Unofficial BMW

Unofficial BMW

Google Search

What's New

Search (Google!!)









Used Cars




In Association with

Home E12 E24 E28 E30 E34 E36 Z3 E39 E46 X5/E53 ALL
Ron Stygar Carl Buckland Dale Beuning Forums Help

Unofficial BMW Nav Map

From digest.v7.n455 Thu Oct 16 18:59:23 1997
From: "John H. Stein" <>
Date: Thu, 16 Oct 1997 18:18:45 -0400
Subject: Bleeding brakes w/pressure systems

For those who care, as noted here (and in the 7 series digest) BMW service manuals make a strong diference between bleeding ABS and non-ABS systems.

BMW permits presurized/blo-through systems on non-ABS systems, and recommends a vacuum/suck through system for ABS types. Why??? I don't know, perhaps some better informed techie (only admiration intended) can more fully expound on the WHY aspect. Any comments Chris???

Additionally, for those of us w/ high mileage vehicles, be Extremely careful w/ the old "pump it" method, as that will force the master cylinder past its normal travel limits and will probably cut the edges on the gunk (a VER?Y scientific term... grin) which grows on the cylinder wall.

Lastly, for all of you unfortunates in the cold climes..... if you have ever wondered why auto manufactures in the cold countries (who give a damn about their products) recommend an annual brake system flush.... it is because as the brake fluid drops below freezing, the water vapor which has been absorbed into the brake fluid (as it is hydroscopic, meaning it absorbes water) freezes, it forms razor sharp crystals which cut the poor master cyl seals causing brake failures.... Have you ever wondered about the correlation between brake/hyd clutch failures and the first hard freeze... what a thing to ponder as winter approaches....(sigh another weekend task)

I have a very good home bilt, vacuum based system, and will be happy to forward the details to anyone who asks. (I have posted the info here before and dont want to waste any more bandwidth)

John H. Stein
fax 770 514 8285
85 745 190,000mi
85 735 125,000mi
83 533 226,000mi

Unofficial Homepages: [Home] [E12] [E24] [E28] [E30] [E34] [E36] [Z3] [E39] [E46] [X5/E53] [ALL] [ Help ]