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Teflon tape on bleed screws

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Just a quick question for you guys who use teflon tape on brake bleed screws. Do you wrap all the threads with it or just part way down? Im concerned about it coming off the lower threads and fouling up the wheel cylinder.
Thanks,
jv
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I have used this method many times with no problems. Knowing that using teflon tape on systems where it is not good for the tape to enter, I take care to use only enough tape to seal the threads, and preferrably at the top, as you noted. Another, but messy method is to use RTV on the threads--really messy.
 
I cut the tape lengthwise so it is about 3/16" wide. Since one would rarely remove the bleed screw unless doing a rehab of the cylinder or caliper, being conservaitve with the tape may be enough to avoid getting anything into the system.
 
Geo,
Your previous post on cutting the tape down the middle is what got me thinking about that. Half the threads are shiney and the other half are soiled from being exposed. Should I take the tape 1\2 way down the shiney threads or is that to far?

Jayarbee,
I try to stay away from blue rtv. The DPO (or their mechanic) of my Sprite used so much of it working on the engine that when I tore the engine down after oil starvation problems I found it covering the oil pick up screen in the sump and almost completely blocking the oil way from oil filter to block. Needless to say I have developed a prejudice against Blue RTV!
Thanks for the help fellas
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jv
 
Dosent this get all buggered up when bleeding? I loosen/tighten at least 10 times when bleeding.
Seems like the tape would be desintegrated by then.
Maybe I am just a bit confuse-afied.....
 
What is the point of using the tape? Bleed screws have a seat that they seal on at the end of the screw. The threads are NOT part of the active seal. The bleed screw is not tapered like pipe thread where the tape is an active seal. If the bleed screws leak (I have never seen one) then the seats must be buggered. Replace the screws and/or resurface the seats in the cylinder. If you are worried about siezing; don't over tighten the screw. They don't need to be torqued to the full capability of the wrench.
 
I would also suggest not using the tape in these circumstances. It will not help seal. Only value is to maybe and that is MAYBE prevent future freezing up but I doubt it will even help that. As said already, losening and tightening when bleeding will most likely make the tape that much more usless.
 
Anti-sieze is good stuff, EXCEPT it contains petroleum and that is NOT good for brake systems. If you were very careful with it and did not use too much, it should work fine.
 
[ QUOTE ]
What is the point of using the tape?

[/ QUOTE ]
"Some" people use vacuum bleeding from the screw end of the system. It works quite well if the screw threads are sealed so that air can't get into the vacuum. The tape also keeps the screws from rusting/corroding into the cylinder, if like some of us, you don't bleed the brakes more than once every five years. To each his own.
D
 
The plastic vacuum pumps, like the one Moss sells are great. One person bleading with no problem.
 
JV The use of RTV is oversold. I like to parallel it's usage to soldering. It will enhance a good sound mechanical joint - it will not fix it. Try soldering an oil covered pipe - no go. RTV should be used to enhance joints where the gap is over 0.003" but works better at gaps of 0.02". RTV has good elomgation properties but very low shear strength, and gaps under 0.003 put the material into shear. Gaps under 0.003" should utilize PST [ Pipe Sealant w/Teflon ]. Remember you can't be too clean only too dirty when using these materials.

Regards, Bob
 
Bob,
The auto parts store shure oversold the RTV to the DPO.
What a mess! Thanks for the info.
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jv
 
Walter,
I used a mityvac today for the first time. twenty minutes tops and i was done! Im sold! I was still pulling some bubbles through the threads even though I gave them a wrap of teflon tape. The brakes are nice and firm though. The vac worked so quick I had time to flush the clutch line of its old fluid also. Its a great little tool!
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jv
 
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