Brake Fluid + Thread Compound or Tape = What?? (1 Viewer)

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I replaced my slave cylinder and it leaked at the fitting. So I replace the fitting, still leaks. The fitting is bottomed out like it is suppose to be. I fear that if I tighten the threads any more that it will strip the threads. Can I use teflon tape or some kind of thread compound that will hold up?
 
No tape! What kind of flare is on the brake line? It needs to be a double flare. (Search for double flare to see what I mean.)

The fitting that goes into this slave cylinder is a bubble fitting, which I believe mates up to the slave cylinder correctly. See my sig line, this is a GM slave cylinder. I don't know my brake line terminology but at the parts counter they refered to it as a bubble fitting. I did a search for double flare and it doesn't look like that.
 
I replaced my slave cylinder and it leaked at the fitting. So I replace the fitting, still leaks. The fitting is bottomed out like it is suppose to be. I fear that if I tighten the threads any more that it will strip the threads. Can I use teflon tape or some kind of thread compound that will hold up?
Teflon will only seal the threads and the tubing itself.
You should be able to tighten it engough to stop it leaking or you have a problem with the flare or the flare seat.
You should be able to fix either. I would reflare the line first. If you post pics or more info about the cyl ,you will get better help.
I bought fitting just the other day and they sold me a buble flare connector when I needed a double flare.You should be able to till the diff, one is conave and the other is convex.
 
Is the brake fitting bottoming out on the flare end? Or is it the "nut" side of it that is bottoming out?

The fitting is definately bottoming out like it is suppose to. there is even a thread or 2 left over.
 
Teflon will only seal the threads and the tubing itself.
You should be able to tighten it engough to stop it leaking or you have a problem with the flare or the flare seat.
You should be able to fix either. I would reflare the line first. If you post pics or more info about the cyl ,you will get better help.
I bought fitting just the other day and they sold me a buble flare connector when I needed a double flare.You should be able to till the diff, one is conave and the other is convex.

What I had before is "exactly" what I just put on new, the new slave cylinder and the fitting are the same as the old. It is definately not a flare. I will try to post a couple pics. When it comes to my words, a pic is worth a couple thousand!!;)
 
The bubble flare is used with a male swivel nut, and seals at the bottom of a drilled and tapped hole, with a nice angled bottom. While it can usually be resealed, it has a limited lifetime - there's no good way to get back the deformation that was crushed out for the first seal, short of remaking the flare from scratch.

That is a quote from this site: Brake Plumbing Secrets Revealed! Pics would help for sure ;)
 
Teflon tape and thread sealing compounds only work on tapered pipe threads.

Brake lines seal on the flange. If the flange surfaces are damaged or dirty they won't seal. If cleaning them doesn't fix the problem, either the flange or seat is bad and needs to be renewed.
 
OK, so here is what I have. The old slave cylinder leaked so when I replaced it the new fitting leaked (old fitting didn't leak).

New fitting on the left and old on the right and the hose above.
Lydia Track-Slave Cylinder 004.jpg

The old slave cylinder.
Lydia Track-Slave Cylinder 005.jpg

The new slave cylinder.
Lydia Track-Slave Cylinder 006.jpg
Lydia Track-Slave Cylinder 004.jpg
Lydia Track-Slave Cylinder 005.jpg
Lydia Track-Slave Cylinder 006.jpg
 
Any thoughts on why these 2 new parts would leak when two old parts didn't leak?
It is good and tight and bottomed out.
 
I am no expert,
It seems like a toyota flex hose with an adapter to hook to that slave cyl.
I would replace with the proper hose (if that is waht normally goes there) that will bolt to that slave cyl then use the porper fitting and reflare the line coming from the clutch M cyl or change it alltogether.
Easy to change the flare and fitting and the even the size of the tube.
 
The plug gizmos seal on the tapered surface, so if both the new and old one don't seal, chances are that the tapered seat in the casting is bad.
 
It it leaking from the hose threads? Replace the copper washer.

If leaking from the adapter threads could it be the adapter is made from soft brass (it looks like brass in the photo) and your never getting a good seal? I don't think I have ever seen brass used in brake systems before...
 
If leaking from the adapter threads could it be the adapter is made from soft brass (it looks like brass in the photo) and your never getting a good seal? I don't think I have ever seen brass used in brake systems before...

I have not seen Toyota use the brass seal but I know GM uses them. I have the brass brake line seal on my rear disc brake conversion. It came as part of the banjo fittings.

Tom, since you have the cyliner out, ball up a little emory cloth and lightly clean up the seat of the fitting and the fitting. Be sure to flush everyting well before you put it back into service.
 
I will try cleaning the old fitting and try it with the new slave. I tried this once but didn't clean the old fitting.
If this doesn't work I will proceed with banging my head against the wall and cursing (although this process has not helped in the past).
 

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