Comments on bleeding brake lines
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From: Boston North Shore
2001 CLK320 Cabrio
Comments on bleeding brake lines
Have decided to keep my 2001 CLK320 Cabrio, which has provided a very reliable and fun ride for 12 years and 81K miles, until it won't go any more.
So far, the only needed repairs have been the replacement of the MAF at 60K miles (e.g. likely failed due to the dealer tech not installing the air filter properly during the 50K free maintenance period) and a recent CPS failure.
Last year, at 75K miles, even though there were no warning lights, had an indy (prior dealer mechanic) look at factory brake pads and replace as needed. He did the fronts and said the rears were only half worn. Since I was also on the factory fluid, shame on me, I also asked him to replace the brake fluid.
He used a technique of bleeding each cylinder by only gravity (e.g. opening up each bleed value while keeping an eye on the fluid level and adding fluid in the master cylinder).
However, he did not use a dyed replacement fluid, so I'm considering buying some fluid and repeating the procedure (per Marus recommendation of not mixing brake fluid).
I'm very DIY proficient and as I remember the procedure, start at the wheel cylinder furthest from the master cylinder and proceed to the nearest.....correct?
Will also change the transmission fluid. Asked the indy how he does this w/o a drain on the torque converter.
He said, running on the lift gets most of the old stuff out.......comments?
So far, the only needed repairs have been the replacement of the MAF at 60K miles (e.g. likely failed due to the dealer tech not installing the air filter properly during the 50K free maintenance period) and a recent CPS failure.
Last year, at 75K miles, even though there were no warning lights, had an indy (prior dealer mechanic) look at factory brake pads and replace as needed. He did the fronts and said the rears were only half worn. Since I was also on the factory fluid, shame on me, I also asked him to replace the brake fluid.
He used a technique of bleeding each cylinder by only gravity (e.g. opening up each bleed value while keeping an eye on the fluid level and adding fluid in the master cylinder).
However, he did not use a dyed replacement fluid, so I'm considering buying some fluid and repeating the procedure (per Marus recommendation of not mixing brake fluid).
I'm very DIY proficient and as I remember the procedure, start at the wheel cylinder furthest from the master cylinder and proceed to the nearest.....correct?
Will also change the transmission fluid. Asked the indy how he does this w/o a drain on the torque converter.
He said, running on the lift gets most of the old stuff out.......comments?
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From: Glasgow, Scotland, UK
SL 350 R230 (3.7L with AMG Speedshift autobox)
Yes you are right you should start from the furthest brake away from the the cylinder if possible.
A tip is to first remove as much from the brake resevoir as possible first, by using a piece of rubber tube and an old plastic bottle.
Get length of rubber tube like fuel pipe that will fit snuggly onto the 'bleed nipple' of the brakes.
Drill a hole in the lid of the plastic bottle just smaller then the outside diamter of the rubber tube. Then push the tube into the hole for a tight fit and screw the lid to the bottle. Now squeeze the bottle first and then put the open rubber end tube in to the open resevoir and when you let go of the bottle it will draw the fluid up the tube into the bottle, repeat until empty.
Undo your 'Bleed nipple' at the brake (Use a socket rather then a spanner as it gets better purchase, if the nipple is corroded then use a slightly smaller socket and gently tap on with a hammer and use spray to loosen.
Take your same bottle and tube with the oil in it and make sure the tube is below the level of the oil in the plastic bottle (This avoids draw of air back). Now push the open end onto your open nipple stand the bottle up on the ground somewhere and start to pump the brake and stop when all the fluid is out, close nipple. Repeat for the rest.
This method is great because one man can do it and avoids any air trapped.
IF you find the nipple does not open, you can loosen the brake hose where it enteres the brake cylinder but you will need someone to keep the brake pushed down whilst you tighten up to avoid air draw back.
Good Luck
A tip is to first remove as much from the brake resevoir as possible first, by using a piece of rubber tube and an old plastic bottle.
Get length of rubber tube like fuel pipe that will fit snuggly onto the 'bleed nipple' of the brakes.
Drill a hole in the lid of the plastic bottle just smaller then the outside diamter of the rubber tube. Then push the tube into the hole for a tight fit and screw the lid to the bottle. Now squeeze the bottle first and then put the open rubber end tube in to the open resevoir and when you let go of the bottle it will draw the fluid up the tube into the bottle, repeat until empty.
Undo your 'Bleed nipple' at the brake (Use a socket rather then a spanner as it gets better purchase, if the nipple is corroded then use a slightly smaller socket and gently tap on with a hammer and use spray to loosen.
Take your same bottle and tube with the oil in it and make sure the tube is below the level of the oil in the plastic bottle (This avoids draw of air back). Now push the open end onto your open nipple stand the bottle up on the ground somewhere and start to pump the brake and stop when all the fluid is out, close nipple. Repeat for the rest.
This method is great because one man can do it and avoids any air trapped.
IF you find the nipple does not open, you can loosen the brake hose where it enteres the brake cylinder but you will need someone to keep the brake pushed down whilst you tighten up to avoid air draw back.
Good Luck
Last edited by A1EK; Apr 11, 2013 at 04:56 AM.
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Joined: Feb 2013
Posts: 97
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From: South Africa
clk320 and sl320 V6
I like your bottle method, I used to suck the fluid out with a long pipe and my mouth
Will definitely use your way next time.
Another tip but using 2 people is to open nipple push brake slowly down, hold it, then tighten nipple, release pedal slowly and repeat process until all old fluid is pumped out.
And ensure brake reservoir is kept full at all times.
Will definitely use your way next time.Another tip but using 2 people is to open nipple push brake slowly down, hold it, then tighten nipple, release pedal slowly and repeat process until all old fluid is pumped out.
And ensure brake reservoir is kept full at all times.
