Anyone got any idea why I'm still getting bubbles coming out ? I'm using a vacuum bleeder and not done before but I've gone through a full 300ml of brake fluid, i'm using old fluid that's been sitting in the shed for years to test with but I just cant get them to stop. I've also taken out both pistons to clean as 1 wasn't coming out when pressing the brake. the brake pedal does go firm and definitely better than b4 but still would like to get rid of the bubbles, I also notice when i touch the bleed nipple is also effects the amount and size of the bubbles I'm getting Appreciate any advice, Ty
Vacuum bleeders tend to pull air in around the threads of the bleeder valve while pulling fluid from the system. A bit of grease or vaseline around the bleeder may do the trick. Or just do a couple of the old pump and bleed method after you're through to satisfy yourself that there is no air in the system.
I believe it is common practice whilst bleeding to unbolt the rear caliper and suspend it so that the bleed nipple is upper most. That way the air will naturally rise and not stay in a cavity in the caliper.
Thanks Rob at 1st I just unthreaded the bleed nipple a few turns and applied Vaseline, I still got bubbles. I then removed it completely and applied ali slip to all threaded part and hey presto no more bubbles cheers guys
