[MBZ] Brakes and other deferred maintenance
I just got done jacking up the newly acquired POS 300E and getting under it as part of assessing its immediate needs prior to placing a Rusty order. Took the back left wheel off first because it was making awful scraping noises every time I hit the brakes. I have never seen pads with so little pad left on them, nor a rotor with such an uneven surface. Yikes. That explains it. One funny thing: turning the same wheel by hand (with the shifter in neutral and the parking brake off) produced a very faint version of the same metal-on-metal scraping sound. Dragging caliper? It seemed like the wheel offered a normal amount of resistance to being spun by hand. I could have put the other 124 up in the air and compared the two side-by-side, but I was too lazy to play musical jackstands. Bad bearing? Dry differential? (It's visibly leaking, who knows for how long.) Alex Chamberlain '87 300D Turbo, '86 300E, et al. ___ http://www.okiebenz.com 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://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Brakes and other deferred maintenance
Congrats, you're now a man of many W124s. :-) Not sure about the sound or calipers, well, for a W124 yet. And it's not the wear sensor on the pad itself dragging? Maybe the pistons in the calipers are just so extended out,the pad or what's left is a little misalighned? Just guesses, as have had to do much on mine yet, but a Spring tune up is in the works soon. Have fun with the new car. Ed 300E On 17/04/2008, Alex Chamberlain [EMAIL PROTECTED] wrote: I just got done jacking up the newly acquired POS 300E and getting under it as part of assessing its immediate needs prior to placing a Rusty order. Took the back left wheel off first because it was making awful scraping noises every time I hit the brakes. I have never seen pads with so little pad left on them, nor a rotor with such an uneven surface. Yikes. That explains it. One funny thing: turning the same wheel by hand (with the shifter in neutral and the parking brake off) produced a very faint version of the same metal-on-metal scraping sound. Dragging caliper? It seemed like the wheel offered a normal amount of resistance to being spun by hand. I could have put the other 124 up in the air and compared the two side-by-side, but I was too lazy to play musical jackstands. Bad bearing? Dry differential? (It's visibly leaking, who knows for how long.) Alex Chamberlain '87 300D Turbo, '86 300E, et al. ___ http://www.okiebenz.com 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://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com 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://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Brakes and other deferred maintenance
turning the same wheel by hand (with the shifter in neutral and the parking brake off) produced a very faint version of the same metal-on-metal scraping sound. Dragging caliper? Pads in or out? If out, it can't be that, in which case I'd first suspect the parking brake shoes. Pop off the drum/disc and have a look. -- Jim ___ http://www.okiebenz.com 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://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Brakes and other deferred maintenance
Disc brake pads do drag very slightly at all times. The pads do not pull back when you release the brake pedal, they just stop squeezing. Allan -- 1983 300D On Thu, 17 Apr 2008 00:02:03 -0700, Alex Chamberlain [EMAIL PROTECTED] said: I just got done jacking up the newly acquired POS 300E and getting under it as part of assessing its immediate needs prior to placing a Rusty order. Took the back left wheel off first because it was making awful scraping noises every time I hit the brakes. I have never seen pads with so little pad left on them, nor a rotor with such an uneven surface. Yikes. That explains it. One funny thing: turning the same wheel by hand (with the shifter in neutral and the parking brake off) produced a very faint version of the same metal-on-metal scraping sound. Dragging caliper? It seemed like the wheel offered a normal amount of resistance to being spun by hand. I could have put the other 124 up in the air and compared the two side-by-side, but I was too lazy to play musical jackstands. Bad bearing? Dry differential? (It's visibly leaking, who knows for how long.) Alex Chamberlain '87 300D Turbo, '86 300E, et al. ___ http://www.okiebenz.com 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://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com 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://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Brakes and other deferred maintenance
On Thu, Apr 17, 2008 at 6:39 AM, Allan Streib [EMAIL PROTECTED] wrote: Disc brake pads do drag very slightly at all times. The pads do not pull back when you release the brake pedal, they just stop squeezing. Thanks Allan, I don't know why I didn't know that. That makes sense since there is practically no pad left---the backing plates must just be dragging and scraping a tiny bit. Jim---the old pads are still in, but I will check out the parking brake as well as long as I have the rotors off. I've already ordered new ones from Bimby but would like to take the old ones to the machine shop if possible and keep them for spares. I remember there being a controversy at some point on whether Mercedes rotors can be turned or not---what was the conclusion? I know Marshall, bless his soul, had a STRONG OPINION one way or the other but I don't remember what it was. ;) Ed---when you get around to doing brakes on your 300E you will see that early 124s don't have wear sensors on the rear pads, only the fronts. Also, if the front wear sensors are dragging they don't make any noise---they just make the idiot light flicker annoyingly. I know because my 300D has been doing that for a long time (light intermittent despite plenty of pad left in the front) and I just haven't got around to changing them yet. Alex Chamberlain '87 300D, '86 300E, et al. ___ http://www.okiebenz.com 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://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Brakes and other deferred maintenance
