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Brake Fluid- Silicone?

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HAN8L1965

HAN8L1965

Jedi Warrior
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I know this has come up before but I had a recent event and am just wondering. Two weeks ago my drivers side caliper decided to leak and within a couple of days it drained the system. All parts are new rubber, all new stainless lines and newly bored and rebuilt master cylinder. I used fresh silicone brake fluid. Some of the rubber pieces seemed hard. For the most part this car has never been driven just waiting for the day. The system has been filled and in place for about a year. What gives has anyone else had a similar experience? Should I go back to the old syle fluid????? So many questions but I want to hit the road with confidence.

Mark
 
Its been a long time since my schooling for mechanics but isnt silicone brake fluid for certain brake systems?
 
I've had similar problems with my '59 Bugeye. New restoration yet the right rear cylinder is leaking. New rubber and all........doesn't seem to affect the paint but does it dissolve the seals?
 
I have had silicone in my Austin A40 for 13 years with no problems.
I run it in all my Sprites (4 on the road) and have never had a problem, the oldest has had it for 7 years now. The latest just a couple months.
It does eat pressure brake light switches so all silicone fluid cars are running mechanical brake light switches but that's the only problem I ever had.
Even the pressure switch for silicone fluid only lasted a month or so.
I swear by the stuff.
Did you guys use genuine Lockheed kits or cylinders in your rebuilds?
I did, there is some real junk aftermarket brake kits out there.
 
I'm using silicone with no issues at all. There were issues with old rubber, but, any new rubber will be no problem. As my friend Larry put it, if silicone ate new rubber the lawsuit line would stretch around the block. I'm inclined to think defective parts. Certainly the country of origin of many of these parts matters. Was at my auto parts guy yesterday and we got talking rebuilt shocks. He was saying that the first attempts to reproduce lever shocks in China resulted in a 30% failure rate - hence his suggestion to get a rebuild. On the other hand he talked about repro master cylinders that were good and cheap enough to not need to rebuild - so, it seems like its a crap shoot with some of these parts. Certainly we've had many conversations here about chinese vs. UK produced body panels and it still irks me that my replacement solenoid has metric nuts.
 
I have had silicone fluid in my MGB for close to 30 years and the brakes work great. Also within the last ten in MGA, Bugeye, Midget. I'd go with spritenut and blame substandard parts. Will say that I can't seem to make pressure brake light switches, that are new, work with it and have fitted mechanical switches as well. I have been blameing the switches, maybe there not the problem. I'd like to see another british car that has'nt needed brake system work in 30 years. I'm sold on silicone.
KA
 
Ten years with silicone on my Big Healey no problem, now am doing a Triumph, the kit I got for the front disc was simply crap, got a Beck Arnley kit, much higher quality, unortuneately with the "big box" british parts houses you don't know where the parts you order are going to come from until you get them.
 
I've had DOT-5 fluid in our GT6 for 16+ years and in the Mini for 8+ years without any issue... other than the brake light switch mentioned above. I'm another person who converted my pedal box for the mechanical switch. It's a sacrifice away from originality that I'm willing to make.

Eventually someone will chime in on this thread about all the evils of DOT-5 fluid (trapped air bubbles, pooling water in the lines, sponginess....) However, for a street car which isn't getting regular brake flushings and with nice new paint, I also swear by DOT-5.

Consider this another vote for your current problem being the result of defective or sub-standard parts. Out of curiosity, when you rebuilt the calipers did you do a very thorough cleaning of the seal grooves in them? Did you get any/all of the rust out of the grooves and what condition were they in before fitting the new seals?
 
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