Lets have a brake / clutch cylinder bleed / flushing party!

[ricosuave]

I'll bring the 4L of Castrol GT LMA synthetic, 2 jackstands and a hydraulic lift and my assistance...
http://www.castrol.com/liveassets/bp...BrakeFluid.pdf

You bring your mityvac or motive or other fluid vacuum, experience in doing this, and of course, your mk4.

I have 2 cars that need to be done, have enough fluid for 2 more. Dont really want to hang on to 2L of opened brake fluid.

Any takers?

[Stonewall]

Re: Lets have a brake / clutch cylinder bleed / flushing party!

Wish I had a mity vac. I am use to doing it the old way though otherwise I would help you out.

[stefan]

Re: Lets have a brake / clutch cylinder bleed / flushing party!

the motive ones are cool. almost ordered one last year.

[Khyron]

Re: Lets have a brake / clutch cylinder bleed / flushing party!

Just a bump since I just ordered the Motive power bleeder and will be doing this next warm-ish weekend if anyone else wants to do it at the same time.

[jiggseob]

Re: Lets have a brake / clutch cylinder bleed / flushing party!

Me too!!! I did this a few months ago, starting by pumping a quart of dot3 through the brake system of my old A2. Then I got a gallon of Dot4 and did my 98 Beetle and Wife's 03 Jetta and the neighbours 02 Golf. That still left me with a good half gallon. My experience is that the gallon (4.4 litre Imperial gallon) will do about 5 cars.

http://forums.tdiclub.com/showthread.php?t=294218

is the link to my home-made pressure bleeder. It really does work well. The "baster" thing they talk about is a 100cc syringe, used to suck as much old brake fluid out of the master cylinder reservoir, and then filling master cylinder reservoir from the can with clean fluid, before starting the pressure bleed process. That really does make the process quick. You can get a syringe from a farm supply or veterinary store, you also need to buy a needle to put on the syringe, could be a couple bucks. As an alternative to a needle for the syringe, you can sometimes use a 1/8" piece of hose pushed onto the needle spigot of the syringe. The syringe is cheap plastic, and after a bath in brake fluid the plastic and rubber may break down in a few days.

I put the brake fluid in the garden sprayer. When you connect the sprayer to the brake system and presure it up, the whole brake system is pressured up to the pressure in the sprayer. But no fluid will move until you let something out, such as by opening a bleed screw. Then, fluid moves out the bleed screw and if the pickup tube in the sprayer is immersed in fluid, fluid moves out of the sprayer into the master cylinder reservoir. Any air trapped in the master cylinder reservoir will stay right where it is, and not move through the system.

Its amazing how much the pedal pressure firms up from bleeding, there must get tiny bubbles in there some how during years of normal driving.

I'm about 3.5 hours from Calgary, otherwise I'd crash your brake bleeding party - it sounds like fun. Its -35C here this AM, not the kind of weather to have a brake bleeding party in the driveway...

All the best guys,

Jiggs
Round Hill, AB

[BaggedGLI]

Re: Lets have a brake / clutch cylinder bleed / flushing party!

Hey Geoff,

I need to do mine as well, BADLY, let me know when it comes in, I've got a heated garage, and a fridge with beer.



Jiggs, yeah, the syringes are toast after a day, the brake fluid just eats the seal. I've heard of people using a turkey baster.

[Khyron]

Re: Lets have a brake / clutch cylinder bleed / flushing party!

Ordered it on Fri from the US, so next week anytime I would guess. After mine is done anyone can borrow. I got the air tools/attached garage so it should be ok for a few people to come by.

[Stonewall]

Re: Lets have a brake / clutch cylinder bleed / flushing party!

I used a motive bleeder today when I did the brakes on the van, it sure makes the job a hell of a lot easier. Just be sure to not over pressurize the tank (10psi should do), well unless you like blowing the seals out of your master cylinder.

[Khyron]

Re: Lets have a brake / clutch cylinder bleed / flushing party!

Did you also put a block of wood under the brake to prevent it bottoming out? I read that tip for older cars.

[jiggseob]

Re: Lets have a brake / clutch cylinder bleed / flushing party!

Over the course of years, the brake fluid takes on water, and starts corroding the interior surfaces of the brake system. One surface that gets some scale on it is the inside of the master cylinder. During normal brake operation, the piston in the master clinder keeps the normal travel area all shined up, but the deep-pedal travel area where the piston does not normally travel gets a scale build-up.

During brake bleeding, if the full stroke of the pedal pushes the piston into an area of the master cylinder that is scaled, the piston o-rings will be ruined.

Thats why sometimes a car goes in for service, and the brakes are fine. Service manager says "car is 10 years old, it should have brake fluid changed". One thing leads to another, and it ends up being a master cylinder change. Ka-ching, and annoyance on part of customer, thinking service guys are scamming...

Using a block on the floor would serve to limit pedal travel to the normal stroke area.

Using a pressure bleeder will move the fluid without moving the master cylinder piston.

The inside of the brake system will hold hundreds if not thousands of psi pressure. The o-rings holding the plastic reservoir to the master cylinder will only hold a few psi. If that fails, the failure will be obvious. The seal around the brake pedal pushrod will also only hold a few psi. If that fails, the indicator is brake fluid dripping on the drivers feet.

Jiggs.

[Stonewall]

Re: Lets have a brake / clutch cylinder bleed / flushing party!

^ what he said never touched the pedal other then to seat the brakes after changing the rotors and pads.