40-series Power Steering Gearbox SST's & Rebuild (1 Viewer)

[SuperDuperCruizer]

UPDATE 10/2020: Attached pdf file OEM power steering write-up: Toyota Trails (March/April 1998) pages 40-44

UPDATE 05/2017: This remains a work in progress. As I complete steps, I'll add photos to help clarify details that may be unclear or omitted from the FSM.

40-series Power Steering Gearbox Housing
Used Toyota Power Steering Gearbox Toolkit ($15 + shipping Thanks, Ebay)
Used Mini Truck Power Steering Gearbox ($75 shipped Thanks fellow ih8mudder)

I've painted the housing with epoxy black chassis paint. I left some surfaces as bare metal where parts mated with another surface. Today, I disassembled the mini truck box & kept all of the parts I need for the rebuild. My first question is:

Can I clean the guts with a solvent of some sort? I'll post up some picts once I'm ready to assemble everything.

 

[HawkDriver]

Can I clean the guts with a solvent of some sort?

That's what it's made for, use it up.

Good start for a rebuild thread... but so far TTIWWOP, keep it up.

 

[SuperDuperCruizer]

GASKET KIT
04445-35040

SEAL WASHER (Included in the GASKET KIT; however, in case you'd like to purchase it separately)
90210-10001

Exploded View Diagram

 

[SuperDuperCruizer]

TOYOTA
00002-00800
1977-1/2 POWER STEERING GEAR HOUSING OVERHAUL TOOL SET

PACKING SLIP

The lock nut and adjusting plug were very stubborn to remove. You can make your own SST's but even with them it wasn't easy. Here's a picture of the corresponding OTC tools used. Pictured on the left is the Locknut Wrench [00002-00803] and on the right is the Adjusting Plug [00002-00804].

 

[SuperDuperCruizer]

New Power Steering Gearbox Housing painted as described above. The valve body was the only part saved from the first pickup power steering gearbox. I cleaned and painted the valve body as I did the gearbox housing I'm using for the rebuild. I found another used pickup power steering gearbox I'll be using for the remainder of this project.

 

[tlc4x]

Please keep going. I have one sitting in a box right now that I will soon rebuild. What pump are you going to use? Toyota or Saginaw? Do you plan on putting a radiator on the low pressure side to cool the fluid?

 

[SuperDuperCruizer]

Cleaning Mini Gearbox Guts...

Soaked the parts in solvent. Today, I'm cleaning the parts to be painted with some phosphoric acid. You can buy this stuff from any home improvement place. The brand I purchased was Klean-Strip and the stuff is called Prep n Etch. It removes the rust and provides a good surface for the paint to bond to. I'll post pictures up once I've completed the stripping process.

 

[SuperDuperCruizer]

tlc4x, I'm going to use a toyota power steering pump. I have a 40-series pump from a 1979 vintage FJ40. I will not be using the brackets since this is for the 3B I'll be using... I have most of the 3B brackets. I'm not sure if they are interchangeable, but we'll find out soon enough. Anyone interested in the 2F bracket? I'll sell it for $25.00 plus shipping.

 

[tlc4x]

I might be interested in that bracket. I haven't decided on saginaw or toyota pump yet though.

 

[SuperDuperCruizer]

I've had a chance to clean & examine the cross shaft from the used mini truck gearbox. Unfortunately, there's some pitting along the bearing surface and a groove where the seal lines up with the shaft. At least I have a better idea of how these boxes are constructed. Here's a picture:

Found another pickup power steering gearbox. The cross shaft was in much better shape:

 

[Diesel42]

Hey that housing came out awesome. Keep going the snow's headed your way!

 

[Stumpalama]

Where's the rest of this?
Did you give up?

 

[mikealeus]

What happened?

I was real interested in your build.

 

[SuperDuperCruizer]

What happened?

I was real interested in your build.

Life changes forced the project into hibernation... I know there's been a few threads regarding this. So, I'll try not to be redundant. The SST's are made by OTC and this would have been very difficult to do without them.

 

[SuperDuperCruizer]

Clamp the gear housing in a vice.

There's a mounting plate & bolts included in the tool set. The OTC part number for the Mounting Stand is [0002-00802] I used them to clamp the housing to a vice.

Tighten the adjusting screw until the end cover O ring is removed from the housing.

