Brakes were locking soild
Thread Starter
Newbie
Joined: Oct 2019
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1999 e320
Brakes were locking soild
Bought a clean 1999 E320 but noticed brakes had issue. Were firm but got spongy after about hundred miles. but then ever so slowly they tightened up. Then one day while driving at 55MPH front end started to shake, felt like flat. Got out, nothing got back in and could feel car dragging. with in 1/2 mile the brakes were locked solid no matter how much throttle. Released after couple hours then happened again.
Changed out brake booster after backing off master released pressure. Replaced with rebuilt booster, bled master cylinder and reattached. Now cant bleed back brakes even with vacuum bleeder. Front work but not backs. Is there some kind of proportioning valve on this year E320. Im not finding anything in diagrams. and if there is one how do I check or bleed it? Any advice appreciated.
Changed out brake booster after backing off master released pressure. Replaced with rebuilt booster, bled master cylinder and reattached. Now cant bleed back brakes even with vacuum bleeder. Front work but not backs. Is there some kind of proportioning valve on this year E320. Im not finding anything in diagrams. and if there is one how do I check or bleed it? Any advice appreciated.
MBWorld Fanatic!
Joined: Jan 2009
Posts: 9,225
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From: V E G A S
1922 Ford Model T / no OBD
1. MB require pressure brake flushing/bleeding not vacuum.
2. Locking brakes are due to caliper pistons not returning. I see you did a dozen things on your car, but you did not clean the calipers?
2. Locking brakes are due to caliper pistons not returning. I see you did a dozen things on your car, but you did not clean the calipers?
Thread Starter
Newbie
Joined: Oct 2019
Posts: 2
Likes: 0
1999 e320
sorry, not understanding about the cleaning the calipers comment? I pulled the bleeders out and made sure they were clean. My intent was to flush and replace the brake fluid. Not getting any fluid to rear calipers. Pressure flush you are referring to, is that a pressure fill from the caliper or from the master cylinder.??
MBWorld Fanatic!
Joined: Jan 2009
Posts: 9,225
Likes: 1,798
From: V E G A S
1922 Ford Model T / no OBD
This is the best picture I can find on the net.
When dust boot on the piston gets damaged, dirt and water enters the piston hole and freeze it.
For brake bleeding search the forum. You can buy bleeding pump at any supplier for about $50, or build your own system using spare wheel as pressure source.
When dust boot on the piston gets damaged, dirt and water enters the piston hole and freeze it.
For brake bleeding search the forum. You can buy bleeding pump at any supplier for about $50, or build your own system using spare wheel as pressure source.
