Stripped brake bleeder screw

[oscaac]

Hi All,

I was doing a brake flush on my 2005 Carrera 997.1 and got through 3 of the 4 brake lines flushed. When I got to the front left side which is the last in the order, the bleeder screw on the caliper is stripped. The 11mm wrench just moves freely on it. Anyone deal with a stripped bleeder screw before? What are my options? Do I just need to take it to the shop? Any advice is appreciated. Thanks in advance.

[Hilux2400]

You need to find out where it has stripped or if it has broken. I assume the top bit with the hexagon is turning, so try pulling and turning to try and extract it.  I assume that if it's not leaking fluid the bottom tapered part is stuck in and the top half has severed, this might mean that you have sufficient thread to get a new nipple screw to bite. 

 

I have had a similar experience with a different make of car resulting in an over tightened bleed screw.  In my case the hexagonal head just broke off.  

 

You might be able to get the bottom bit out by using a reverse tap extractor. You feed this into the hole in the nipple and unscrew it.  As the remaining bit screws out, if you are lucky, it will recut a thread in the calliper. However, beware not to apply too much torque to the screw extractor as if it breaks off in the hole you will be really messed up an have to buy a new calliper ( I have had this experience).

 

I think you can send your calliper off for repairs of this type which involves drilling out the bleed nipple and tapping a new thread and taper seat.     

 

Since my experience with a cracked bleed nipple I now apply anti-seize to the top part of the thread before screwing home.  Also, when unscrewing for the first time I always apply penetrating oil to the nipple and jolt the ring spanner with a rubber hammer, rather than applying pressure from the start.   I find the jolt will normally crack it open for bleeding.  I also use a vacuum bleeder as it avoids having to press the pedal to the floor through an abnormal travel distance where the M/C seals might get damaged on an unpolished surface. 

[oscaac]

Thanks Hilux2400. The hexagon is just turning so I believe it's just stripped. It's not leaking or anything so the brakes are still good. Good advice on the penetrating oil and rubber hammer; I'll start doing that as well.

I was thinking of seeing if I can take it out with a damaged nut remover. You think that will work? Is it possible to replace the bleeder screw without removing the caliper? Is there a special process for doing so?

[Hilux2400]

I have no experience of caliper overhaul and re-making the threads.  I have only heard about it done by specialists. Maybe someone will be along to give advice on this.  However, if it is re-tapped you would need to get the muck out by blowing through and for that I think the pistons would have to come out and the caliper removed.

 

It sounds to me as if the bleed nipple has broken in half.  What you are turning is just the top half attached to the hexagon.  The bottom with the taper is still in the hole. 

 

Good luck with it.

[Mijostyn]

Hi oscaac. 

 

You can do this with the caliper in place. Take the broke off part to the hardware store and get an Easy Out that the tip just fits in the center hole. You might also want to get a tap that matches the thread in the bleeder hole to freshen the threads once you have the remainder of the valve removed. Spray some WD40 into the hole then gently tap the easy out in and back out the remaining valve. You should bleed the caliper copiously after to flush any debris out using a pressure bleeder which you can get from Pelican parts. On the first bleed I remove the valves and spray them with a product called CorrosionX. This is a very high sulfer very heavy oil. Amazing stuff. I coat all my tools with it and they never rust.

[oscaac]

Thanks Mijostyn. However, the upper part of the bleeder screw is not broken off completely...yet. The top part is just rounded off so my 11 mm wrench doesn't catch it. I was thinking of using a damaged nut remover to try to take it off and replace it. If that doesn't work and breaks the top part off, then I'll use your advice with the Easy Out. Thanks for the tip on the CorrosionX. I'll start doing that too to prevent this from happening again. 

[j_beede]

In that case all you need is a 6" pipe wrench or vise grips (and a new bleeder screw) -- assuming there is adequate room for the wrench or pliers to access the screw.