How to Rebuild a Saginaw Steering Gear Box (Detailed!) - Add Hydro Assist

Introduction

This tutorial provides a detailed guide on how to rebuild a Saginaw steering gear box, specifically focusing on changing out seals and bearings. Additionally, it includes instructions on how to tap and port the box for hydro assist steering. This guide is beneficial for those looking to maintain or upgrade their steering systems, particularly in vehicles like the 1997 to 2002 Jeep Wrangler TJ.

Step 1: Gather Necessary Tools and Parts

Before starting the rebuild, ensure you have the following tools and parts ready:

Tools Needed

• Impact driver or ratchet with a 15mm socket
• Hammer and mini cheater bar
• Torque wrench
• Adjustable magnet
• Snap ring pliers
• Seal and race driver
• Vice grips
• Drift punch
• Screwdrivers (flat and Phillips)
• Dead blow hammer
• Flashlight
• 3/8 drive socket
• Center punch
• Homemade spanner wrench (or purchased spanner wrench)

Parts Needed

• KOYO BH-2020 bearing
• Seal kit from PowerSteeringSeals.com (part number PSS.SB.JEP.004)
• Various O-rings, seals, and retaining rings

Step 2: Prepare the Steering Gear Box

1. Drain Fluid: Use vice grips to clamp the input shaft and turn the box over a bucket to drain excess power steering fluid.
2. Secure in Vice: Place the steering box in a vice, ensuring the jaws do not touch the sector shaft cover to avoid damage.
3. Center the Sector Shaft: Use vice grips to rotate the sector shaft and take note of the number of turns to find the center position.

Step 3: Disassemble the Steering Gear Box

1. Mark Adjustments: Use a center punch to make alignment marks on the adjusting nut and housing to maintain preload settings.
2. Remove Locking Nut: Carefully unfasten the locking nut using the spanner wrench.
3. Extract Sector Shaft: Remove the four 15mm bolts securing the sector shaft. If necessary, tap gently with a dead blow hammer to free it.
4. Take Out Retaining Ring: Use a drift punch to pop out the retaining ring and then carefully remove the piston cap.

Step 4: Remove Inner Components

1. Extract Piston: Use vice grips to rotate and push the piston out, being cautious of falling ball bearings.
2. Collect Ball Bearings: Ensure all 24 ball bearings are collected. Use a magnet if necessary to retrieve any that fall.
3. Remove Spool Valve and Seals: Unscrew and remove the spool valve along with its O-rings and seals.

Step 5: Clean and Inspect Components

1. Thoroughly Clean: Use brake cleaner to clean all components, ensuring no debris or remnants of old seals remain.
2. Inspect for Damage: Check the sector shaft, bearings, and other components for wear or damage.

Step 6: Reassemble the Steering Gear Box

1. Install New Seals and Bearings:
   • Lubricate the new O-rings and Teflon seals with power steering fluid before installation.
   • Use a seal driver to install the new bearing and seals without damaging them.
2. Reinsert Piston: Carefully insert the piston back into the housing, ensuring proper alignment.
3. Install Ball Bearings: Place the ball bearings into the housing, alternating between the different types (dark and shiny). Use a zip tie to hold them in place while securing everything.
4. Reattach Sector Shaft: Rotate the sector shaft to align with the piston holes and secure it with the four bolts.

Step 7: Tap and Port for Hydro Assist (Optional)

1. Mark Drill Points: Identify the locations for drilling based on existing features on the gear box.
2. Drill Holes: Carefully drill to the required depth (7/16 inch) for hydro assist ports.
3. Tap Holes: Use a quarter by 18 NPT tap to thread the holes, ensuring the threads are deep enough for a secure fit.
4. Install Plugs: Seal the holes with brass plugs and plumbers tape or sealant.

Conclusion

You have now rebuilt your Saginaw steering gear box and optionally tapped it for hydro assist. Ensure everything is securely fastened and free of leaks before re-installing the box in your vehicle. This process not only extends the life of your steering system but can also enhance performance. If you have any questions or need further assistance, feel free to reach out for clarification.