V1 Bleeder valve leaking

[ToxicBill]

It would seem that the bleeder valves on my brakes are leaking from around the threads. Any thoughts as to why this might be happening? An I supposed to put and sealant around them? I've tightened then does as much s I'm comfortable doing so for dead they will snap or strip.

 

[George]

Remove and inspect bleeder tip.
Remove caliper shape a wooden dowel for the hole to match tip of bleeder use lapping compound and polish the seat in the caliper then clean.

Brad

 

[ctuinstra]

Brad's is the best answer but you could also try to loosen then and retighten about 5-10 times. This may help them mate better.

 

[Rttoys]

Yep. The 2 mating surfaces have to be clean and smooth. No sealer required.

 

[Waterdriver]

What are using to tighten it with?

 

[ToxicBill]

Remove and inspect bleeder tip.
Remove caliper shape a wooden dowel for the hole to match tip of bleeder use lapping compound and polish the seat in the caliper then clean.

Brad

Thanks for the feedback George. Can you help me understand a bit more on how to do this? Maybe I'm over thinking it but I'm wondering how I get my wooden dowel to match the shape of the bleeder.

After that, I assume I use the dowel and the lapping compound in the bleeder valve hole to smooth that inside surface.

 

[ToxicBill]

For extra context, here is what the bleeder screw seat and bleeder screw look like.

 

[George]

Use a round piece of wood dowel from the hardware store the will fit the threaded hole the shape the end on a ginder to match the taper and end of the bleed valve. use some valve lapping compound on the tapered end pushing in as you rotate the dowel, you could even use a drill motor and go both directions. Or you could get a new bleeded, remove the threads from the old one and use it for lapping.
Brad

 

[CaptFrank2001]

Take it out and swap it to the other side of the car. If the leak moves it is the bleeder valve (case closed). If not it's the probably the seat.

 

[ToxicBill]

Got it. Thanks @George

Also - I did find another thread talking about this - https://www.dfkitcar.com/forum/index.php?threads/bleeder-screws.723/

I'm gonna give the polishing a try first.

 

[ToxicBill]

Take it out and swap it to the other side of the car. If the leak moves it is the bleeder valve (case closed). If not it's the probably the seat.

Oddly enough, both front bleeders leak

 

[CaptFrank2001]

My front & rear bleeders are slightly different. I don't know if it makes a difference & if so you may have them swapped (Front to Rear). Externally they are different and one is longer. The seats MAY be different too (don't know).

 

[ToxicBill]

Ok, I've done the polishing on the bleeder screw seat and I've had the system under pressure (~10psi) and no leaks! We'll see what happens when I get it on the road, but it's way better than what it was.

Here is what I did:
- get a 5/16" wooden dowel and put a 90 degree point on it. I used a drill and 150 grit sandpaper.
- remove, drain, and disassemble the brake caliper
- using a drill and the wooden dowel, apply a bit of valve grinding (or lapping) compound to the tip of the wooden dowel, insert it into the bleeder screw hole, and run the drill for 5-10 seconds
- repeat until satisfied
- using high grit sandpaper (I used 2000 grit wet sandpaper), polish the tip of the bleeder screw. The bleeder screw fits nicely into a drill as well.
- clean everything THOROUGHLY. You don't want to leave any grit in the threads or in the piston chamber.

Resemble everything and test. How do you know when you are done? I'm not sure other than your bleeder screw no longer leaks.

 

[ToxicBill]

Also, thanks @George for the guidance.

 

[George]

My father taught me that over 50 years ago.
Brad