teflon tape and bleeder screw threads?

[00 scrub]

I have been told opposite things about the value and danger of putting teflon tape on the threads of my brake bleeder screws. I have read in Popular Mechanics and been told by other people that putting teflon tape onto the threads (in order to prevent any air being drawn into/out of teh system when bleeding) that the teflon can come apart and flow through your system and eventaully clog ABS valves and whatnot. Other have said it is ok and that since the fluid is only applying pressure one way it shoudln't matter.
But wouldn't the suction of the master cylinder returning to normal position when you let off the brakes evenutally move the pieces of teflon up?

BTW we are bleeding with a mighty-vac thing that you hook up to an aircompressor and it sucks out the fluid.

 

[labman]

Unless you are bleeding by running the fluid through a hose into a container of brake fluid, there should never be any fluid flowing in the bleeder when it is open. Otherwise, I don't see Teflon tape as being a problem. It should be very effective in preventing frozen bleed screws.

On the other hand, a good coat of silicone grease on the bleed screw fixes that and reduces corrosion too, with no danger of an errant bit of Teflon.

 

[jthorner]

Teflon tape works ok as long as you make sure to not get the tape at the tapered seat working end, but only on the upper threads. I used to use the Mityvac style bleeder and teflon tape trick, but I have switched to a pressure systems and it is much better! The one I'm using is from www.motiveproducts.com .

John

 

[porterdog]

quote:

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Originally posted by 00 scrub:
...putting teflon tape onto the threads (in order to prevent any air being drawn into/out of teh system when bleeding) that the teflon can come apart and flow through your system and eventaully clog ABS valves and whatnot.

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Bul*cr*p. There is no 'circulation' in a brake system; the only true flow is from the res to the wheel cylinders, and that is miniscule because it's only enough to compensate for brake pad wear.

Agree with JT though- if one were to get it over the seat/port of the bleeder that could be Bad.

 

[n8wvi]

You fellas are making bleeding too difficult/expensive. Ever hear of gravity? It's all I've ever used, it can be done w/ one person, and it's FREE.

Dave

 

[RavenTai]

Not all systems will gravity bleed and it takes a long time, also gravity bleeding is not reliable for removing air good for exchanging fluid in an air free system though

 

[00 scrub]

Man this argument is exactly the opposite of what I got whe nI posted this question over on www.grmotosrports.com . I guess I'll just go the safe route and not teflon tape them and live with the worse bleed.

BTW the might-vac system I am using isn't the usually hand pump mighty-vac. It is a system that sucks the air through by blowing air from an air compressor across a fan and creating a suction. This suction sucks the brake fluid from the bleeder nipple. It is pretty much hands off.

 

[Kestas]

The only time I use gravity bleeding is after major brake work such as line replacement, where there's a lot of air in the system. This constitutes a rough-bleed, and gets rid of most of the air which is compressible and messes with pedal-bleeding. The bleeding can then be continued conventionally with the brake pedal, though a lot of times I find the gravity bleed removes the air completely.

 

[Smoky14]

I've found over the years that the best method, for hard to bleed systems, is reverse pressure bleeding. Air wants to go uphill so if fluid is put in at the bleeder port and removed at the master reservoir most all the air is removed.

Just a suggestion

 

[labman]

quote:

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Originally posted by Smoky14:
I've found over the years that the best method, for hard to bleed systems, is reverse pressure bleeding. Air wants to go uphill so if fluid is put in at the bleeder port and removed at the master reservoir most all the air is removed.

Just a suggestion

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Hummmm, I wonder if that would work on a tilt cab Ford? I would be very careful to remove any dirty or damp fluid at the caliper first. Of course, if the bleeding is following a rebuild/replace, all the crud is gone. Actually I question how much bleeding in either direction disturbs the crud at the bottom of a caliper or wheel cylinder.

I have read not to force fluid back through an ABS. However, it happens every time you release the brake pedal. Maybe it is ok to do it slowly.

Getting back to the Teflon tape. Even if you did manage to plug up the bleed screw with it, at least it would be easy to remove and clean it, unlike other parts of the system.

As for those plugged bleeders, I would be very surprised to find the ball check ones still working when you went back after a year or 2.

One more point. The old codger I worked for at the brake shop was dead set against using Teflon tape in an air brake system. Too easy for a small piece of uncleanable material to get in the wrong little passage.

 

[00 scrub]

Whoops, I'm dumnb here is the proper link:

http://www.grmotorsports.com/

http://www.grmotorsports.com/board/viewtopic.php?t=4162

Well now there is one person that agrees with you.

 

[dkcase]

quote:

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Originally posted by 00 scrub:
Man this argument is exactly the opposite of what I got whe nI posted this question over on www.grmotosrports.com . I

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What was that link again ??
Somehow it's spelled wrong; I made a couple guesses that also didn't work. grmotorsports ? gomotorsports ?

 

[ChrisW]

quote:

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Originally posted by Kestas:
The only time I use gravity bleeding is after major brake work such as line replacement, where there's a lot of air in the system. This constitutes a rough-bleed, and gets rid of most of the air which is compressible and messes with pedal-bleeding. The bleeding can then be continued conventionally with the brake pedal, though a lot of times I find the gravity bleed removes the air completely.

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whe you gravity bleed, are you supposed to have only one bleeder screw open at a time, or can you have two?

I've done gravity bleeding before, and it takes forever, really.

 

[Kestas]

I guess it depends on the car. Mine certainly didn't take forever. A few minutes perhaps. I've only opened one bleeder at a time. I only have one line/container assembly. I suppose you could have more than one open at a time.

 

[n8wvi]

If I have enough 'things' to catch the fluid in, I open all 4. Just be sure to not let the resivoir go dry.

Dave