Lotus Elan

Changing brake fluid

PostPost by: jimj » Tue Aug 05, 2014 3:11 pm

A recent article re. the above prompts me to get around to changing my brake fluid. Still Dot 4, of course, and fresh. I read somewhere that when bleeding the brakes you shouldn`t push the brake pedal all the way down, in fact scarcely further than the pedal travel when you normally brake. Is this so? Why?
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PostPost by: mbell » Tue Aug 05, 2014 7:04 pm

I think the theory is around the wear/dirt in the bore of the master cylinder that could build up during normal use. Pushing the peddle past the normal range of peddle movement could push the seal into an area dirt or build up that could damaging the seal.

Whether this is a real issue I am not sure, probably depends how well the system has been looked after. If it's well looked after then there probably nothing in there that would damage the seal...

Using a pressure/vacuum bleeder is likely to avoid any possible risk here.
'73 +2 130/5 RHD, now on the road and very slowly rolling though a "restoration"
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PostPost by: oldchieft » Tue Aug 05, 2014 8:48 pm

It is rust and corrosion that will cause the piston to stick.

It happened to me once when I worked in a garage, a wiser head than mine hit the master cylinder with a hammer and it sprang back.

It is worth knowing about but easily forgotten.

The hit it with a hammer fix works more then half the time.

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