rear disc problem

[secretagent]

I just completed a rear disc conversion on my 75 fj40, I used a 92 4 runner master cyl. The problem I'm having is that the rotors turned freely when I first installed them, after applying the brakes the first time the rotors do not turn as easy. The pads stay semi engaged against the rotor. I'm thinking that there is some kind of valve that keeps some pressure on the rears but I don't know where it would be at on this master cyl. Has anyboy else run into this problem? If I install an ajustable prop. valve will it stop it? Any help would be great, Thanks.

 

[Poser]

Remove the rear brake line where it attaches to the master, remove the fitting that is installed in the master that the rear brake line attaches to, remove the plastic cap under this fitting, and re-install this piece that the brake line attaches to. This is a residual pressure valve that is needed for drum brakes, but not for a disc conversion in a Land Crusier.


Klear as mudd?


Good luck!


-Steve

 

[Poser]

http://www.ih8mud.com/tech/residvalve.php

 

[Bret]

I don't know for sure if it is required or not, but after removal of the valve in the master cylinder (stock 76 FJ-40 MC) I put a 2lb residual valve in line with the rear disks to keep the pads close to the rotor. It was a WIL-260-3278 from Summit Racing ($21). Never had a problem.

 

[lone gunman]

was the master from the 92 4runner for a 4 wheel disc set up? other wise you will have to do what Poser said. i used the one that www.jtoutfitters.com sells for this conversion (92 4runner with 4/w disc i believe) and it works perfectly, i have never had a problem and its been about 2 years now since the install. i did not use a proportioning valve either. also there is on my 76 below the original M/C what looks like maybe a valve body, that the short lines from the original master went through and then to the brakes, i removed this because i was told i no longer needed it. i dont remember what it was for, after all it was 2 years ago. its a DD rig and the brakes work awsome! i could send ya a pic if needed just PM me with a e-mail address. GOOD LUCK!!

 

[Poser]

also there is on my 76 below the original M/C what looks like maybe a valve body

This is a non-adjustable proportioning valve, from what I have been told..

no need for it w/ rear disc...


Good luck!


-Steve