This document was created and written to aid users in converting the OEM Toyota MR2 Spyder steering rack into a Fully Manual, Depowered steering rack. I do not assume any responsibility of any damages which might occur during the installation or use of this conversion.
Caution: Protective eye wear and gloves are recommended. Hydraulic fluid is known to irritate skin and during this conversion you might need the use of power tools.
Handy tools you will need:
3/8” Drive Ratchet and extension
17mm, 14mm, 12mm, 10mm, 9mm, 8mm sockets
15/16” Wrench or socket
19mm Allen Wrench or socket
Flathead and Phillips screwdrivers
Hammer and Chisel
Cutting Wheel
Magnetic tool retriever
This write-up assumes that the user is able to remove the steering rack from the vehicle. In order to do this you will need to perform the following operations per the BGB
1. Place Front Wheels Facing Straight Ahead
2. Remove Steering Wheel Pad
3. Remove Steering Wheel
4. Remove Luggage Compartment Trim Box Cover
5. Remove Tool Box
6. Disconnect pressure feed tube and return hose from power steering vane pump
7. Remove front luggage under cover
8. Disconnect RH and LH Tie Rod Ends
9. Remove PS rack assembly (2 bolts, 2 nuts, 4 plate washers and PS rack assembly)
Now to begin the process of the conversion:
Caution: Protective eye wear and gloves are recommended. Hydraulic fluid is known to irritate skin and during this conversion you might need the use of power tools.
Handy tools you will need:
3/8” Drive Ratchet and extension
17mm, 14mm, 12mm, 10mm, 9mm, 8mm sockets
15/16” Wrench or socket
19mm Allen Wrench or socket
Flathead and Phillips screwdrivers
Hammer and Chisel
Cutting Wheel
Magnetic tool retriever
This write-up assumes that the user is able to remove the steering rack from the vehicle. In order to do this you will need to perform the following operations per the BGB
1. Place Front Wheels Facing Straight Ahead
2. Remove Steering Wheel Pad
3. Remove Steering Wheel
4. Remove Luggage Compartment Trim Box Cover
5. Remove Tool Box
6. Disconnect pressure feed tube and return hose from power steering vane pump
7. Remove front luggage under cover
8. Disconnect RH and LH Tie Rod Ends
9. Remove PS rack assembly (2 bolts, 2 nuts, 4 plate washers and PS rack assembly)
Now to begin the process of the conversion:
- Using a Flathead Screwdriver you will need to remove the clamps holding the RH and LH dust boots to gain access to the rack ends.
- Using two large adjustable wrenches, loosen and remove the Driver's side rack end. These are normal threads but are torqued into place.
- Remove the adjusting cover by first removing the large lock nut. The cover is a 19mm hex and is fairly easy to remove (not highly torqued). Then using the magnetic tool you'll need to remove the spring and support yoke. The parts are laid out top to bottom in order of their removal below.
- To remove the pinion shaft you will first need to remove the pinion shaft housing which is retained by to 12mm hex screws. Be sure to keep the gasket in a safe place as this will be reinstalled later in this procedure. You will also need to remove the pinion shaft retaining nut. This is done by first removing the cover using a 15/16" hex socket and then the 17mm nut.
- The Pinion shaft should simple rotate out of the assembly and will look like the below image.
- The steering rack is held in the housing by a stop ring and is located at the opposite end to the pinion shaft. Using two flat head screw drivers you should be able to pry out the stop ring. Keep this stop ring as it will need to be reinstalled into the housing.
- With the steering rack free of its housing, you will now need to remove the seal. To do so you can simply remove the retaining clip. I was unable to get this clip out so I simply cut the seal and seal groove from the shaft. BE CAREFUL NOT TO DAMAGE THE STEERING RACK ITSELF!
- With the internal seal removed, we do not need the lines any more. You can source plugs for these holes or you can simply cut the tube and crimp them shut. They are no longer holding pressure, but are needed to keep dirt and debris out of the system. Alternatively you can weld the plugs shut.
- Before reinserting the steering rack and pinion, be sure it's well greased. Once it's reinserted into the housing you will need to reinstall the stop ring from step six. The assembly of the components is simply the reverse of the afore mentioned steps.
- The torque specifications for the parts are listed below.
- Rack End (step 2) - 62 N-m or 46 ft-lbf, ensure weep hole is not blocked
- 19mm Allen (step 3) - 25 N-m or 18 ft-lbf, adjust (outward) so turning preload is 6.7 - 11.3 in-lbf
- Lock Nut (step 3) - 28 N-m or 21 ft-lbf, with loctite (be careful not to further adjust the 19mm Allen)
- 12mm Hex (step 4) - 21 N-m or 15 ft-lbf
- 17mm Pinion Nut (step 4) - 24.5 N-m or 18 ft-lbf
- 15/16 cover (step 4) - 59 N-m or 43 ft-lbf