TR6 71 TR6 Master Cylinder and Booster Questions

[Renoman]

I separated the master cylinder from the booster so I could repaint it and the lower part of the firewall. Upon separation I could see a little wetness between the two. What was really odd, to me, was that there was some brake fluid in the booster. I removed the vacuumn connection and drained out about a 1/4 cup of brake fluid. Obviously I'll have to rebuild the master cylinder. I don't know if it's an original master cylinder or after market. I was curious if the rebuild kits sold by most vendors will work since I think the original master cylinders and the aftermarkets may not share the same kit. Any help is appreciated in identifying which one I have. I'm also curious if the booster is ok if I just drain it, possibly flush it and dry it and attempt to put it back in service. Being brake fluid I don't think it would adversly affect the booster but I'm not an expert. Any help here is also appreciated.

Art

 

[tdskip]

How does the M/C look inside Art? Any pitting?

 

[Renoman]

I haven't dismantled it yet. I'm sure if there is significant pitting it may require replacment but I'll take it apart and inspect it asap. Maybe a light hone and rebuild may restore it. Will know soon enough. It's getting late here in Reno, NV.

Art

 

[BobbyD]

When my M/C failed, it too dumped brake fluid into the servo, which then leaked down the inside of the car and did it's paint remover thing on the pedal box. What I've seen over the years is that M/C & servo fixin' falls into 3 camps: people who rebuild themselves with success, people who rebuild themselves only to see it fail and people who go for professionally rebuilt or new. Rebuilding requires getting a perfectly honed surface to ensure it doesn't fail and even then it's no guarantee. Many of the professional rebuilding places chose to install a liner rather than rely on simply honing so that should tell us something. Someone told me long ago that when you're working with hydraulics, you're better off leaving the repair to the pros.......especially on a system that STOPS your car. That's just my 2 cents and YMMV.

BTW.......Ted Schumacher at TSI sells rebuilt servos at an excellent price. They're not listed on his site so you have to call and ask.

 

[DNK]

...BTW.......Ted Schumacher at TSI sells rebuilt servos at an excellent price. They're not listed on his site so you have to call and ask.

That guy needs a website developer and maintainer.

 

[tdskip]

YSDMV - your stopping distance may vary....

 

[kodanja]

the same thing happened with mine when I was rebuilding my entire brake system.
The diaphrams in the boosters have a tendency to stretch out'
Your best bet is to send the booster out to be rebuilt'

 

[BobbyD]

...BTW.......Ted Schumacher at TSI sells rebuilt servos at an excellent price. They're not listed on his site so you have to call and ask.

That guy needs a website developer and maintainer.

I agree but not everyone is as web savvy as we are

 

[Renoman]

I just dismantled the master cylinder and I do see some pitting at the very end of the bore toward the booster side. The previous owner said he rebuilt it but if he did he didn't do much. The lip on the seal doesn't look sharp but I'm not sure if it's supposed to. I may just hone it out to see how far out it has to go to be smooth. There are some numbers on the side of it, 64676888. There is also a red zip tie kind of thing on it. Any help appreciated.

 

[Andrew Mace]

Those red zip tie things are usually found (only?) on original master cylinders. (Other similar Triumph cylinders had different colors.) Does it have a number on it as well? I don't see 64676888 in my Girling catalog for 1971 Triumph, so I wonder if it might only be a casting number or a part number for the cylinder body (which usually wasn't available separately).

 

[Renoman]

The tag has numbers and the casting does have what appears to be a 3 digit number 375 and G on it below the rear reservoir. The tag numbers are 8822 EC23 and 60 30 or 40 812. The pitting is about 1/2" up the bore and after looking at the primary piston and seal it looks like the pitting is right at the seal location. Probably the reason it's leaking. I've read that aftermarket and original castings don't use the same re-build kit. So I'm not sure what to do. I might just hone it to see what the clean bore measures and go from there. Thanks