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75 Posts
Discussion Starter · #1 ·
I installed 4-whl discs on a friends '66 FJ-45 a month ago.He has put about 75 to a 100 miles on it since, with no problems until now.
He was running down I-5 Sat. and hit the brakes, and the rear disc calipers locked up solid on him. <IMG SRC="smilies/eek.gif" border="0">
He was doing 75 or so,and skidded to a stop with smoke pouring out the rear brakes. NOT GOOD <IMG SRC="smilies/frown.gif" border="0">
Some background:
Here's the setup I installed
Toy mini knuckle-out front discs
TSM kit rear
Wilwood prop. valve(on rears)
'82 4-whl disc Supra 15/16" Master
'85 Toy mini booster
Wardens booster adapter and pushrod ext.
SSBC braided SS rear lines
Step 1
I thought the pushrod might be too long,so I shortened it up.
Took a test drive,and after about 30 hard stops,I was able to make the rears seize up again.They locked up tight on the rotors and would not release until I bled off pressure at the bleeder valve on one cal.Both rear calipers released then.
Step 2
I thought I might have gotten a bad or incorrect residual valve in the rear section of the master, so I replaced the valve with one that I had punched out (no residual pressure in the lines now)
Took it out today and the bitch locked up after about 30 stops again <IMG SRC="smilies/crybaby2.gif" border="0">
Step 3
I ordered a new (reman)master cyl. today and will try it tomorrow.

Can anybody think of anything I might have overlooked????
Just the rears are locking up
Prop. valve is adjusted correctly.
The brakes work great until the F-up,good pedal feel etc.

They seem to want to seize up on a "Panic stop"
When they seize,I still have a normal,firm pedal.
Could I have incorrectly adjusted the pushrod???
I adjusted it by "Feel" I reached up under the dash and jiggled it to mahe sure it was not engaging the piston.
Is there a better way? <IMG SRC="smilies/confused.gif" border="0"> <IMG SRC="smilies/confused.gif" border="0">

Thanks for the help.

[ 08-14-2001: Message edited by: Kaiser Bill ]

75 Posts
Discussion Starter · #3 ·
Hi Shawn <IMG SRC="smilies/biggrin.gif" border="0">
Rimrock was good.One roll over,two snapped drivelines,one flat,lots of dents,and a few almost-engine fires.Just a normal day wheelin!!!

I don't have a linelock installed.
the calipers are Re-mans but I'm pretty sure they are good.
the rotor is the correct one for the kit.
It's off a '91 1/2 ton chev.
I've been trying to get a hold of Skip at TSM, but they're on vacation.

Those are all good things to check out.
Thanks! <IMG SRC="smilies/beer.gif" border="0"> <IMG SRC="smilies/beer.gif" border="0">

75 Posts
Discussion Starter · #5 ·
Are you saying that since my Front/Rear Bias is off,thats why the rears are locking first?
I should say "seizing" I guess.
I can get all 4 whls to skid on pavement,but the rears do lock first on gravel or dirt.

I'll try backing off on the pushrod somemore,but I already have an airgap with the pedal released,should'nt this be enough? <IMG SRC="smilies/confused.gif" border="0">

75 Posts
Discussion Starter · #7 ·
Thanks for the reply, that is some good info and was well thought out.I didn't think about the other adjustment on the inner pushrod.

I think I found the problem.BAD WILWOOD PROP VALVE <IMG SRC="smilies/eek.gif" border="0">
I decided to see if I could isolate the pressure buildup,so I went out on a test drive and got the rears to seize up again.

Instead of releasing the pressure at the rear calipers,this time I tried at the master.
No pressure and the rears didn't unlock.That meant the master was working right.
Next I tried at the outlet side of the prop. valve and, presto they released.
Thats the only prop valve on the rig,being a '66, it was like yours and didn't come with another stock one.
I called Skip at TSM and he told me that he has seen 4 or 5 of these Wilwood valves go bad in the past.
Wilwood won't admit to a problem but I guess they don't want to be subject to any liability.
I'll get a new one in a few days and hopefully it will solve the problem.
Thanks for the help. <IMG SRC="smilies/beer.gif" border="0"> <IMG SRC="smilies/blender.gif" border="0">
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