Mercedes SLK World banner
  • Hey Everyone! Enter your ride HERE to be a part of this months Ride of the Month Challenge!
Status
Not open for further replies.
1 - 20 of 31 Posts

·
Registered 2005 SLK55 AMG
Joined
·
619 Posts
Discussion Starter · #1 ·
I see that we have one post where a member did this himself but not many others. I'm just curious how many members have done this job themselves vs. having the dealer do it.

I was just planning on having the dealer do this when I bring the car in at 20,000 miles in a few weeks, but I have to replace the brake lines and fluid on my '99 BMW too and between the both cars, I'll save a bundle if I do it myself (MB is $170 for the flush). I have to admit that I don't think the BMW has ever been done (10 years / 85,000miles) but the fluid in the SLK looks as clean as can be. I'm sure the previous owner had it done at 2 years.

Any concerns anybody has about doing this job yourself? ATE seems to be the high end fluid of choice for BMW's - how about Mercedes?
 

·
* Founding Member #2
2008 SLK55 AMG
Joined
·
19,485 Posts
From the approved fluids list from MB: MB Part No. A000 989 08 07 01, also Mobil Brake Fluid DOT 4 Plus.
 
  • Like
Reactions: garylight

·
Premium Member
Joined
·
3,248 Posts
There are two methods to exchange brake fluid; one is to force-feed fluid from the master cylinder reservoir through the system and out of the bleeders on the calipers. The other is to use vacuum to pull it out of the caliper.
This is not model specific; but this is how I exchange the fluid in a brake system.
I use a vacuum pump brake bleeding system; it consist of a hand operated pump and an inline reservoir.
The preferred way:
Place car on jacks and remove tires.
Open the master cylinder reservoir and, using the vacuum pump, remove all fluid and refill.
If the reservoir contains sediments:
Refill the reservoir with clean fluid; agitate the fluid to suspend sediments, and empty again.
Refill the reservoir and agitate again, if sediments are visible empty again.
Repeat until the fluid remains clear.
Note: Most brake fluids will damage your paint; if you spill any, clean it up!
Many manufactures give a brake bleeding sequence; in reality it is not very important, but I like to start with the brake furthest from the master cylinder ending up with the closest.
To me, the next step is important: to prevent from ‘back flushing’ any dirty fluid, fist attach the vacuum pump to the bleeder, open the bleeder and pull about halve the amount in the master cylinder reservoir in to the inline reservoir.
Refill the master cylinder reservoir.
With the bleeder still open, and, using a proper tool, force the caliper pistons in to the fully retracted position.
Using the vacuum pump pull fluid in to the inline reservoir until it appears clear.
Important: Keep refilling the master cylinder reservoir to prevent air from entering the system.
Go to the next brake, attach the vacuum pump, open the bleeder, force the pistons back, pull fluid until clear… and so on.
Note: I will always return to the fist brake and repeat, if the fluid is clear I’m satisfied, if not I will go around again.
Important: After you are finished and all bleeders are secured, pump the brakes until pressure builds up; check the master cylinder reservoir and fill to the ‘Max’ Line.
The quick way:
Clean the master cylinder reservoir as above:
Select your first brake, attach the vacuum pump, pull fluid until clear; repeat for the remains brakes.
This will be as good, or better, as any shop will do for you.
 

·
Registered 2005 SLK55 AMG
Joined
·
619 Posts
Discussion Starter · #4 ·
Thanks for the insight PropDr. The pressure bleeders seem to be very popular (ie Motive) as well. Along the same lines as the vacuum idea except you are pushing the brake fuild through rather than sucking it through. Not sure if that makes a big differnce but I like the concept.
 

·
Premium Member
Joined
·
3,248 Posts
Thanks for the insight PropDr. The pressure bleeders seem to be very popular (ie Motive) as well. Along the same lines as the vacuum idea except you are pushing the brake fuild through rather than sucking it through. Not sure if that makes a big differnce but I like the concept.
The effect is the same (as long as the reservoir is cleaned first) but if anything goes wrong during pressurization, there will be brake fluid all over the place.
 

·
*Registered
2008 SLK55 AMG
Joined
·
467 Posts
When bleeding always start at the wheel furthest from the reservoir and then the next furthest.

For most cars it will be:

Passenger rear
Driver Rear
Passenger front
Driver front

I haven't had my ride that long but I'm assuming it's in front of the driver on a brake booster.
 

·
*Premium Member; DAS/STAR Reg'd Owner
2004 SLK200
Joined
·
285 Posts
Have you ever tried the 2 man method in the SLK?

