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Master cylinder pushrods
Slimy38 - 28/3/16 at 09:14 AM

I'm looking at the hydraulics from my donor MX5, and the master cylinder pushrods are a little concerning. At the moment, they are attached to the pedals, having been pulled out of the master cylinders (brake and clutch). But I thought the pushrods should be retained? What's to stop them just falling out and dropping down if for some reason the pedal is allowed to come back too far?

Is it potentially an IVA fail to not have retained pushrods (circlip or similar)? Am I overthinking something that is perfectly normal?

adithorp - 28/3/16 at 09:39 AM

Over thinking. Lots of cars have pushrods not retained at the cylinder. Once it's all together the pedals shouldn't return far enough to let them escape.

PS. Remember to adjust the pushrod length so you have slight free play when the pedal is at rest.

[Edited on 28/3/16 by adithorp]

Slimy38 - 28/3/16 at 09:49 AM

Awesome, thanks.

MikeRJ - 28/3/16 at 12:11 PM

quote:
Originally posted by Slimy38
But I thought the pushrods should be retained? What's to stop them just falling out and dropping down if for some reason the pedal is allowed to come back too far?


The pedal should not be allowed to come back too far, you should have a stop installed to prevent this. Try pulling up on the brake pedal in a production car, it won't move.

Slimy38 - 28/3/16 at 12:26 PM

At the moment my pedals are just bits of metal, but yes I was going to build in stops for fore and aft movement.