2nd Gen Non-Engine/Transmission Need advice on brake fluid flushing

[1tuffram]

I finally got around to changing the factory fill brake fluid. The old stuff kind of had a stale smell and I noticed some small "stringy" like stuff floating in the old fluid. Fluid was pretty dark color. When I sucked most out of the master cylinder I have a dark film layer of gunk (sediment ) in the bottom. I do not know how to get this stuff out without stirring it all up and then having it get into the rest of the brake system. I also did not completely remove all the fluid from the master cylinder because I did not want to get air in the system. I did as stated in the article for brake bleeding in issue 30 and left 1/8" fluid in bottom of the reservoirs. What should I do leave it alone or remove all fluid from reservoirs to clean and deal with possibility of getting air in the system. I have 4 wheel ABS and after reading my DC service manual it sounds like a major PIA to bleed air from the 4 wheel ABS system.



The article in issue 30 says to use alcohol to clean the master cylinder out, does it matter which type... . Isopropal (rubbing alcohol) or denautered alcohol.



Finally, I used a mighty vac pump connected to the bleed screws. THe directions said to remove and place teflon tape on the threads to get a good seal for the vaccum to work good. I did this, my question is do I need to remove the teflon tape from the bleed screws now that I'm done?? I don't know if the brake fluid will react with the teflon in the tape and contaminate the system or cause problems. please help

 

[15w40]

Brake Bleeding gone bad

First to answer your question, the teflon tape can stay on the screw. The seal is made by the end of the bleed screw not the threads when it is seated. There is no problem with teflon reacting with brake fluid.



Here is my tale of woe.



This morning I thought I would be nice to my Ram and bleed the old brake fluid. After all, the fluid is almost 4 years old. I started by sucking out the fluid from the brake reservoir and refilling it with some fresh Castrol LMA DOT 4 (a great brake fluid, by the way). I then slid under the rear passenger side to attack the first bleed screw. Using an 8 mm open-end wrench, I noticed that the screw was really tight and the wrench was beginning to round the hex. Not to be defeated by this I grabbed my Craftsman ¼ " ratchet with a 6 point socket to re-attack the stubborn bleed screw. Readjusting the droplight and making sure the socket was fully seated I began pushing on the ratchet handle, feeling confident the screw would yield. As I increased my push, snap, the screw head separated from the threads. I guess the salt laden winters in New England had welded the bleed screw into the cylinder. I am lucky that the fluid did not leak out and I still have brakes. Next spring I will replace the wheel cylinder.



After this experience and thinking about other ways of loosening bleed screws I am looking for some sage advice. I thought about using propane torch to heat the screw but was worried that the rubber parts in the wheel cylinder may get damaged. I also thought about spraying penetrating oil on the screw but I have never had much luck with that. Does anyone have any ideas on loosening these? And when I get them loose would anti-seize be something to use?

 

[illflem]

You don't have to live in New England to get stuck bleed screws, I've had them break off as you did in the salt free arid west. I've found an impact driver (the kind you hit with a hammer) with a 8mm six point will get the tough ones every time, it's the jolt factor. The blue wrench (torch) also works well, I personally use a heat gun, less damage to adjacent areas. No need to worry about seals, you don't need to get the screw that hot. You might be able to remove your broken one with an easy-out, or you might break an easy-out, but your brakes will still work. I've had good luck with a counter clockwise drill bit, it will usually catch and turn the screw out. Might as well use this as an excuse to upgrade to 3500 cylinders, won't cost much more at all, much better stopping power. Anti-seize is a good idea, just keep it off the tip.

 

[BigDaddy]

I am not clear on what you used to "suck most of it out... ", but you might want to try sucking that stuff from the bottom with a Turkey Baster. Just do it after your cook Thursday's meal



I use Speed Bleeders and it takes practically no time at all to change the brake fluid Try em, you'll like em

 

[BK]

The bleeder screws will rust from outside exposure, but most of the time they rust from the moisture traped in the brake fluid.

The brake fluid will settle in the cylinder rusting the pistons in the long run and rusting the bleeder shut.



After freeing them or breaking them and replacing them, you can add teflon tape to help seal them for vacum bleeding and keep the teflon tape on there to help the from rusting up in the future.



