Greetings:

I have had brake dilemma most of this week up until today. My brake pedal was extremely soft and would often skid stop the car (rear brakes). Then my master cylinder went out! I then was faced with total brake failure! After conveying enough information from this board, I then replaced the master brake cylinder and the booster valve with donors from the junkyard. The master cylinder replacement was in very new like condition and very clean (ATE)as was the servo booster valve. I removed the master cylinder valves (4 total) via a 6 point 11mm wrench. The rear nuts at the servo booster/Master Cylinder connection were 17mm. I notice a gush of air to come out of the booster when I exchanged valves. I then installed the replacement MC and all connections. I then re-filled the reservoir with fresh DOT 4 brake fluid. I then cracked open each MC valve, and I had my helper push the brake pedal (not too hard/half way). I then observed several air bubbles to come out through these 4 valves. My helper release the pedal only after I closed all 4 valves (11mm wrench). I did this for a total of 3 times. Again several air bubbles were extracted out. I then turned to bleeding all 4 calipers. On the dual bleeders on the front girling calipers I bleed the top first and then the bottom second on each wheel twice. I then moved to the rear calipers and bleed each (single bleeder) rear wheel twice. I replaced the rubber bleeder caps and test drove, to my delight the brakes were extremely firm! My pedal travels at the most 1- 1 1/2 inches to a firm stop! Thanks to all and most of all thanks to this brickboard forum!!! I agree with several members get the genuine parts, especially when it comes to brake components, I was lucky to get such a clean recently installed donor master cylinder from another 1991 740 wagon. The dealer wanted nearly $300.00 for a MC and 140.00 for a rebuilding kit which just consisted of just a few parts and seals, FCP had a bargain price of under $200.00. Again many thanks!!


1988 740 GLE S.W. 8 VALVE Non-turbo/non ABS A.W. 70 A.T. currently 430,500 Original miles
1989 740 GLE S.W. 8 Valve non-turbo/non ABS A.W. 70 A.T. currently 393,300 original miles excellent condition, strict maintenance/premium fuels/lubricants/fluids/coolant/parts. (NGK-V-power sparkplugs) no oil leaks/burning 27-30 mpg 99% hwy miles smooth/strong acceleration. Neither of these vehicles would have no problem in doing what the dashboard have on it!