MR2 SpyderChat banner
Cancel
Create thread New Garage Forums

Manual Steering Rack / De-powering Steering Rack Guide

Jump to Latest
38K views 63 replies 19 participants last post by  Ohio Enthusiast  
#1 ·
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:

  1. 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.
  2. Using two large adjustable wrenches, loosen and remove the Driver's side rack end. These are normal threads but are torqued into place.
    Image
  3. 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.
    Image
  4. 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.
    Image
    Image
  5. The Pinion shaft should simple rotate out of the assembly and will look like the below image.
    Image
  6. 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.
    Image
    Image
  7. 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!
    Image
  8. 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.
    Image
    Image
  9. 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.
    Image
    Image
  10. 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
 
#2 ·
I picked up a spare rack a while ago with the intention of doing this, just haven't got around to it yet. What are your impressions of it? Just curious if it is suitable for a car that is driven real world (low speed parking lots and such) and are you running 0 degrees of toe now or even toe-out?
 
#3 ·
To be honest, I haven't gotten the opportunity to test this out on a rolling chassis. The motor is still being built and it will be early September before it touches the ground. I can comment on the "looped" system, but even then I have never driven the car with the power steering functioning.

From what I've read, my comments are very much in line with what Jack wrote way back when.
 
#5 ·
When I was younger my ford festiva didn't have power steering, the steering wheel was a tiny bit harder to turn at low speeds but I didn't mind it at all.
 
Save
Reply Quote Like Like
#15 ·
The below method is simply looping the hydraulic hoses. When I received my car the PS was already looped and it felt great. Very connected. The difference is the fact that the fluid can act as a damper, for better or worse. Also, When my PS was looped, the previous owner used a filter to allow the system to vent to the atmosphere. I hated the look of this and it allowed dirt to enter the system which could cause binding issues.

Looping the Hydraulics is a good way to test it out and see if you want to go to this extreme.



dblotii said:
I think that with this method, you still have to deal with some extra resistance due to pumping
PS fluid from either side of the rack piston when you steer.

Dave
Click to expand...
 
#17 · (Edited)
I have felt the steering without power assist but connected. Extremely heavy. If I where to so this I would loop the fittings and disconnect power to the electric pump-no need to run. The PS warning light is something else to consider and deal with. I would do this if the electric pump where to fail.
 
#23 ·
OldMan said:
It's refreshing to see this discussion revived.

Sooner or Later, EHPS fluid will become unavailable.
Sooner or Later, the Power Steering will fail.
In this eventuality, what shall we do?

We must either find an alternative to EHPS fluid or forgo power steering.
I never understood why the Spyder had PowerSteering in the first place.



BTW -------------------
I brought this topic up some time ago, but nobody cared.
Times change, and those 'ahead of the curve' must wait.
Click to expand...
PS advantages are better because you can quickly toss the car around and can take advantage of a shorter ratio. The manual rack gives you better road feel but it also dulls the nimbleness of the car.
Formula one cars use PS and if it didn't have enough of an advantage they wouldn't use it.

Bottom line is, it's a mixed bag but for me I like the manual feel because it give you a go-cart like sensation.
 
#25 ·
OldMan said:
Dev:
It's good to see you back on SpyderChat.
Click to expand...

At the moment I'm deeply into one of my effeminate hobbies of trying to pull the perfect espresso shot. It's a very complex subject dealing with various brew temps and pressures but I'm on the verge of mastering it to my satisfaction. Then I will get bored again and will get back to my manly hobbies. Tired of debating women on coffee forms.

I almost have enough energy to get my car fixed up and ready to drive after three years.
 
#27 ·
OldMan said:
I think I understand your meaning:
Disregard the coffee: Starbucks has already established that a cup of coffee should cost about $50.
The Moose Menace in Canada is well known. The Elk population in Siberia and the reindeer problem in Lapland are under control.

