Leaking tiliton series 75 master cylinders

[Learjockey1]

Need help: only have 3,500 no race miles on a new 3/4 inch brake tilton master cylinder in a 539 framed ERA. Master cyl is leaking at the front boot, not the reservior adapter. Masters were installed with much care and attention to detail as I did not want to do this again. When I purchased the car the tilton masters were leaking and DOT3/4 and lifted the powdercoat. I sanded feather edged primed and repanted only to have it happen again. Are there better masters or is this a quirk. DOT 5 looks better all the time. Too much paint damage with a small problem.

Tilton seems to have strong pull on the market and lots of users, but so far I am not impressed. The ERA/ BMW 2002 steel slave /master clutch set up is perfect.

Anybody have problems with new aluminum 75 series Tiltons (Purcased last year) leaking out of the front seal.

Thanks

[vettestr]

Hey Lefty,
Not that it will stop you from having to repair again but I have not seen multiple failures or heard of any issues. Do you have any severe alignment issues? Is the cup/piston being pushed sideways? How about the length of travel causing a problem, can your pedal bottom out in the bore? I bet you already checked the things mentioned so I am out of reasons for a failure.

[Barnsnake]

The Tilton 75 series have unplated aluminum bores. They do wear, especially if the thrust is not exactly straight down the bore. If there is a considerable angle they will wear quickly and eventually get sufficiently out of round that they leak past the piston.

CNC Brakes makes bolt-in replacements in either stainless-lined-aluminum or steel. They've worked well in my experience.

[vector1]

i have never heard/seen anything that would point to continuing problems with their stuff.

i do know that our aluminum brake calipers on the racing karts (mine and a friends) were severly corroded from what i would think is water being introduced into the fluid from heat and reacting with the aluminum, probably over a span of 3-5 mos. when not in use.

[Learjockey1]

Sorry guys it is a series 74- ¾”.
Just talked to Bob at ERA ad he said they do not have “much of a problem” as in “no”. I asked if my frame number had issues and he said “no” again, so it must be a quirk. Bob said they have good luck so try another. Vettestr , your “thought line” was right on. That is why I mentioned the ERA 539 frame number. I am not bottoming out. I have assembled the tandem tube and all ERA parts and shims to spec with a “cross check” eye on alignment and straightness when under the car. I did engineer a rubber “stop” pad on the brake pedal lever to reduce pedal slop, but do not think it is preventing the pistons from returning/bottoming against the internal cylinder snap ring. I will take a second look, but the brakes are returning and the both front and rear brakes are not heating up. Thanks to all for the inputs. Vector 1, car has not set long enough for corrosion and I am using ATE Blue which is supposed to be one of the best fluids out there. About 6 months old now.
Barnsnake, I called CNC about their steel units but they do not have a top vertical port, only a rear horizontal port. I would have to weld a bung on the top behind the remote reservoir feed for my pressure line take off as the ERA uses the horizontal rear port for the brake switch. I can do this, but I figured I should not have to with the availability of current units.
Tilton said if I sent it to them they would look at it. Nice offer but does not cover damage and repair time.

Again, thanks to all

[twobjshelbys]

My car had CNCs installed. During my clutch problems I replaced the master. It turned out to be the Mcleod hydraulic throw out bearing. The CNC master never had any issues.

[strictlypersonl]

LearJ,

One thing that you should do when you replace the master next time: Flush the reservoir and feed line. Maybe you've got some dirt in the system.

[RallySnake]

LJ,

I have always bought Willwood master cylinders and have used them for years without a problem. I have used one Tilton unit to get an odd size (maybe 11/32) and it worked fine too. They are heavier than Willwood, cost more and are harder to find, though. I do replace all my fluid every two years and use only Castrol LMA fluid.

If I were having the kind of luck that you have, I would make a plastic shield for the area below the master cylinder. Just cut up a molded plastic box (or tupperware) and position it so it directs the fluid away from the painted surfaces. Done creatively, it can look pretty good.

RS

[Learjockey1]

RallySnake, Good Idea, I was thinking about running a drain tube from the pushrod boot straight down to the outside bottom of the car. Because if it leaks now the paint is gone. This is a small leak. I cannot tell from the reservoir level , but when I removed the control box cover I saw the damage. White Post Restorations can put a brass sleeve liner in the cylinder housing. When I get the time to get the old one off and see what Tilton says. I sorta like the steel ones at CNC's. I just cannot see the aluminum cylinders lasting as long as steel. May be fine for a year or two or a race car getting carefull attention after every race. My Winston Cup friend at Roush/ Yates that they rebuild them after 3-5 races but they are not leaking when they rebuild them.

Bob, I was pretty thorough on the flush from the reservior through the new lines to the 3/4" MC but, sometimes, "if it can happen it will happen", Thanks