Refilling a dry brake system?
 

I noticed that one of my brake pistons is leaking brakefluid. I have drained the system and removed the brake calliper and pistons andcan see that one of the seals has perished. I’m going to give it all a goodclean and replace the seals. I wanted to know what would be the best way torefill the dry brake system with new brake fluid and try to minimise air in thesystem.



Thanks in advanced

Re: Refilling a dry brake system???
 

Fill it and bleed it, it is not hard.

Fill it up, if you point master downwards by turning bars gravity will help, leave nipples open for a bit and it should pretty much fill itself.

Re: Refilling a dry brake system???
 

It can sometimes be a bit difficult to get a master cylinder to prime itself and get the fluid initially going down the brake lines. I usually cheat and fill up the system with a syringe full of brake fluid put in through the bleed nipple, but another way is to either take the calipers off and hold them above the master cylinder, or the master cylinder off and put it below the calipers. This is because air rises and the big "bubble" of air you will have in a dry system goes up the pipe as quickly as you are trying to push it down and out the bottom, especially true if you have a twin line system like many race/track bikes. You can also sometimes get a bubble "trapped" if you have one of the up and over systems where the left caliper is fed by a tube that goes up and over the mudguard from the right hand one.

Re: Refilling a dry brake system???
 

I connect a stirrup pump to the bleed nipple and suck the fluid through the system from the master cylinder. Keep an eye on the level in the master cylinder. Once you have it coming out the bleed nipple then just bleed the air out as usual. This is a very quick method.

Re: Refilling a dry brake system???
 

I'm with YC, but I did buy a MytiVac bleeder years ago and have found that this is fabtastic for initially pulling the fluid through to the calipers but once the fluid has come through I bleed it manually with a spanner, length of hose and a glass jar.

To be honest, the last few times I've done it I don't think I've even touched the MytiVac, it's just for difficult ones now really

Re: Refilling a dry brake system???
 

would the vacuum from the carbs/TB's suck the fluid threw?

hose from bleed nipple into a jar with hose going threw lid down to bottom of jar then another hose from top of lid going to vacuum point.

start bike then crack the bleed nipple till fluid runs then close bleed nipple then bleed as normal using leaver.

Re: Refilling a dry brake system???
 

Risk of brake fluid into engine if you're careless, I probably wouldn't bother. A syringe is a quid if you want to use vacuum...

Re: Refilling a dry brake system???
 

was just curios. i have a vacuum pump for doing it :-)