All that aside. I'm glad to see you posting on SpyderChat again.
Click to expand...
Actually I got into the coffee hobby three months back from the guy that sold me his 2zz years ago. Basically showed me how bad Starbucks actually is to the point where I no longer crave it. I don't plan to compete in the Barista world championship anytime soon but it's good not to be ignorance about wasting money on $5 coffees.
 
#29 ·
I deleted the power steering and looped the lines. The steering is unacceptably heavy in a racing environment. It's acceptable while putting around the pits and access roads.

In summary: I regret pulling the power steering with all my heart and I want it back again. I'm in market for buying one. :)
 
#30 ·
Man, If it weren't for the fact that it would bump me up to too high of an AutoX class, I would sell you my PS stuff in a heartbeat. I haven't driven it with the PS off yet, but just sitting still with the engine off, the wheels turn easier than my last car (non PS from factory) did.
 
M
#41 ·
"powered" accessories

My first MR2 was a 1986. I believe it had manual steering, brakes and windows. Loved it. As the car evolved and got heavier I understand the PS and PB - but why for the Spyder at barely over 2200 lbs?Power Windows I like - guess I'm lazy. Sometimes I feel like the Power Steering is a tad quick for its' (or mine) own good. Maybe I'm still "learning" the car - it's only been 6 months!
 
S
#42 ·
Yea, I am not a fan of it. When I first got my car running with the 2gr it did not have the pump working and I really did not miss it. I eventually "fixed" it. And I actually want to ditch it now. The car actually feels more dangerous to me with it. I like to have some resistance and feedback in the steering. Especially with how powerful the engine is, a jolt of acceleration can easily cause me to turn the wheel more than I need to.

MRSPONZ said:
My first MR2 was a 1986. I believe it had manual steering, brakes and windows. Loved it. As the car evolved and got heavier I understand the PS and PB - but why for the Spyder at barely over 2200 lbs?Power Windows I like - guess I'm lazy. Sometimes I feel like the Power Steering is a tad quick for its' (or mine) own good. Maybe I'm still "learning" the car - it's only been 6 months!
Click to expand...
 
D
#45 ·
I am going ahead and getting my pinion welded because I was dis appointed in the improvement in steering feel from my depowered rack. The Miata community reports that this makes a big difference. I will report my subjective results.
Dave
 
#48 ·
83914


I got it depowered, but I get some rattles when i go over small bumps (but not big bumps). I think it is because the passenger side of the rack is no longer being held as securely as before. There is some space between the 2 pieces of metal in the 2 arrows in the picture, and it isnt flush. Did anyone else experience this? probably not a problem other than the annoying rattles
 
D
#49 ·
amefuto said:
I got it depowered, but I get some rattles when i go over small bumps (but not big bumps). I think it is because the passenger side of the rack is no longer being held as securely as before. There is some space between the 2 pieces of metal in the 2 arrows in the picture, and it isnt flush. Did anyone else experience this? probably not a problem other than the annoying rattles
Click to expand...
I do not have any rattles. My guess is that you have set the pinion pre-load too-low. Try a small adjustment, say 1/4 turn in.

Dave
 
D
#54 ·
I actually do not recognize where that part goes. Does the rack run through this? I know that I did not have anything like this left over after my rack rebuild. I suggest you review the de-powering article in-detail. It is correct, except they left out welding up the valve to make it torsionally solid.

Dave
 
#55 ·
the rack goes thru this. This part seals the oil on the passenger end side. it slides around on the rack but its a tight flush fit. only rubber comes in contact with the metal of the housing and rack. See pic below.

Im gonna guess putting this in will help the rattles. it's not too hard to do, since I think i can push it in thru the passenger side by just removing the tie rod. I'll try that.

i did go over it and detail and i still dont know. thats why im asking lol. ty anyways!!
Image
 
MR2 SpyderChat
posts
1.2M
members
30K
Since
2003
SpyderChat Forum is a community for Toyota MR2 Spyder Enthusiasts to discuss specs, reliability and more!
Full Forum Listing
Explore Our Forums
Performance Modifications Care, Maintenance, and Troubleshooting MR2 Spyder Main Forum Appearance Modifications Parts and Miscellaneous for Sale