Installing Power Steering on FJ40
I have a Toyota/Lexus repair shop. I work on a lot of Landcruisers, but this was my first power steering conversion. I installed this saginaw power steering conversion on my 1978 FJ40. The kit I installed was purchased from Man-A-Fre. There are cheaper ways to go for parts, but this kit comes with a rebuilt gear assembly and pump instead of having to find used ones, which is what some kits require. This is probably the best modification I have done on my Landcruiser, although the shackle reverse ranks right up there also. The vehicle tracks perfectly straight at any speed, no wander at all. At 70 mph I can take both hands off the wheel and there is no insecure feelings whatsoever, outside of the fact that I'm traveling at a high rate of speed without my hands on the wheel. I have driven several FJ40s over the years and not having to white-knuckle my grip on the steering wheel at all times is a giant stress reliever, that's why this conversion is so great, it brings back the fun of driving an FJ40. This is in my opinion, the way Toyota should have done the steering in the first place.
First things first. Remove the front bumper, grill and radiator. Next, remove the original steering gear, relay rod, drag link and center arm (see figure 1). Just a little bit of slack in all of these pieces adds up to a lot of slop in the steering, that is why we don't want them around anymore. Don't remove the tie-rod link, unless your tie-rod ends are worn, this would be the best time to replace them if needed.
(figure 1)
Now is the most important part of the conversion, placement of the new steering gear bracket. The bracket gets welded to the frame rail ahead of the front crossmember. In my case it actually gets welded to the frame rail and shackle reverse bracket that was previously welded to the frame rail during that mod. I temporarily bolted the gear assembly to the bracket, then used a large c-clamp to hold both pieces to the frame rail to figure out where I wanted it positioned (see figure 2). I then marked where to drill a hole for the sector shaft to pass through the crossmember. I used a hole saw to drill a hole in the front, then backside of the front crossmemeber. Once that was done, I marked the position of the bracket, then removed the gear from the bracket and tack welded the bracket to the frame. Now is a good time to figure out how to get access to all four bolts that hold the steering gear to the bracket once the plate is welded to the frame. Some holes will have to be drilled and maybe some grinding will have to be done as well (see figure 3). After you are completely sure that all bolts can be accessed it is time to permanently weld the bracket.
(figure 2)
(figure 3)
To install the input shaft, I cut the end off the steering column shaft with a hack saw. Now the bearing support has to be installed to the firewall before welding the input shaft to the steering column shaft. Once I had the input shaft slid onto the column shaft in the desired position, I welded the input shaft u-joint with two short beads 180 degrees apart (see figure 4). I also had to loosen the left front motor mount and rotate it's position ~25 degrees so it would clear the input shaft.
(figure 4)
(figure 5)
There is a stub shaft that connects the other end of the input shaft to the steering gear. The front u-joint slides on to the stub shaft and is tightened with set screws (see figure 5), that is the stub shaft protruding through the front crossmember hole that was cut earlier. The stub shaft attaches to the steering gear with a clamp (see figure 6). You access the clamp bolt through a factory made hole in the side of the frame rail.
The pitman arm that came with the kit is for a Jeep with a two-inch drop. There are four flat splines spaced 90 degrees apart that prevent mounting on the pitman shaft in a straight rearward position. If the pitman arm is mounted with the flat splines in place, the pitman arm will contact the leaf spring in a hard left turn. Chuck the pitman arm in a vise and use a triangular- shaped file to file the flat splines away. Now count the number of turns lock to lock by turning the steering wheel. Reverse the wheel exactly half the number of turns determined before, now the gear is at the center position. Install the pitman arm with the center line of the arm parallel to the center line of the vehicle (pointing directly at the rear bumper). If needed, remove the steering wheel and mount in the center position. Next, install the relay rod to the pitman arm and tie-rod link. Figure 7 shows the pitman arm and relay rod installed and the steering gear in the center, straight-ahead position. I adjusted the length of the relay rod until both front tires were pointing straight ahead with the steering gear centered.
(figure 7)
The mechanical part of the conversion is finished and next comes the hydraulic part. It is pretty straight-forward. Mount the pump bracket and pump to the engine, then attach the hoses and secure the hoses with brackets to the fender well. The kit came with a narrow groove pulley for the pump which is way too narrow for the wide belts that Landcruisers use. I bought a wide groove pulley from Man-a-fre that allowed me to use a wide belt which I had to measure the length of and get aftermarket. My Landcruiser has the original engine and the belt I used is number 15A1315 Gates Green Stripe.
