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MG TD TF 1500 - Rebuilding of a master cylinder.

Where can I find some good write-ups on the removal, replacement and rebuilding of the master cylinder for an early TD?
Mort 50 TD

Rebuilding is pretty straight forward just be very cognizant on where the various bits go in order of assembly. I will suggest though that you thoroughly prime the pump on the workbench to insure it is squirting properly and the the piston returns and refills. Lubricate the seal and cylinder with brake fluid prior to assembly as well. I have put masts cylinders together twice now without priming on the bench and ended up taking them back out to insure proper function because I could never get the pump to work properly when the lines were offered up to the pump discharge. Saves time and frustration.

Bill Chasser
W. A. Chasser

Mort, check the archives for 'Tight m/c rebuild' . It's an experience that I (with the help of George Butz III) had a few years ago. I'm not sure about my trust in the quality of rebuilding kits. When I did my switch to silicon I opted for a new m/c. Then again, how good are the new ones. Good luck. Bud
Bud Krueger

Water has a bad habit of settling down the the bottom of the master cylinder and pitting it. When you get it apart, shine a flashlight into the bore looking for the pits. As they form a line along the bottom, you can appreciate that honing isn't going to smooth it out and a new seal won't necessarily make it leakproof. It may require sleeving.

As I commented via email, if you want to imrove your braking power, consider sleeving it down to a smaller bore. I skimmed the Workshop Manual and couldn't find the original ID, but I recall from years ago, stock is 7/8" and my choice of replacement was a dual circuit MC with 3/4" bore.

Mort - there are also original, replacement, new replacement, and unavailable replacement master cylinder kits. Be sure which you have (I seem to remember that Moss has a write-up).

I get my original master cylinders re-sleeved in brass by Mark Frappier in Agawam, MA.

Tom Lange
MGT Repair
t lange

this is not necessarily a recommendation but about two years ago I did mine with a Moss rebuild kit and had no difficulties. I have seen several articles on too tight assembly and out of tolerance seals.

My master cylinder had no pits so after a cleanup and a priming in the vise it went in with no difficulty. Good luck and hope for no pits. I changed the complete system and went with silicone fluid. Yesterday everything was fine about two years later.

Jim Hasjins 1953 TD
J M Haskins

There are some nice looking rebuild kits on ebay that include new pistons. From Argentina of all places.
George Butz

Last night on a repeat of "Chasing Classic Cars" Roger rebuilt a Master Cylinder (Well he took it apart at least) on an early Buick Roadmaster.

Jim B.
JA Benjamin

This thread was discussed between 08/10/2016 and 09/10/2016

MG TD TF 1500 index

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