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Master cylinders questions

Bayless

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My Sprite is an early '67 and has the master cylinders that look like 2 little cans. Is it recommended to kit these cylinders or should I replace them? Also, what are the recommendations, pro or con, on using silicone fluid? I have had silicone in the Beetle for years and been happy with it but I have always stayed with LMA in the Prefect.
 
LMA period. Do not go to silicone. And replace. Bores will be pitted and getting out to one seal is almost impossible much less replacing without buggering it up. This is your life we're talking About after all.
 
Well for one, each and every component including wheel cylinders, Calipers, and brake lines are contaminated with LMA which does not mix with Silicone based fluid. Do a Search on Silicone vs. LMA and you will find article after article whith people on both sides of the fence on that topic. I've had good luck with Castrol LMA over the years. That's what or cars were designed to use. And that's what I use still today.
 
The web is chock full of pros/cons. a fellow that is piece mealing a restoration it's understandable to go with what is already present. A complete/ entirety hyraulic replacement could go either way. I asked our opinion, respect it and I thank you, sir!
 
I use silicone and am very happy - however, that was in the context of replacing the entire system. If you are replacing or kitting the MC - keep mineral based.
 
My Sprite is an early '67 and has the master cylinders that look like 2 little cans. Is it recommended to kit these cylinders or should I replace them? Also, what are the recommendations, pro or con, on using silicone fluid? I have had silicone in the Beetle for years and been happy with it but I have always stayed with LMA in the Prefect.
I’m one of those strange people who use Dot 3/4 in one LBC and silicone in another. I like the paint safe aspect of silicone and since my cars are not daily drivers I prefer it over Dot3/4. Silicone does not like to be agitated and special care needs to be taken when filling the MC reservoir to keep the air bubbles to a minimum so the pedal does not feel spongy. Both work and it depends on what you want.
Rut
 
It turns out both my master cylinders are pitted so that settles that question. Paint safe is what attracts me to silicone too. When I converted the VW, I replaced all the cylinders and hoses then flushed the hard lines with mineral spirits then lacquer thinner and finally lots of air. That was over 20 years ago and never a problem since. It looks like the Sprite will have all new cylinders and hoses now too so still considering.
 
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