BMW Turbo Discussion  - BMW 745i and BMW Turbo Project Forums
User Name:
Password:
Save Password
Forgot your Password?
Home | Active Topics (0) | Members | Online Users | Statistics | File Library | Search | Avatar Legend
 All Forums
 Normally Aspirated BMWs
 The E23 Board
 Braqke problems
Next Page
 New Topic |  Reply to Topic |  Bookmark Topic |  Printer Friendly
Author Previous Topic Topic Next Topic
Page: of 5

Jon 86 745 MS
Over 745 Posts!

Status: offline


1423 Posts

Posted - Jan 20 2003 :  20:23:01  Show Profile  Reply with Quote
Ok, my brakes have been soft for a while. I have to push the pedal down about 1 1/2 inches before it begains to stop. I have replaced all of the calipers, rotors and replaced the steering pump and the regulator. All of the brake hoses are also new.

I thought it might be the master cylinder but pumping the brakes does not help the issue any. I am running out of ideas on what to do. Any suggestions?

I also tried to take apart an older Master cylinder I have but cannot get the clip out of the back. It is not your standard snap ring. It has no place to get any tools on it. Once I get it apart is there any kits or am I better off getting a replacment from the local autoparts for $82.00.

Jon Jacobs
85 Korman 745i (AKA Das Borg) R.I.P.
86 745i (Die Rakete)(no mas :(
1.2 bar + Boost with
Team WWW.745i.com Performance Parts

stevecots
Master Technician

Status: offline


215 Posts

Posted - Jan 20 2003 :  20:33:25  Show Profile  Reply with Quote
Jon,
To the best of my knowledge there is no master cylinder kit available unless you are an official rebuilder. It's odd, but I'm told for liability reasons. Same for the Brake Booster. We've gotten around the brake booster except fro the seal that seals the shaft. Joe Gisler is the only on who has been able to source that seal. I'ld buy a new one for the longevity anyway. steve
Go To Top Of Page

Jon 86 745 MS
Over 745 Posts!

Status: offline


1423 Posts

Posted - Jan 20 2003 :  20:57:16  Show Profile  Reply with Quote
Thanks Steve, I have sourced the seal and other parts in the brake booster. Took a while and even had to have some of them made. I guess though on the master cylinder I will have to find a new or rebuilt one.

Jon Jacobs
85 Korman 745i (AKA Das Borg) R.I.P.
86 745i (Die Rakete)(no mas :(
1.2 bar + Boost with
Team WWW.745i.com Performance Parts
Go To Top Of Page

Afshin-Switzerland
Over 745 Posts!

Status: offline


1847 Posts

Posted - Jan 20 2003 :  21:40:30  Show Profile  Reply with Quote
Jon,

Sorry stupid question but I just have to ask , did you ever check that break bomb ? That's where I would start to look at anyway ... Had the exact same sympthoms on my both E23's and break bomb was it.

Regards, Afshin.
1982 745i (5-Speed)

Regards, Afshin.
1982 745i (5-Speed)



Edited by - Afshin-Switzerland on Jan 20 2003 23:15:17
Go To Top Of Page

scottie
System Administrator

Status: offline


3845 Posts

Posted - Jan 20 2003 :  23:16:58   View scottie's Photo Gallery  Show Profile  Visit scottie's Homepage  Send scottie an AOL message  Reply with Quote
I have the same problem...although I also replaced the master cyl. My best guess is air in the abs lines. Do a search. I talked about this problem previously but I have still not resolved it. It has been with my 745 since I got it. I think I asked this before, but don't recall then answer...do you need to bleed the abs system in a special way?

Scottie Sharpe
San Jose CA
Discussion Board SYSOP


88 Dinan M5
1968 2002


FOLLOW ME ON FACEBOOK
My Profile
Go To Top Of Page

Jon 86 745 MS
Over 745 Posts!

Status: offline


1423 Posts

Posted - Jan 21 2003 :  04:42:59  Show Profile  Reply with Quote
Replaced the brake bomb a while back. I have pressure bleed and bleed by pumping the brake. I would think by now that I would have gotten all of the air out. I am definitly no brake expert. I would just like to have firm brakes.