Look up the minimum thickness spec for the rotors. Measure them. Are they already thinner than spec? If not, estimate the depth of the grooves (both sides) and subtract that, I bet you're well under spec by then. ___ http://www.okiebenz.com 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://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Brakes and other deferred maintenance
I remember reading an article about a competition to get the best fuel mileage. One of the things suggested was that one should move back and forth a bit after using the brakes in order to let the little bit of play in the bearings essentially move the pads off of the rotor. Not sure how well that works. Randy -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Allan Streib Sent: Thursday, April 17, 2008 7:40 AM To: Mercedes Discussion List Subject: Re: [MBZ] Brakes and other deferred maintenance Disc brake pads do drag very slightly at all times. The pads do not pull back when you release the brake pedal, they just stop squeezing. Allan -- ___ http://www.okiebenz.com 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://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Brakes and other deferred maintenance
Thanks Alex, my Spring inspection and tune up is coming up soon. :-) Now where did I leave those axle stands?? Ed 300E On 17/04/2008, Alex Chamberlain [EMAIL PROTECTED] wrote: On Thu, Apr 17, 2008 at 6:39 AM, Allan Streib [EMAIL PROTECTED] wrote: Disc brake pads do drag very slightly at all times. The pads do not pull back when you release the brake pedal, they just stop squeezing. Thanks Allan, I don't know why I didn't know that. That makes sense since there is practically no pad left---the backing plates must just be dragging and scraping a tiny bit. Jim---the old pads are still in, but I will check out the parking brake as well as long as I have the rotors off. I've already ordered new ones from Bimby but would like to take the old ones to the machine shop if possible and keep them for spares. I remember there being a controversy at some point on whether Mercedes rotors can be turned or not---what was the conclusion? I know Marshall, bless his soul, had a STRONG OPINION one way or the other but I don't remember what it was. ;) Ed---when you get around to doing brakes on your 300E you will see that early 124s don't have wear sensors on the rear pads, only the fronts. Also, if the front wear sensors are dragging they don't make any noise---they just make the idiot light flicker annoyingly. I know because my 300D has been doing that for a long time (light intermittent despite plenty of pad left in the front) and I just haven't got around to changing them yet. Alex Chamberlain '87 300D, '86 300E, et al. ___ http://www.okiebenz.com 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://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com 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://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Brakes and other deferred maintenance
May well be that something is frozen, perhaps the handbrake is not fully retracting. Best of to strip the brakes off and then do the turny test to see if it is bearings or brake related. If the diff is leaking it means there is oil in there, the only time a MB diff will not leak is when it is out of oil. Hendrik with a leaky diff or two E M wrote: Congrats, you're now a man of many W124s. :-) Not sure about the sound or calipers, well, for a W124 yet. And it's not the wear sensor on the pad itself dragging? Maybe the pistons in the calipers are just so extended out,the pad or what's left is a little misalighned? Just guesses, as have had to do much on mine yet, but a Spring tune up is in the works soon. Have fun with the new car. Ed 300E On 17/04/2008, Alex Chamberlain [EMAIL PROTECTED] wrote: I just got done jacking up the newly acquired POS 300E and getting under it as part of assessing its immediate needs prior to placing a Rusty order. Took the back left wheel off first because it was making awful scraping noises every time I hit the brakes. I have never seen pads with so little pad left on them, nor a rotor with such an uneven surface. Yikes. That explains it. One funny thing: turning the same wheel by hand (with the shifter in neutral and the parking brake off) produced a very faint version of the same metal-on-metal scraping sound. Dragging caliper? It seemed like the wheel offered a normal amount of resistance to being spun by hand. I could have put the other 124 up in the air and compared the two side-by-side, but I was too lazy to play musical jackstands. Bad bearing? Dry differential? (It's visibly leaking, who knows for how long.) Alex Chamberlain '87 300D Turbo, '86 300E, et al. ___ http://www.okiebenz.com 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://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Brakes and other deferred maintenance
Disc brake pads do drag very slightly at all times. The pads do not pull back when you release the brake pedal, they just stop squeezing. They do pull back, a tiny bit, due to the O-ring (square cross-section) puck seals. But they usually still drag a little, in part because the pad is free to lean against the rotor if it likes. shop if possible and keep them for spares. I remember there being a controversy at some point on whether Mercedes rotors can be turned or not---what was the conclusion? They _can_ be turned, but they should not be unless they are grossly damaged _and_ are not already too thin. Minor ridging is not a problem, new pads will bed to it, and in fact may even brake better because there is more surface area. -- Jim ___ http://www.okiebenz.com 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://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
