Master Cylinder Installation for Pre '71 Land Cruisers

This page is a step by step instruction based on how I replaced the original 1970 master cylinder to a late model mini truck master cylinder. 

Index

Parts List
Tools List
Instructions

Parts List

The first step is to collect all the necessary parts.  The table is a list of parts I used.  I purchased used master cylinder and booster from a junk yard and then bought a rebuilt master cylinder to replace the used one.  If I were to do this swap again I would order a late model Land Cruiser or mini truck clutch master cylinder with a lower profile.  I ended up cutting a hole in the stiffening channel on the under side of the hood to allow clearance for the relocated original clutch master cylinder. 

Tool List

You will need the following tools for the MC swap and lines.  The following table shows what tools I used.

Instructions

1. The following items will need to be removed from the firewall:
   1. Clutch master cylinder(unless you are replacing it you can just unbolt it from the pedal and firewall and set it out of the way leaving the hose on it).
   2. Clutch pedal
   3. Brake master cylinder.
2. Once the firewall is clear you will need to remove the sheet metal stiffening rib that goes between the clutch and brake master cylinders. 
   
3. The next step is to fit the master cylinder to the fire wall.  For the mini truck master cylinder the hole for the actuator rod needed to be enlarged and lowered.   Using the aluminum spacer that goes between the booster and the fire wall I fabricated a mounting plate from 1/4 steel plate.  Then the mounting plate was used to transfer the hole patterns to the fire wall.  I then welded the mounting plate to the fire wall.  To allow the bolt pattern of the master cylinder to match up with the existing pedal support structure in a way that would allow access to the nuts on the inside of the firewall I lowered the master cylinder about 3/4 of an inch.  Once the mc was mounted to the firewall I drilled a new hole in the pedal for the cross pin.   To verify that this would not compromise braking I compared the lever arm ratio this produced with my 92 toyota truck.  The lever arm ratio turned out to be almost identical with the change.  If the original hole was used the pedal would produce more force on the mc but would have had slightly less travel.
4. Once the brake mc is in place the clutch mc must be remounted.  Due to the fact that the booster is now in the way of the original mounting spot the clutch mc must be moved.  After going back and forth a couple of times I decided to fabricate a new support bracket for the pedal instead of adding a side arm to the pedal.  Using a piece of channel iron and another 1/4 inch plate I fabricated a new bracket that bolted to the inside of the fire wall.  This mounted to the outside of the existing support structure for the pedals.  Once in place I ran a small bracket from the top of the new bracket to the existing bracket to eliminate the twisting force placed on the firewall.
   
5. Once both mc's are bolted in place make sure there is no binding when they are moved through there full range of motion. 
6. To complete the setup for 4 wheel discs I used an aluminum plate to mount the proportioning valve to the mc booster.
   

Last Updated:  02/16/09
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