Lightly tapping on the pitman arm side of the cross shaft to remove the end cover.

 

[SuperDuperCruizer]

Remove the cross shaft by tapping the bottom end with a hammer.

Hold the power piston with your finger and turn the worm shaft clockwise. Then pull out the valve body and power piston.

The FSM states, "Do not disassemble the valve body. Do not remove the power piston nut from the worm shaft." ; however, I'll be installing new O rings and teflon rings on the worm shaft, power piston and valve body.

 

[SuperDuperCruizer]

Valve Body

I'm swapping portions of the valve body out with a better one I have on hand. Here's a picture of the valve body housing, teflon ring and O ring.

Used the SST to install the new O ring and teflon ring. The OTC part number for the Bearing Installer is [0002-00809]

After the new O ring, teflon ring, steel ring and roller bearing are installed the worm shaft can be installed.

 

[SuperDuperCruizer]

Worm Shaft

As with the other teflon rings, each of them sit upon a corresponding O ring similar in diameter. Here are the two O rings being remove from the worm shaft in preparation of installing the new parts.

Installed the teflon rings over the O rings using a home made SST. Found a flexible plastic ruler and cut it to the appropriate diameter such that it created a slight taper when the ends were taped together. The tape helped to keep the edge of the plastic from cutting into the teflon ring as it was pulled/pushed into place.

 

[SuperDuperCruizer]

Power Piston

Both the worm shaft and power piston rotate upon 44 recirculating ball bearings. Set the power piston on a bench in a stationary position as both the valve body and worm shaft are rotated clockwise together until separated from the power piston. If you do this, the 44 ball bearings will remain in the power piston instead of all over the floor. Turn the power piston upside down to dump out the ball bearings inside. Use an appropriate container to catch the ball bearings then remove the recirculating tube from the power piston.

After replacing the teflon ring within the valve body and the two teflon rings on the worm shaft, you're ready to reassemble the power piston, valve body and worm shaft.

With the worm gear assembled with the valve body, insert the worm gear 60% of the way into the power piston. Alternating between the openings, add a couple ball bearings at a time. With the openings facing upwards, begin rotating the power piston 5-15 degrees back and forth to line up the ball bearings within the grooves of the power piston and worm shaft. Repeat this until you've added 20 or so ball bearings using a dental pick to poke the ball bearing so they aren't any gaps between them. Residue may prevent the BB’s from settling into the valve body. If you have any residue on the BB’s, use a dental pick to push the BB’s in place.

After you've successfully placed 20 ball bearings into the assembly, you're going to start using the recirculating tube to prevent the ball bearings from settling to either ends of the power piston. If this happens, the ball bearings will emerge out of the top end of the power piston or block its rotation. Use two zip ties to secure the recirculating tube halves together. Adding one ball in each recirculation port, insert the recirculating tube, then rotate the power piston 5-15 degrees back and forth as before; however, changing the orientation of the assembly along the increasing number of ball bearings. Repeat this until you've added a total of 33 ball bearings to the assembly.

With the zip ties left in place to hold the recirculating tube halves together, place 9 ball bearings in the tube. Grease the 2 ball bearings and place one on each end of the tube to hold a total of 11 ball bearings in place within the tube. No more ball bearings should be left at this point. Place the exposed ball bearings within the power piston in such a way to facilitate the recirculating tube as shown.

Once you've inserted the recirculation tube, loosely attach the bracket to support the tube as you clip and remove the zip ties. With the zip ties removed, tighten down the bracket.

 

[SuperDuperCruizer]

Inspection & Repair

End Cover
Inspect the following for damage or wear.
1. Needle roller bearing
2. O ring groove

Here's a close up of the end cover and markings on the needle roller bearing. I couldn't find a vendor for anything similar to NTN HMK 3230V4 LS

Cross Shaft
Inspect the following for damage or wear.

1. Needle roller bearing running surface
2. Teflon ring contact surface
3. Dust seal contact surface
4. Power piston nut gear tooth contact surface

During disassembly, I observed the original dust seal was installed backwards. You can observe the cross shaft has a slight groove where it made contact with the surface. I'm hoping the new seal will make contact in a different position on the shaft and it will not be an issue. It appears this gearbox may have been previously rebuilt.