Pirate 4x4 banner

1 - 12 of 12 Posts

·
Registered
Joined
·
1,375 Posts
Discussion Starter #1
I recently completed 4wheel disc brakes, toyota large vented front with MCarlo rear.

I kept the original 72 booster, but upgraded to a 4wheel disc brake Master (15/16th bore) that came from a supra.
The problem I was experiencing was that after a mile of driving, the brakes would begin to progressively apply pressure to the rotors (all rotors).
The first time I was able to make it back to the shop...not so lucky the second time (yesterday), I had to call a tow truck for assistance.

Initially I was running 2lb residual pressure valves, which have been removed...no difference. After calling the Profitt's, I was told to address some attention to the booster.

I found that the booster was prematurely applying a slight amount of pressure to the MC. I cranked it back all the way, and my dragging calipers from HELL are no longer.

With I could have figured it out before the Costal...next time.

40 stops sweet :smokin:
manny

sorry, no pics :D
 

·
Registered
Joined
·
359 Posts
Hello Manny

Manny, I was going to post a question about master cyliners but I think maybe you answered it all ready. But what year supra master cyliner? My 4 wheel disk brakes work like crap, need help thanks. :(
 

·
Registered
Joined
·
1,375 Posts
Discussion Starter #3
Dale,
Two things to look for:
The MC needs to have a bore/cylinder size of AT LEAST 15/16 , due to the volume requirements this is mandatory (look on the passenger side of the MC for the casting indicator).

Try and get one from a 4wheel disc brake car, as this will insure that there is no residual pressure designed for drum brakes in the MC.

I have read here on Pirates that some MC's have residual valves which are removable...mine did not. The later FJ80 MC's have a 1" bore, but you don't find too many of those...

I was discussing my initial issue w/Toploader yesterday, and he told me a little trick:

Push the Booster Rod into the Booster (towards the fire wall), now pull it out about a 1/4 inch.
Place your MC flush w/the booster...I don't think It's necessary to install, as long as it is tightly placed against the booster. Now remove the MC so you have access to the BR.

Using your fingers, carefully push the BR back into the Booster. If It does NOT move...you
don't have any clearance and need to Adjust the Booster Rod (requires two 8mm wrenches to adjust). I would say 1/8 clearance would be enough, but YMMV.

Remember, your Pedal also has an adjustment, I believe the toyota manual indicates 1/2" clearance...before it in-gages the brakes.

I am not running a proportioning valve, and my cruiser brakes stops on a dime....go ahead, pull in front of me :D

Let me know If you have any other Q's,
manny
 

·
Registered
Joined
·
613 Posts
manny

manny
you sure have been getting it awnnnnnnnnnnnnn!! with your cruiser !!!
can I run with you on the rubithon ???
I"m proud of you !!you rouckie ?? rukie ? rockie ????//
 

·
Registered
Joined
·
1,375 Posts
Discussion Starter #6
Uncle Mike,
thanks, I bet you had quite the cruiser pase a few years ago with your 55 :D

you are always welcome...I am planning on driving up Wednesday night and hooking up w/Georg's run as they go through the slabs Thursday morning.


Dale,
Let me know If you have any other Q's...

See you both at Terri's KC this year?

manny
 

·
Registered
Joined
·
771 Posts
Do you have a part # for that MC or did you yank it from a wrecked car? I am just starting my conversion today---mini truck front(non vented)& TSM kit in the rear.
 

·
Registered
Joined
·
1,375 Posts
Discussion Starter #11
KT40 said:
Do you have a part # for that MC or did you yank it from a wrecked car? I am just starting my conversion today---mini truck front(non vented)& TSM kit in the rear.
I prefer the term donor vehicle :D

Toyota cressida or supra w/4wheel disc brakes and "15/16" in the casting on the passenger side of MC...
 

·
Registered
Joined
·
771 Posts
Thanks-I"ll start looking for my "donor". :)
 
1 - 12 of 12 Posts
Top