Thanks!
 

·
Registered
Joined
·
659 Posts
I've done the 2 man method for years however it just isn't worth it anymore when you can get a $5 brake bottle from the autoparts store and you don't need the "up.. up... down.. down" second man. Hook it on, pump it several times, take it off and dump it. Next wheel.

I find the 'pressure way' the easiest though. I bought a pressure bleeder a couple years back and wondered why I didn't do it sooner.
 

·
Registered
Joined
·
1,139 Posts
When bleeding always start at the wheel furthest from the reservoir and then the next furthest.
This was the advice prior to the days of ABS and traction control.

Now, each wheel has its own dedicated line from the ABS unit, and order of bleeding is meaningless. There is no "T" in a single line to the rears, for example.

In fact, WIS AR42.10-P-0010V, Bleed brake system," specifies do fronts first and doesn't specify side order.

In addition it seems prudent to finish by bleeding the clutch slave cylinder on manual transmission cars as the WIS instruction instructs.
 

·
Premium Member-gave my 2003 SLK320 to my daughter
Joined
·
1,321 Posts
The service CD for my '03 suggests the order is right rear, left rear, right front and left front. The CD doesn't say you must do it in that order, but that's the order the directions lead you.
 

·
*Premium Member; DAS/STAR Reg'd Owner
2004 SLK200
Joined
·
285 Posts
Thanks, I'll look into the WIS instructions to understand how to bleed the clutch slave cylinder as my car is manual transmission.

But if I'm not mistaken there is an order to bleed the brakes, in one of the generic documents on WIS... but it is not important I'll just do it in the RR, RL, FR and FL and if there isn't a order this is as good as any. :)

Best Regards!
 

·
Registered
Joined
·
579 Posts
"...ATE seems to be the high end fluid of choice for BMW's..." This is true of BMW CCA members in general. They are anal about flushing brake fluid and ATE is available in two different colors to alternate. This makes it a bit easier to see when all old fluid has been purged. Any DOT 4 fluid is OK.

I see that we have one post where a member did this himself but not many others. I'm just curious how many members have done this job themselves vs. having the dealer do it.

I was just planning on having the dealer do this when I bring the car in at 20,000 miles in a few weeks, but I have to replace the brake lines and fluid on my '99 BMW too and between the both cars, I'll save a bundle if I do it myself (MB is $170 for the flush). I have to admit that I don't think the BMW has ever been done (10 years / 85,000miles) but the fluid in the SLK looks as clean as can be. I'm sure the previous owner had it done at 2 years.

Any concerns anybody has about doing this job yourself? ATE seems to be the high end fluid of choice for BMW's - how about Mercedes?
 

·
Premium Member-gave my 2003 SLK320 to my daughter
Joined
·
1,321 Posts
Don't go by the color of brake fluid telling you if it's good or not. You can probably tell when the fluid looks bad enough to change, but just because the fluid might look good, doesn't mean that it is. Might be clean, but the water content may exceed the acceptable limit. That's why the every two year service is required.

Len
 
  • Like
Reactions: PropDr

·
Registered
Joined
·
1,139 Posts

·
Registered
Joined
·
579 Posts
I think we are talking about different things. I apologize for not making my post absolutely clear with respect to ATE brake fluid. I was not talking about judging the performance capability of brake fluid by it's color.

I was trying to convey the reason/justification for ATE's two different color dyes. The differentiation is intended to indicate when all the old fluid has been replaced in the brake hydraulic system by new fluid, regardless of it's age or condition. Hope this helps.

Don't go by the color of brake fluid telling you if it's good or not. You can probably tell when the fluid looks bad enough to change, but just because the fluid might look good, doesn't mean that it is. Might be clean, but the water content may exceed the acceptable limit. That's why the every two year service is required.

Len
 

·
Premium Member-gave my 2003 SLK320 to my daughter
Joined
·
1,321 Posts
I think we are talking about different things. I apologize for not making my post absolutely clear with respect to ATE brake fluid. I was not talking about judging the performance capability of brake fluid by it's color.

I was trying to convey the reason/justification for ATE's two different color dyes. The differentiation is intended to indicate when all the old fluid has been replaced in the brake hydraulic system by new fluid, regardless of it's age or condition. Hope this helps.
I understood that Ben. Using different colors is not a bad idea. What I was referring to was the comment above about how the brake fluid looked good even though the owner had no idea how old it was.

Len
 
  • Like
Reactions: ben721364
1 - 20 of 31 Posts
Status
Not open for further replies.
Top