Now reinstall the radiator, grill and bumper. Fill the pump with power steering fluid and bleed the system. Then enjoy effortless steering that tracks straight and true.
I hope this helps with your conversion. I read a few tutorials that I found on the web before I attempted this and I gleaned several helpful tips from all and I hope this adds something to all of those tutorials as well.
First things first. Remove the front bumper, grill and radiator. Next, remove the original steering gear, relay rod, drag link and center arm (see figure 1). Just a little bit of slack in all of these pieces adds up to a lot of slop in the steering, that is why we don't want them around anymore. Don't remove the tie-rod link, unless your tie-rod ends are worn, this would be the best time to replace them if needed.
(figure 1)
Now is the most important part of the conversion, placement of the new steering gear bracket. The bracket gets welded to the frame rail ahead of the front crossmember. In my case it actually gets welded to the frame rail and shackle reverse bracket that was previously welded to the frame rail during that mod. I temporarily bolted the gear assembly to the bracket, then used a large c-clamp to hold both pieces to the frame rail to figure out where I wanted it positioned (see figure 2). I then marked where to drill a hole for the sector shaft to pass through the crossmember. I used a hole saw to drill a hole in the front, then backside of the front crossmemeber. Once that was done, I marked the position of the bracket, then removed the gear from the bracket and tack welded the bracket to the frame. Now is a good time to figure out how to get access to all four bolts that hold the steering gear to the bracket once the plate is welded to the frame. Some holes will have to be drilled and maybe some grinding will have to be done as well (see figure 3). After you are completely sure that all bolts can be accessed it is time to permanently weld the bracket.
(figure 2)
(figure 3)
To install the input shaft, I cut the end off the steering column shaft with a hack saw. Now the bearing support has to be installed to the firewall before welding the input shaft to the steering column shaft. Once I had the input shaft slid onto the column shaft in the desired position, I welded the input shaft u-joint with two short beads 180 degrees apart (see figure 4). I also had to loosen the left front motor mount and rotate it's position ~25 degrees so it would clear the input shaft.
(figure 4)
(figure 5)
(figure 6)
There is a stub shaft that connects the other end of the input shaft to the steering gear. The front u-joint slides on to the stub shaft and is tightened with set screws (see figure 5), that is the stub shaft protruding through the front crossmember hole that was cut earlier. The stub shaft attaches to the steering gear with a clamp (see figure 6). You access the clamp bolt through a factory made hole in the side of the frame rail.The pitman arm that came with the kit is for a Jeep with a two-inch drop. There are four flat splines spaced 90 degrees apart that prevent mounting on the pitman shaft in a straight rearward position. If the pitman arm is mounted with the flat splines in place, the pitman arm will contact the leaf spring in a hard left turn. Chuck the pitman arm in a vise and use a triangular- shaped file to file the flat splines away. Now count the number of turns lock to lock by turning the steering wheel. Reverse the wheel exactly half the number of turns determined before, now the gear is at the center position. Install the pitman arm with the center line of the arm parallel to the center line of the vehicle (pointing directly at the rear bumper). If needed, remove the steering wheel and mount in the center position. Next, install the relay rod to the pitman arm and tie-rod link. Figure 7 shows the pitman arm and relay rod installed and the steering gear in the center, straight-ahead position. I adjusted the length of the relay rod until both front tires were pointing straight ahead with the steering gear centered.
(figure 7)
The mechanical part of the conversion is finished and next comes the hydraulic part. It is pretty straight-forward. Mount the pump bracket and pump to the engine, then attach the hoses and secure the hoses with brackets to the fender well. The kit came with a narrow groove pulley for the pump which is way too narrow for the wide belts that Landcruisers use. I bought a wide groove pulley from Man-a-fre that allowed me to use a wide belt which I had to measure the length of and get aftermarket. My Landcruiser has the original engine and the belt I used is number 15A1315 Gates Green Stripe.
Now reinstall the radiator, grill and bumper. Fill the pump with power steering fluid and bleed the system. Then enjoy effortless steering that tracks straight and true.
I hope this helps with your conversion. I read a few tutorials that I found on the web before I attempted this and I gleaned several helpful tips from all and I hope this adds something to all of those tutorials as well.
posted by Michael Potter @ 12:54 PM
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