What a great thread.
You should read it through.

Brake flush every two years?! U'r kidding right?



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1985 300SD
1983 300D
2003 Volvo V70

https://www.boldegoist.com/

I've always done mine every 2 years on everything I own, annualy on my bike.

Brake fluid is cheap, replacing corroded calipers and M/C isn't.

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Proud owner of ....
1971 280SE W108
1979 300SD W116
1983 300D W123
1975 Ironhead Sportster chopper
1987 GMC 3/4 ton 4X4 Diesel
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As an alternative, if you don't have the equipment or skills, try replacing the fluid in the reservoir every time you change the oil. Simply suck out the old with a syringe or turkey baster, clean the inside with a lint free towel and replenish with fresh stuff. It's not quite the same as a flush but it'll help.

You don't need any equipment and you don't need any skills.

You need an 8mm wrench for the bleed screws on the calipers, that's it.

If you have a helper, you can get the job done in about 1 hour.

Today, I was replacing calipers and had no helper. So, after I installed the RF caliper, I opened the bleeder and let it run into a jar, while I installed the LF caliper. After about 1 hour, the m/c was down to the low mark. Not the fastest technique, but, I was working on other things in the meantime and figured that the RF wheel can bleed itself during this time.

Tomorrow, I'll speed it up a bit with the easibleed.

I wonder about this. If there are any air bubbles in the system, won't they just keep floating up as the fluid drains? I can't imagaine that air bubbles would just wash downward in that slow-moving stream of draining fluid.

In bleeding the brakes on my airplane the other day, we back-flushed from the caliper up to the master cylinder. It worked great.

A while back, I used a power bleeder on my 300E (attached to the master cylinder) and still had a soft pedal, IMHO because it's hard to flush the air in a downward direction.

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2012 E350
2006 Callaway SC560

Yes, I know that brake fluid should be replaced periodically. For some reason, I have trouble keeping to a schedule on that and have ley my cars go far beyond that ISTS. A viable option, and one that I will do on my MB when I go through the brakes and replace some other compionents is silicone brake fluid. Silicone brake fluid is non-hydroscopic, so it doesn't need to be replaced. It also has a higher boiling point and as you might expect is more expensive.

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'82 300SD - 361K mi - "Blue"

"Good judgement comes from experience. Experience comes from bad judgement."

listen, look, .........and duck.

I, humbly, think you are right. After finishing the job and taking it for a drive, I could swear that there is still some air in the calipers. The pedal travels more than it should and it is softer than it was before the calipers were replaced.

I had attached the Easibleed and used it as well, but, the flow rate is still fairly slow and no air was apparent. Might have to up the pressure or, return to the "two man" method.

This is the way I always bled motorcycle brakes, it is the only way I have had reliable performance from the Mityvac bleeder.

Dieselfan,
Not be argumentative, BUT.....
I don't believe replacing the fluid only in the MC wil do anything. Its a closed-end system. the fluid does not circulate; all the lines are dead ends. Any moisture in the fluid will go to the low point and just lay there. I think actual flushing is the only way to remove this moisture. Replacing the metal lines is no fun.

I try to flush brakes every 25K or few years, you'd be suprised how much better the vehicle stops and the pedal feel is vastly increased.

PM is always good.

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I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG]

AMEN, to that.

I work on to many restorations, show cars and long storage cars, replacing brake lines is a major PIA on any daily driver and H*** on a show car.
Take the time to flush the acid sludge out, it is worth the effort.

This is essential preventive maintenance. To put it bluntly, it is stupid to not do it.

Related thread here, includes how to economically build a power bleeder from a garden sprayer.

Power Bleeder or what?

You're exactly right. The new fluid in the MC would just push down on the old fluid with no mixing occuring.

Cheers,

Bill

Hi Kevin.

I was being somewhat serious, but failed to include that a significant part of the decision making process should be reading, understanding and following the Owner's Manual, usually found in the dusty shelves of a Public Library.

Whunter makes the excellent point that the OMs define different types of service, and adjust recommended service intervals accordingly.

As you observed that the 'average' owner understands the 3 month/3,000 mile oil change interval (one-size-fits all) without realizing that this is usually for Severe Service, because they have no knowledge that there is such a thing as Severe Service, and it's probably just the opposite of what they think.

Some will rely on their indy or dealer for advice. As such, how many dealers or independent services will recommend a brake fluid change? (Show of hands?)

On a side note, all of my car crashes have been due to judgement failure, not mechanical failure. Of course there was one flat tire on a motorcycle, not due to underinflation or tread depth, that left me pretty busted up laying in the median of a Detroit freeway ...

I am in favor of changing the brake fluid, as well as other maintenance.

Very interesting thread.

Jim

From the For What It's Worth department:

http://www.csaa.com/global/articledetail/0,1398,1004010302%257C2026,00.html

What caught my eye? Taken from one paragraph,

"Vehicle manufacturers are about evenly divided on whether or not the brake system should be flushed periodically and refilled with fresh fluid."

"All of the manufacturers who call for brake fluid changes are import carmakers, about evenly divided between Asian and European.

"None of the domestic Big-Three manufacturers calls for periodic brake fluid changes."

So, I conclude that each of us can, and should decide for ourselves... :p

Best Regards,
Jim