[Spridgets] brake fluid question

[Jim Johnson]

Ryan,

I would definitely drain the system and refill with fresh brake fluid. I
believe you can use either DOT3 or DOT4.  I use DOT3 in both clutch and
brakes. Hydraulic fluids should be changed regularly anyway. They are
hygroscopic meaning they absorb moisture from the air which contaminates
them an eventually will damage parts of the system from the inside. DOT3 and
DOT4 should be readily available just about anywhere. WalMart has it.

Are you sure its your master that is leaking and not one of the wheel
cylinders?

Cheers!!
Jim

On Sun, Apr 12, 2009 at 4:07 PM, <ryan.kubanoff at comcast.net> wrote:

> I have a 74 with a bad master cylinder thats going to be replaced tomorrow.
> But now the question is brake fluid and what to use. I presume that the
> system has original or older DOT4 although last month when i noticed the
> leak in the resevoir i topped it off with 20ml of DOT3 (i didn't know any
> better). Today when I went to pepboys for a quart of DOT4 all they have is
> the castrol synthetic slm that "meets or exceeds DOT3 and DOT4 standards".
> now i have not seen any more leaking in the past 2 months so i am thinking
> that my DOT3 addition is still in the master resvoir but?
>
> Advice needed. do i drain the whole system and refill with the new castol
> stuff, do i drain just the master and refill with the new castrol, or some
> other suggestion.
> Thanks
> ryan