[MBZ] Brake problem: 126, 1990 300S
Re: [MBZ] brake problem
Most likely a defective brake booster. It should hold vac indefinitely. I busted one on the old dodge Aries -- stalled every time I stepped on the brakes. Peter
Re: [MBZ] brake problem
Peter Frederick wrote: Most likely a defective brake booster. It should hold vac indefinitely. Sometimes the brake booster and master cylinder fail together. What sometimes happens is the M/C rear seal fails and fills the brake booster with brake fluid. The brake fluid eats a hole through the diaphragm and the power assist goes away. Now you've got crummy brakes and you're burning brake fluid in the engine (gas car) or sucking it into the vacuum pump (diesel). Used to be real common on some VWs.
Re: [MBZ] brake problem
I thought luther said his brakes were spongy. If he didnt have power assist they would be hard. David Brodbeck wrote: Peter Frederick wrote: Most likely a defective brake booster. It should hold vac indefinitely. Sometimes the brake booster and master cylinder fail together. What sometimes happens is the M/C rear seal fails and fills the brake booster with brake fluid. The brake fluid eats a hole through the diaphragm and the power assist goes away. Now you've got crummy brakes and you're burning brake fluid in the engine (gas car) or sucking it into the vacuum pump (diesel). Used to be real common on some VWs. ___ For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://striplin.net/mailman/listinfo/mercedes_striplin.net -- Kaleb C. Striplin/Claremore, OK 89 560SEL, 87 300SDL, 85 380SE, 85 300D, 84 250 LWB, 83 300TD, 81 300TD, 81 240D, 81 240D, 76 450SEL, 76 240D, 76 300D, 74 240D, 69 250 Okie Benz Auto parts-email for used parts
Re: [MBZ] brake problem
Kaleb C. Striplin wrote: I thought luther said his brakes were spongy. If he didnt have power assist they would be hard. Yeah, I don't think what I described is Luther's problem. If the brakes are spongy he's either got air in the system or a bum master cylinder. Sometimes they leak internally and the pedal will gradually sink, even though you're not losing any fluid.
Re: [MBZ] brake problem
When my MC went on the blink, the pedal went almost to the floor on the first push. Scary. But I had a combination of failing vac.pump and a bad MC. On 11/21/05, David Brodbeck [EMAIL PROTECTED] wrote: Kaleb C. Striplin wrote: I thought luther said his brakes were spongy. If he didnt have power assist they would be hard. Yeah, I don't think what I described is Luther's problem. If the brakes are spongy he's either got air in the system or a bum master cylinder. Sometimes they leak internally and the pedal will gradually sink, even though you're not losing any fluid. ___ For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://striplin.net/mailman/listinfo/mercedes_striplin.net -- Hans Neureiter, Houston, TX '82 300SD, '95 E300D
[MBZ] brake problem
My '82 300CD's brakes are funky. They are very spongy and you have to push them harder to get the same break action. I capped off all vacuum lines and checked the vacuum and have more than 20hg at idle and it drops 5-8hg each time I push the brakes and quickly builds back up. I drove the car for a short distance, and no funky ness in the vacuum there. I then parked the car and watched the vacuum, and it dropped to almost zero after about 15min. Is this normal? What may be causing the leak? TIA all, Luther Luther KB5QHU Alma, Ark '83 300SD (happily running diesel/WVO mix) '82 300CD slate grey, black interior, 152,xxx mi
Re: [MBZ] brake problem
Luther; I had very similar problem on my 300SD. Turned out to be a broken poppet valve (exhaust, to the engine) in the vacuum pump. On 11/21/05, Luther Gulseth [EMAIL PROTECTED] wrote: My '82 300CD's brakes are funky. They are very spongy and you have to push them harder to get the same break action. I capped off all vacuum lines and checked the vacuum and have more than 20hg at idle and it drops 5-8hg each time I push the brakes and quickly builds back up. I drove the car for a short distance, and no funky ness in the vacuum there. I then parked the car and watched the vacuum, and it dropped to almost zero after about 15min. Is this normal? What may be causing the leak? TIA all, Luther Luther KB5QHU Alma, Ark '83 300SD (happily running diesel/WVO mix) '82 300CD slate grey, black interior, 152,xxx mi ___ For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://striplin.net/mailman/listinfo/mercedes_striplin.net -- Hans Neureiter, Houston, TX '82 300SD, '95 E300D
