99 300exc front brake wont bleed

We had to replace a front brake line on my father in laws 99 300 exc its an OEM part. Good air flow through the line when we tested to make sure there is no blockage. We also pumped the brake with my finger by the nipple and air is most definitely being pushed out so I am not sure why we cant get fluid down all the way through. Any thoughts or suggestions would be awesome. Using DOT 4 fluid

have you tried reverse bleeding?

inject your fluid from the bleeder on the caliper with a seringe while the cap on the handlebars is open.

When I can't get a brake to bleed. I use a syringe and

Push the oil threw the Bleeder on the caliper up to the

Master cylinder.

have you tried reverse bleeding?

inject your fluid from the bleeder on the caliper with a seringe while the cap on the handlebars is open.

That was the next thing we were going to try but I am not that familiar with the brembo brakes and didnt know if it was an issue these have or something.

I am going to try that tonight and see if it works.

Was the brake spongy before the line replacement? Brembo's are notorious for getting soft and you can't get them to firm up....

Was the brake spongy before the line replacement? Brembo's are notorious for getting soft and you can't get them to firm up....

It was firm before we replaced the line.

I am no beginning to think that its a bad master cylinder. I took it apart to see what was going on. There was lots of rust in the bottom and a film coating the metal. Also it seems like it will only push air but never any fluid. Even doing a reverse bleed with a syringe it just ends up pushing air into the line.

Here is a link that may be informative: http://www.youtube.com/dirtwiseridingschool

A trick you can try is to tape, vencro, whatever the brake lever down overnight. This may help if there is air trapped in the line.

I just happen to have a front brake assembly for that bike sitting on a shelf;)

Joe...........

Here is a link that may be informative: http://www.youtube.com/dirtwiseridingschool

A trick you can try is to tape, vencro, whatever the brake lever down overnight. This may help if there is air trapped in the line.

I just happen to have a front brake assembly for that bike sitting on a shelf;)

Joe...........

thanks for the video and the tip Ill try that.

Sounds like you might consider a piston and cup set and rebuild it. The other trick is to back the adjustment screw out when bleeding to get the piston past the check valve to get the air out of the mastercylinder. When done then screw it back in and add a couple of clicks with plyers to get a better feel as well.

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