems. After it started leaking after the first rebuild, I switched to regular DOT 4 fluid.

It's possible that the synthetic fluid caused the problem, and the original leak 'cleared a path' for for the leak to get worse. In any case, after the third rebuild, it was bad enough to visibly bubble between the casting and sleeve whenever I appplied finger pressure to the brake piston. I suppose I never noticed that before because I had gotten thing really clean before rebuilding. When it was soaked in brake fluid, the leak was really obvious.

I've only had Apple do two things for me, ever, and both of them were sloppy jobs. I hate to run down anyone who works on these kinds of cars for a living, but this doesn't seem to be acceptable work to me. I don't think I'll ever use them for anything again.
Mark B.

I had similar silicon leak with a sleeved front wheel cylinder from White Post. They also frown on silicon fluid. Some years back a shock Apple rebuilt started leaking- at least 2 years out of warranty. They repaired for free, so I couldn't complain. Hopefully this won't start the silicon fluid debate again- last weekend I drove the TF I helped restore 15 years ago. Minimal mileage since then (2000), and the silicon fluid filled brakes are absolutley perfect! Other than adjusting they have never been touched. No way that would happen with regular fluid in our hot and humid climate. George
George Butz

This thread was discussed between 05/03/2005 and 08/03/2005

MG TD TF 1500 index

This thread is from the archive. The Live MG TD TF 1500 BBS is active now.