Re: [MBZ] brake problem
My '82 300CD's brakes are funky. They are very spongy and you have to push them harder to get the same break action. They need bleeding. [vacuum] dropped to almost zero after about 15min. Is this normal? Yes, I think so, depending on where you measured it. At the tap for vacuum accessories I think it does leak down to zip normally. -- Jim
Re: [MBZ] brake problem
Vacuum is not your problem. First try bleeding all the brake lines. If that doesnt work, your master cylinder is bad. Luther Gulseth wrote: My '82 300CD's brakes are funky. They are very spongy and you have to push them harder to get the same break action. I capped off all vacuum lines and checked the vacuum and have more than 20hg at idle and it drops 5-8hg each time I push the brakes and quickly builds back up. I drove the car for a short distance, and no funky ness in the vacuum there. I then parked the car and watched the vacuum, and it dropped to almost zero after about 15min. Is this normal? What may be causing the leak? TIA all, Luther Luther KB5QHU Alma, Ark '83 300SD (happily running diesel/WVO mix) '82 300CD slate grey, black interior, 152,xxx mi ___ For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://striplin.net/mailman/listinfo/mercedes_striplin.net -- Kaleb C. Striplin/Claremore, OK 89 560SEL, 87 300SDL, 85 380SE, 85 300D, 84 250 LWB, 83 300TD, 81 300TD, 81 240D, 81 240D, 76 450SEL, 76 240D, 76 300D, 74 240D, 69 250 Okie Benz Auto parts-email for used parts
Re: [MBZ] brake problem
Kaleb C. Striplin wrote: Vacuum is not your problem. First try bleeding all the brake lines. If that doesn't work, your master cylinder is bad. I agree with Kaleb (and hope we're right ;-). Marshall -- Marshall Booth (who doesn't respond to unsigned questions) der Dieseling Doktor [EMAIL PROTECTED] '87 300TD 182Kmi, '84 190D 2.2 229Kmi, '85 190D 2.0 161Kmi, '87 190D 2.5 turbo 237kmi
Re: [MBZ] brake problem
Here's the rest of the story. All 4 calipers were just rebuilt and 4 new hoses were installed. My indy thought the MC was suspect immediatly out of the box (it's a rebuild from Autozone). He bled nearly 1 whole qt of Valvoline Syn+ through the system. The brakes all work perfectly evenly, though weak. I just need to verify that my vacuum system was ok before I order a new MC. Thanks all. Luther -Original Message- From: Jim Cathey [EMAIL PROTECTED] Sent: Nov 21, 2005 9:01 AM To: Luther Gulseth [EMAIL PROTECTED], Mercedes mailing list [EMAIL PROTECTED] Subject: Re: [MBZ] brake problem My '82 300CD's brakes are funky. They are very spongy and you have to push them harder to get the same break action. They need bleeding. [vacuum] dropped to almost zero after about 15min. Is this normal? Yes, I think so, depending on where you measured it. At the tap for vacuum accessories I think it does leak down to zip normally. -- Jim Luther KB5QHU Alma, Ark '83 300SD (happily running diesel/WVO mix) '82 300CD slate grey, black interior, 152,xxx mi
Re: [MBZ] brake problem
Luther Gulseth wrote: Here's the rest of the story. All 4 calipers were just rebuilt and 4 new hoses were installed. My indy thought the MC was suspect immediatly out of the box (it's a rebuild from Autozone). He bled nearly 1 whole qt of Valvoline Syn+ through the system. The brakes all work perfectly evenly, though weak. I just need to verify that my vacuum system was ok before I order a new MC. Thanks all. Luther You have several Mercedes. Go to the one that doesn't have brake problems. With the engine off, press on the brake pedal and THEN start the car with your foot pressing on the pedal. The pedal should drop (maybe 1/2) and feel spongy (I don't know how to quantify spongy). That shows that there is vacuum. The other car should feel about the same IF there is about equal vacuum (and no more or no fewer leaks in the vacuum system). That has VERY little to do with how well the brakes work, but is a rough measure of how much vacuum there is. Marshall -- Marshall Booth (who doesn't respond to unsigned questions) der Dieseling Doktor [EMAIL PROTECTED] '87 300TD 182Kmi, '84 190D 2.2 229Kmi, '85 190D 2.0 161Kmi, '87 190D 2.5 turbo 237kmi
