brake fluid questions

[chopchop]

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by hover_one:
......The mechanic said he was afraid to do it because it looked like sludge, and was afraid it had never been done, he was afraid he would cause more damage by putting in new stuff...

<hr></blockquote>

He's not much of a mechanic, then! So what's his idea? Do nothing...?
The job NEEDS doing - doing nothing is not an option.

- Richard P

[ December 16, 2001: Message edited by: chopchop ]</p>

 

[GoFaster]

How can changing the brake fluid cause something else to go wrong?

This is an easy do-it-yourself job if you have a brake fluid bleeding device (Mityvac, or something similar). If you don't have such a gadget, it's still an easy job, but you need a second person on the brake pedal ... "Press" ... open bleeder valve, close bleeder valve, "Release" ... 1 second delay ... repeat until clear fluid comes out, periodically refilling the reservoir, then do it all again at the next corner until you've done all 4. Doesn't take as long as the description suggests.

 

[hover_one]

While I was out of town, the wife took my Passat in, and I asked her to get the brake fluid changed--first time since I've owned it.

The mechanic said he was afraid to do it because it looked like sludge, and was afraid it had never been done, he was afraid he would cause more damage by putting in new stuff...

The job nees to be done. What questions should I ask, things i should warn him about, or things I should be concerned with? Is he over-cautious or just not as knowlegeable as he ought to be?

Thanks!
Hover

 

[hover_one]

This is a second-hand report from my loving wife, who does not do well with mechanics. I think the guy is afraid of knocking loose some crud that will float into something critical and cause a problem that he will get blamed for. I'm going to get the job done, I was just wondering if anyone had any ideas about things I should be careful of.

Thanks to all!

hover

 

[chopchop]

Suck the old fluid out of the m/c reservoir first (with a turkey baster - cleanliness paramount), then refill the reservoir with fresh fluid (minimises the volume of contaminated fluid you're pumping through the system), then just pump/pressurise all the old crap through until you have new, clean fluid exiting from each bleed nipple. Don't economise on new fluid - it's cheap enough! There's no other way. Good luck!

 

[Drivbiwire]

The onl;y hang up I can see with this job since the brake system has been neglected for so long is the bleeder valves may be rusted into position. If this is the case then the calipers would have to be removed and the old bleeder valve drilled out and replaced (can't be done on the car).

However if he soaks the valves with some good quaility penetrant before hand and allow it to soak in the job may go very quickly and easily.

This excuse that it may case something to fail is plain ignorance. Leaving that old fluid in the system WILL cause something to go bad (he must be a chevy mechanic).

One thing that is important to stress since your mechanic has already demonstrated a lack of sytem knowlege, is you/he MUST use a DOT4 fluid not DOT3! There are several fluid available from most any auto parts store. The stuff I use is the valvoline Synpower DOT3/4 brake fluid. It costs about $4.80 for 32 oz and is usually enought to do the whole system.

One thing that I do when changing brake fluid is suck all the fluid out of the reservoir, remove it and clean out all the old residues. This way there is nothing left that can contaminate the brand new dry fluid. Also it allow me to look into the reservoir and determine the color. It very very easy to remove it simply has two lip seals and two side straps to prevent the reservoir from coming loose.

While the system is being flushed make sure they also bleed the clutch slave cylinder since it gets it fluid supply from the brake reservoir.

In the future if you see the fluid taking on a color anything other than clear have it changed. This is a good indicator that the fluid is absorbing water and rust has formed in the system. The object of the game is to never have to replace any brake system component, therefore always keep the fluid as clear as possible by having it changed on a regular basis.

If the fluid is as brown as you say consider having it replaced again in the spring just to make sure that all the water in the system has been absorbed.

I have found that I need to replace my fluid at every brake pad change or once a year due to the discoloration of the fluid. This may be overkill but the fact is the fluid is cheap and I have the $40.00 brake fluid bleeder (worth every penny!!!).

If you lived close to me I'd tell you to stop over.

DB

[ December 17, 2001: Message edited by: Drivbiwire ]</p>

 

[Doug Huffman]

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by GoFaster:
How can changing the brake fluid cause something else to go wrong?<hr></blockquote>

On the fourth visit to a stealership for the 30K service I found, finally, evidence that more than an oil change was done. While wiping around under the engine cover, as I occasionally do for cleanliness and to familiarize myself with component locations, I noted that the Brake Fluid Reservoir Level Switch connector was broken. Evidently the connector was used to increase torque or grip on removing the reservoir top. Now the distal portion of the switch, where I imagine the strain relief is, hangs by the wires from the body of the connector.

And the stealership is too cheap and dishonest to admit the error and change the connector. It's no damn wonder people don't trust nuclear power. Had I found this workmanship in a reactor plant, the critique would still be going on.

 

[Hollywood]

You can do this yourself without any fancy tools. Get an empty plastic 2-litre cola bottle. Get two feet of clear vinyl hose 1/4" ID. Ream a hole in the lid of the bottle and jam the hose in. Jack car up and remove wheel(s). Place free end of hose on bleeder valve such that the hose makes a loop up and back down to the bottle. Loosen bleeder and pump brake pedal. The fluid in the hose keeps you from sucking air. Cost maybe $1.