Jon Jacobs
85 Korman 745i (AKA Das Borg) R.I.P.
86 745i (Die Rakete)(no mas :(
1.2 bar + Boost with
Team WWW.745i.com Performance Parts
Go To Top Of Page

Jon 86 745 MS
Over 745 Posts!

Status: offline


1423 Posts

Posted - Jan 21 2003 :  07:32:03  Show Profile  Reply with Quote
Can anybody while the car is running push hard enough to mash their brake pedal all the way to the floor? I am just trying t figure out where this soft pedal is coming from.

Jon Jacobs
85 Korman 745i (AKA Das Borg) R.I.P.
86 745i (Die Rakete)(no mas :(
1.2 bar + Boost with
Team WWW.745i.com Performance Parts
Go To Top Of Page

dnliii
Over 745 Posts!

Status: offline

1405 Posts

Posted - Jan 21 2003 :  08:39:45  Show Profile  Reply with Quote
Hey Jon Jacobs... After having bled the lines, replaced the calipers, installed new braided lines, I had the same problem. The cure was to not let air past the threads on the bleeder nipples. Two suggestions- a dab of grease around each nipple or remove and wrap the nipple with teflon. It seems that if it was loose enough to bleed, it was so loose that it allowed air back in. The problem is compounded by collapsed brake lines. If you are having a hard time bleeding a line, you end up loosening the nipple more and more to get the fluid out. Big mistake. Have you replaced your rubber brake lines??
Go To Top Of Page

Jon 86 745 MS
Over 745 Posts!

Status: offline


1423 Posts

Posted - Jan 21 2003 :  09:41:50  Show Profile  Reply with Quote
Yes, put stainless braided pnes from Bav Auto. I orderd a master cylinder today. I will try the tape or something first. You would think with the pressure bleeder that no air could get back in.

One thing though I had this problem before I started with the calipers, etc. Thats why the master cylinder is next.

Jon Jacobs
85 Korman 745i (AKA Das Borg) R.I.P.
86 745i (Die Rakete)(no mas :(
1.2 bar + Boost with
Team WWW.745i.com Performance Parts
Go To Top Of Page

turboguy
Grease Monkey

Status: offline


72 Posts

Posted - Jan 21 2003 :  18:32:48  Show Profile  Reply with Quote
Heya Jon...

I know that you replaced the Notro "bomb", but they can be damaged if there is a system "problem"... I had the same problem on my 86, having just replaced the bomb a few months before. Went through and replaced everything and wholla - stiff brakes again after the bomb was replaced...

Oh... Just remembered!!! The brake divider!!! It is what the bomb attaches to... The other 86 I own had that as its problem...

Just some thoughts...

Edward
Go To Top Of Page

Jon 86 745 MS
Over 745 Posts!

Status: offline


1423 Posts

Posted - Jan 21 2003 :  19:40:25  Show Profile  Reply with Quote
Thanks Edward, I replaced the master cylinder tonight and no change. What a pain in the ass that was. All I got from the deal is now my brake booster is leaking. Really sucks.

I will try a bomb next. The thing it screws into I call a regulator. I replaced it with a used one not long ago that I got from the Cell Guru and still is the same. So when I replace the booster and the bomb everything will be new. That should fix it huh!!

Jon Jacobs
85 Korman 745i (AKA Das Borg) R.I.P.
86 745i (Die Rakete)(no mas :(
1.2 bar + Boost with
Team WWW.745i.com Performance Parts
Go To Top Of Page
Page: of 5 Previous Topic Topic Next Topic  
 New Topic |  Reply to Topic |  Bookmark Topic |  Printer Friendly
Next Page
Jump To:

Please consider donating to help keep BMW Turbos! online.
Donate now using the link below. Thank you for helping keep the M102/M106 discussion forum alive!

BMW Turbo Discussion - BMW 745i and BMW Turbo Project Forums © Scottie Sharpe Go To Top Of Page
BMW TURBOS! generated this page in 0.64 secs. Snitz Forums 2000