Author Topic: Bleeding brakes and clutch slave cylinder (Read 3531 times)

manydubs · « **on:** May 08, 2009, 01:06:54 PM »

I bleed my brakes the other day, along with the clutch. The front driver side would not bleed. I checked out the bleed screw, caliper and rubber line and was able to remove and blow compressed air trough them fine.

Do I need to activate the ABS to get fluid to all calipers?

Also, after bleeding the clutch the pedal has no feel to it, it is very soft and there is no reistance.

Will it get pressure when the car i started and the brake booster produces pressure from the engine pressure?

Thanks.

DesktopDave · « **Reply #1 on:** May 08, 2009, 10:23:13 PM »

You need to get the air out of the lines. The brake booster uses engine vacuum to help you press the brake pedal down. Check for leaks, check for a seized caliper. How are you bleeding the lines, with a helper, vacuum pump or pressure bleeder?

twright · « **Reply #2 on:** May 09, 2009, 06:59:16 AM »

I have found some caliper bleed screw ports to get plugged with crap. If nothing comes out when you open the screw, stick a pick (or open paperclip ) in there and see if that opens it up.

manydubs · « **Reply #3 on:** May 12, 2009, 03:01:10 PM »

Blew air through screw, rubber line and caliper recesses..

manydubs · « **Reply #4 on:** May 12, 2009, 03:01:42 PM »

Helper is pushing down pedal...

DesktopDave · « **Reply #5 on:** May 13, 2009, 08:21:19 AM »

Do you have much of a history on the car? Have either of the master cylinders been replaced? If the brake pedal is firm when your helper is pushing it, I'd be sure you have a plugged line. I can't think of any other way that fluid wouldn't get to the brake, unless it's leaking out of the system somewhere. Sometimes a master cylinder will leak internally too, into the brake booster cavity. If you have a lot of miles on the car you might think about replacing that master cylinder just for peace of mind.

Does the clutch work? I've noticed a few times that a good clutch bleeding really changed the feel of the pedal. Most times it hasn't though. If it's not working, start thinking about a new slave cylinder.

You could also unscrew the bad caliper's hard line from the ABS pump, get a catch can under there, and see if any fluid is coming through when the pedal is pushed down. Blow downstream through the line toward the caliper to see if the line is clear. I hope you don't have a plugged circuit in the ABS pump itself.

I've heard of a few times that the ABS pumps were clogged by forcing fluid backwards from the calipers during pad changes. I've never seen that myself...and overhauling ABS pumps is not something I've ever been tempted to do.

manydubs · « **Reply #6 on:** May 15, 2009, 06:56:06 AM »

Looks like a plugged circuit in the ABS for the driver side, removed metal line at ABS and it is dry. Attempted to pump fluid out and would not.

Removed passenger side connection at ABS and it pushed out fluid fine.

Going to remove ABS from the mix with a T fitting for front and metal line to line adapter for the rear.

DesktopDave · « **Reply #7 on:** May 15, 2009, 07:08:52 AM »

If you don't want to remove the ABS unit I have one from an '88 325is you can have. I'm not sure it's totally the same, but it's yours for postage if you want it.