Re: vegetable oil = brake fluid?

[Simon Favre <simon@domain.elided>]

The last car I saw that specified vegetable oil as brake fluid was Peter
Giddings' pre-war Tipo C race car. It had been converted to conventional
brake fluid, but it still had a lovely brass plaque specifying the use of
vegetable oil. I was pitted next to him at a vintage race last year, so I
had to ask.

I would be surprised if Lancia was still specifying this in 1967. I suggest
that any mechanic who does this nowadays isn't doing you any favors. What
happens if you have to have the car serviced someplace else? If this car
has been run on vegetable oil for a long time, I would either keep it that
way until a brake problem developed, then tear the whole system down for new
seals, or just bite the bullet and tear it down right away. Castrol LMA is
very good stuff. Silicone brake fluids have their own host of problems. If
you do switch over, a good DOT4 should be fine. The Castrol seems to be
gentle on the older systems. Since it's the same amount of work to pull all
the hydraulics apart whether you replace the seals or just clean them off,
I would replace them. You also need to replace the flex lines. Any rubber
parts that have soaked in vegetable oil should be replaced.

Megan Caverly wrote:

>In addition to our Alfa's I have a 67 Lancia Fulvia Zagato that I
>bought a little over a year ago.  Most bugs have been sorted out, but
>I'm left with a very strange one that I'm hoping the accumulated
>wisdom here can help with.  The PO had the car serviced by a very
>old-worldly minded mechanic who used vegetable oil in place of
>standard brake fluid.  Per the manual, and I guess once upon a time
>practice, this is/was a legitimate substitution option!  I do not want
>to perpetuate it however, so does anyone here have any pertinent
>experience with changing a brake system over from vegetable oil to
>proper brake fluid?  I need to replace my brake lines anyway, so
>they'll be fresh, but I'm wondering about seals, MC, etc. TIA,
>
>Megan Caverly
>
>P.S.  This is not a jest - I truly have veg.oil in the system, it's
>weird stuff, and I want it replaced without worrying about a system
>failure.  Body bits for this car are pretty much unobtainium.

------------------------------