Date: 3 Jun 1997 09:21:19 -0600
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: "Carl Hansen" <Carl_Hansen@ATK.COM>
Subject: re- break job/busted bleade
BatSubject: re: break job/busted bleaders 6/3/97 9:57 AM
ON - Mon, 02 Jun 1997
Jim Maginel <c455ssl@semovm.semo.edu> - SAID
To: vanagon@lenti
Subject: Break job
I have been experiencing low pedal pressure, and decided to adjust the rear
drums and then bleed them. The rears bled well enought--black fluid
suggested they needed it, but when I moved to the front, the bleeders were
rusted stuck. I broke one off trying to free it, and was surprised to not
have the fluid run out.
Now what do I do? Is there a procedure for replacing a broken bleeder
screw? Is is safe to drive as is?
Unfortunately, the low pedal pressure remains...
TIA for any sage advice,
Jim
85 Midwesty
*********************************
Ditto, Been there, Done that. Luckily I have access to a full machine shop
and was able to do something about it. My machine shop consists of a vise and
a Makita 9.6 volt drill. (Well, OK, I do have access to a machine shop as
well, but I started at home. Doing this at a machne shop would be the best
way to go. I might not have had to recess the hole so much to allow the new
bleader valve to sit in deeper if I had done this in a proper drill press or
mill set up to start with.)
HOW TO:
o Take the caliper off. Carefully drill out the busted break bleader.
Make sure you drill straight into the hole, and go slow. The bleader is REAL
soft and will cut easily You are drilling the unit with the hole
horozontal, or even pointed down a bit, right. You don't want to get too many
chips into the mechanism.
o DO NOT DRILL TOO DEEP. YOU DON'T WANT TO DAMAGE THE SEAT THAT THE BLEADER
SEALS AGAINST. DO USE A DRILL SMALLER THAN YOU THINK IS CORRECT. IT'S NOT
NICE TO CUT INTO THE THREADS OF THE CAST IRON CALIPER.
o Carefully pick out what remains of the old bleader. the pieces should fall
away from the tapped hole. You might have to PURSUADE them a little with a
sharp, narrow awl or point of some sort.
o Carefully retap the hole with the correct tap. You'll know which is the
correct tap, cause you went to the dealer to get a new bleader fitting.
REASEMBLE: Carefully. Make sure you got the hole cleaned out well, and away
you go.
It's really nice when you have access to a real machine shop. I do, and they
fixed up the seat for me, and recessed the area around the hole to allow the
new bleader valve to sit a bit deeper in.
Now here's what can go wrong:
o You drilled too deep. OOPS, you shouldn't have done that. But now you
need to find a drill bit or cutting tool or grinder bit with the correct flare
on the end to rebuild the seat. I forget if I used a drill bit or found a
bit, but I did get the seat rebuilt.
o Since the seat is now deeper than before, you will probably have to recess
the area around the hole to allow the new bleader to sit deeper into the
caliper. I had to recess it about 1/16 inch.
o You got chips in the hole. DON"T DO THAT. Really, I didn't, or I don't
think I did. If you do, pick them out, don't blow them further in. Or maybe
try to flush them out with old brake fluid forced in from the other side.
Ch
'89 Syncro "Beast"
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