Since rubbing alcohol has water added, you don't want to use that for cleaning out the master cylinder...

I believe the denautered alcohol doesnt have water added or other things used for the rubbing process...



Since basic brake fluid is alcohol based, I cant see the harm in doing as you talked about.



I just vacum out my master cylinder every oil change. . and once a year vacum out the whole system and run a quart through it.

 

[1tuffram]

Thanks for the input guys. After my original post I decided to leave the teflon tape on the bleed screws for two reasons, one I had flushed the system until my reservoir was pert near empty and I had run out of fluid to refill. I knew if I took the bleeders off to remove the teflon tape enough fluid would drain out that air would have got into the system. Second it was late, dark and cold out, so I didn't want to hassle with all that and decided to take the car and run to the auto parts store to get more brake fluid to fill the reservoir.



As far as the gunk in the bottom of the reservior... . well my concious got to me and I knew I would not be happy if I left it in there. I sucked as much fluid out as I could and very carefully used paper towels to absorb the remaining fluid out and wipe up the gunk/sediment. I was carefull to leave fluid in the holes in the bottom of each compartment of the reservoir which goes directly into the master cylinder. I was also careful to not get any sediment into the fluid in those holes. Wish I would have known denatured alcohol was the preferred choice to clean the reservoir, I used the only thing I had on hand (rubbing alcohol). I did wipe it dry with paper towels and air dry for a bit before filling with brake fluid. I will keep an eye on the fluid and look for signs of water contamination. I am not sure the cap for the reservoir is sealing properly now that it has been off. After I snapped it on, I could hear air hissing out when pressing down firmly in the middle of the cap. Each time I press down on the middle of the cap I can air hissing. I remember reading an earlier post of people having problems with the caps not sealing properly after being removed for the first time. Just got to love the wonderfully engineered plastic reservoir cap



PS: I sprayed penetrating oil on my bleeder screws and they came out with no problem. I did notice rust/corrosion starting to form on the threads when I removed them to apply the teflon tape.

 

[JoeyD]

I used a phenix injector to push new fluid from the bleeder to the master. I has some thing the call pulse injecting, I don't know, but it pushed all the fluid out and replaced with new. I wasn't shure about air in the lines so after the fliud change I did a old fashion bleed job to be sure. I borrowed the injector from a mechanic friend. Be carefull with it though as I was warned it is expensive. For a frozen bolt try heating te nut with a torch and placing a candel on it after hot and the wax works it's way into the threads.

 

[oldiron]

I also just flushed my system when I upgraded to 1 1/8 bore wheel cylinders. I refilled with Wagner DOT 5. 1 fluid. The can says it is non-silicone, has a 500 degree dry boiling point and is backwards compatible with DOT 3 & 4. Anybody used this before?

 

[Extreme1]

1tuff, You did good. I did the same thing but without the alcohol. The sediment is easily wiped out and you won't need to bleed due to air afterwards.



A tip a mechanic friend of mine gave for stuck bleeders: strike next to the screw with the ball of a ball peen hammer. It will distort the threads enough to break the rust grip but won't cause any problems.



My tip to keep bleeders from rusting: install rubber caps on them! Most replacement calipers come with them.

 

[rweis]

I am bring this old thread up because I did a brake fluid replacement yesterday.



I did not remember about the teflon tape, good idea.



I went to the driver's rear, loosened the bleeder and put a clear hose on it so I could see the fluid color. The brake reservoir fluid was like tea before I started. I gently (by hand) pumped the brake pedal and fluid began to flow out from the driver's rear caliper into the quart catch bottle (the end of the hose in the quart bottle was below the surface of the fluid so air does not get into the system). I pumped it until I had clear fluid (topping off the reservoir fluid with new fluid occassionally).



I did the same thing on all 4 corners. Took almost 3 quarts. Now the brake fluid is all nice and clear and replaced.



Bob Weis



I looked for speed bleeders for a 2002 3500 but could not find any, ideas?

 

[DavidC]

I use the power bleeder pro from these guy's.

http://www.motiveproducts.com/02bleeders.html

Add 2 quarts, open the bleeders one at a time and done in 1 hour or less.



Dave