924Board.org

[Mkol]

Hi Guys - it was all going so well... been having a great time restoring the front suspension/brakes on my 1979na and then i snapped off a bleeder screw...aggg!

ive tried every trick i know, (which is quite a few by this point!) and i think its beaten me.

cant seem to find a new or used caliper for a sensible price so does anyone know of any confirmed bolt on alternatives?, Audi? VW? im sure i saw somewhere that a 80s/90s Passat would work.

[Cedric]

Can't you bore it out? Or take it to a local machine shop that can do it?
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1980 924 Turbo
www.instagram.com/garagecedric/

[Mkol]

[Mike9311]

Every trick probably included an "easy out" but in case I will ask...did you try this down the center hole of the broken off piece? They make these in a finer thread version as well. Please ignore if you know and/or already tried them


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1980 931 since 1989
1981 Ideola 931 Club Sport
1982 931 Entwicklungsfahrzeug
1979 924 NA ohne 650 mit 471
1982 931 Red Resurrection - 951 IC
1982 931 parts car / resurrection?
1980 924 NA (R&D lightweight)
1982 931 wana-be GTR race car

[Beartooth]

There's a thread somewhere hear about using a VW Passat caliper - you could try digging up a pair of those (I wouldn't do just one). If we're talking replacement, I'd think you could find an original replacement eventually. It's somewhat common to swap out the early brake setup for the later four-wheel disk setup, so there have got to be a few guys around here with a good caliper sitting on a shelf. Given the size of the bleeder and how little success I've had extracting that kind of thing, I'd probably take it to a machine shop (and you might have to shop around for one that takes that kind of small job).

The only way I would try and extractor myself on something like this is if I could heat that sucker up, and I mean red hot. If the threads are corroded, my experience is that you just can't get enough torque to break them free cold. If you break an extractor off in there, it makes it difficult to impossible to drill out. Even if they can't get the broken end out, as a last resort a machine ship could drill it out and thread and install a bigger bleeder. You could conceivably do that with a hand drill and the appropriate taps (you'd need two: a standard tap, and a bottom tap), but with a significant possibility of ruining it...
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1980 931 diamond in the rough

[Mclaren924]

[Kenodog]

I've been a machinist for ten years now and when we need to remove broken screws we :

1) Drill out as much of the screw as you can by looking up the minor diameter of the thread and drill to leave just enough that you don't bugger the threads in the part. What this does is to relieve the strength of the insert. The thicker it is the harder it is to get out. This is the most finicky and difficult part of the job. The more time you take and the better job you do if it the easier steps 2 & 3 will be. Many times, if you can drill it out so the remainder is paper thin then with a simple pick you can collapse the top part which breaks the seal of crust holding it in.

2) Heat the part gently with a torch. Not red hot but maybe 200F, *Just too hot to touch.* Then drops of penetrating oil overnight.

3) Use a LEFT HAND taper tap and start threading it into the hole of what is left of the stuck screw. Usually by about the 3rd or 4th turn the thing comes loose and you just spin it out.


This trick was shown to me by an old Czech tool and die makers and it has never failed to work. We remove little 6-48 scope ring screws even, doesn't matter the size of the part.
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1979 Euro 931, Olive
1981 931, Sabine
1991 Ford Ranger XLT 4x4, Ricky
1996 Ford E-350 ex-FedEx Van
2014 Mazda CX-5 (Kinderwagon)
2019 KTM 790 Adventure
2024 KLX300
2024 KLX140

[Mike9311]

All the above techniques work but it depends on your patience, experience, and the situation. Extractors don't work once you remove too much material but the left handed tap idea could in a thinner wall application.

If you are really good, you can remove most of the material and peal out the thread with small screwdriver and pliers. I just did this not a month ago on a 16mm thread

You just have read your situation carefully as you go.
_________________
1980 931 since 1989
1981 Ideola 931 Club Sport
1982 931 Entwicklungsfahrzeug
1979 924 NA ohne 650 mit 471
1982 931 Red Resurrection - 951 IC
1982 931 parts car / resurrection?
1980 924 NA (R&D lightweight)
1982 931 wana-be GTR race car

[Mkol]

really appreciating all the detailed replies guys thanks.

I first snapped off one EZ out and then managed to drill it out again, tried with a bigger one and then that duly snapped too, it somehow took the top 1-2mm of bleeder with it though so now its sitting a few mill below the surface with the second EZout stuck in it!

Im going to try the drilling it out method by gradually increasing the bit size until i can hopefully pry out the shell as mentioned here. as im sure youve all experienced the trouble is getting a perfectly central bore..

there is a guy on ebay here in the UK selling a VERY crusty caliper for £50 currently but for all i know the bleeder is seized in that too!

[scm924s]

Try here

https://www.autodoc.co.uk/car-parts/brake-calipers-10907/porsche/924/924-1975/2974-2-0?

Do your own checks to ensure correct part.
_________________
1984 n/a Ruby Red Metallic
1988 924S Guards red- sold
1986 924S Guards Red - sold
1984 n/a Black - sold
1980 n/a Le Mans#1 - sold
1980 n/a Le Mans#2- sold
1977 Martini - sold

[Mkol]

just to follow up on this...

SUCCESS!!!

for anyone in the same situation that finds this thread...

i managed to drill it out by gradually increasing the size of the bit and then used another EZ out to pull out the shell. the key here was that i went and bought some fresh cobalt drill bits and that made the whole thing a lot easier. I was also very careful not to drill too far and damage the seat.

I did manage to slightly mangle some of the threads but slowly screwing in a new bleeder and backing it in and out seemed to sort that out.

I know that the new bleeder is seated well enough as it sealed enough to allow me to push out a very stuck piston using a bike pump on the bleeder.