All posts by hpeyerl

60 series PS conversion into 1972 FJ-40

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My 72 FJ-40 has transformed a lot since I bought it 9+ years ago… Lift, bigger tires, better winch, reskinning, new seats, dashbox, rear storage compartment, rollcage, etc etc. One thing that was waiting for attention was the steering. I’m not totally averse to armstrong steering but over the years, it was getting sloppier and sloppier. I tried rebuilding the center link, replaced ball joints, adjusted the steering box, etc etc… But you can’t escape the fact that the 40 series steering setup just has too many links, and coupled with 35 year old parts, and a really big steering wheel, invites slop.

A few years ago, I started collecting pieces for a power steering setup. I grabbed a pump out of a Supra at a wrecker, I even procured a minitruck power steering box, bracket, etc. Since I built an FJ-45 and did a minitruck PS conversion on that, I decided that, while it worked well, the basic steering setup was still a 40 series setup with many links which invite slop… One day, while Wayne was cleaning his garage, he offered up some 60 series power steering boxes for sale at an excellent price. So I bought one. Then I found myself with some extra money in my paypal account (due to t-shirt sales), so I bought some of Luke Porter’s 4×4 Labs steering arms. He asked how I wanted them reamed and since Peter Straub had a set of Chevy 1ton tie-rod end taps and reamer, I said “Chevy 1ton please” and they arrived.

A couple years later I decided I’d start by building a power steering pump bracket for my canadian spec F. I built a backing plate and started hacking some 1/4 rectangular section into a sort of swivel that could contain the pump… I didn’t like how that was proceeding, so into the box of random power steering parts it went and sat for another year…

Fast forward to November 2008. I decided this christmas vacation would be a good time to do this conversion. Since I had just finished and stabilized the 1HZ->1HDT transplant in my 1993 FZJ-80 I found myself without an active project. So I started collecting the final bits that I needed.

I would need to build a new tie-rod and a new drag link. So I arranged to borrow Peter’s taps and reamer. Turns out the reamer was broken during one of Bruce’s work parties so I thought I’d try to find the correct reamer to replace it. Not so easy. The correct reamer for Chevy 1-ton tie rod ends, is a “1.5 inch per foot” spiral cut tapered reamer; available from Summit Racing for on the order of $260. Turns out Peter still had the broken reamer and it was only the tip that broke and it was still serviceable. The taps are 7/8-18NS left and right hand taps. The correct tubing is 1.25″ OD, .219″ wall DOM.

The next thing I needed to procure was the tie rod ends themselves. After much web scouring, I found the popular application was a 1985 Chevy Blazer. That produced little in the way of useful part numbers while standing at the counter of Napa. 45 minutes of looking in the book and at pictures on their parts system, we came to the conclusion that a 1985 GMC Suburban-K2500 3/4 Ton 4wd had the right parts. So I came away with ES2233L and ES2234R outer tie rod ends. I also came away with a 25-9520 belt.

I also decided to lookup the details on Mark Whatley’s 60 series PS conversion in the July/August 2003 Toyota Trails to see what pitfalls I was likely to encounter. Turns out Tim Schoeland (sp?) also did such a conversion so I got some information from him as well. Mark Whatley said to contact him privately because he’d changed the process since he wrote the article. I did that as well but Mark was pretty busy over the christmas break so I didn’t end up hearing from him.

Approaching my winter vacation, which I had booked from Dec 19th to Jan 4th inclusive, I had all the pieces I needed. My vacation started and I got started by brushing 8 inches of snow off my truck before pulling it into the garage. I also bought some kerosene for my garage heater.

First order of business was to dust off my old power steering bracket mockup. I really didn’t like where it was going but the backing plate and standoffs looked good, so I ground off the pump mount that I’d whittled away on for so long and started rooting through my scrap bin. There I found some other abortion of a pump bracket from a Corolla that I picked up at the wrecker a while back. It had a salvageable pump mount section that looked like it could be cut off and welded to my backing plate. So I did that and tacked it into place so the pulley would line up with the water pump double-pulley and the harmonic balancer double pulley. Looked good. A bit of bracing and the pump was mounted in the right place. I went with the tensioner pushing down on the belt because I wanted as much belt-contact as possible to avoid squealing due to having 35×12.5″ tires. The fan shroud was in the way of the belt so I carved off a strip of that for clearance. There was good clearance for the hoses too, so the pump bracket was sufficiently done that I could move on to the rest of the truck.

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Next came gaining access to the old steering stuff. It was time to remove the tires, and drivers side fender. This really makes the whole job easier and only took about 15 minutes including dealing with some rusted in bolts that hadn’t moved in about 35 years.

Now with all of the old steering stuff in plain view, it came time to make it all disappear… I removed the shock so I could remove the shock tower, as that was going to be in the way of the steering box. I ground off the heads of the 4 rivets holding it to the frame, and started hammering on the rivets. After learning that a hammer will go where the eyes are looking and severely damaging my thumb, I managed to remove the tower. After popping off the tie-rod ends from the old steering arms, removing the center link, I was able to remove the tie rod, and cross link. The steering box was unbolted from the mount, and after dismantling the steering column, I was able to pull off the steering box and drag link. This is when I discovered my old-style steering wheel had a broken spoke. It’s possible that my bashing on the steering box was the last straw for it. But the steel support inside the plastic, that was welded to the hub, broke off. So the steering wheel was beyond servicable. More on this later.

After removing the steering box, I could also remove the steering box mount from the frame. More grinding and hammering and it came off… I now had cleared the way for progress. Next order of business was the knuckles and steering arms… One of the knuckles was weeping so I dismantled it, cleaned it, replaced the inner axle seal with a Marlin Crawler Magical Mystery Seal. Bearings looked ok so I left them. Reassembly included the placement of the steering arms on both knuckles. Then it was time to tackle the new tie rod.

The DOM tubing I got, while marked correctly in the store, had an ID that was too small. It had about .75″ ID. That’s too small for the 7/8-18NS taps. So on the tie rod, I measured the length and cut it to a distance about halfway into the threads of the tie rod ends as attached to the steering arm. I tapered the ends of the new tie rod and stuck a tap in. I didn’t have a tap handle big enough so I started with a 17mm socket which fit snugly. Then I used my click-type torque wrench to start cutting threads. After a couple of turns, the work became too tough and the 17mm socket started to skip. So I went to the old crescent wrench approach. I was able to get about 1/4 of a turn, then have to go backwards, and forward again, etc. Each end took me about 3 hours and generated a blister about the size of a dime on my palm. The hard part was because the tap decided to dive inside the hole so it was cutting away slightly more meat on one side of the pipe than the other.. It wasn’t so drastic that the threads weren’t cutting on the other side, but still… Definitely sub-optimal. The resulting tie-rod on the two rod ends over the diff, doesn’t turn evenly so with the knuckles hard to one side, the tie-rod contacts the diff unless I turn it 180 degrees and then it clears by a few mm. Definitely not awesome.

After discussing this issue with fellow club member, Jim Kelsall, he suggested the way to do this was to deploy the fabulous machine shop at his place of employ. So for the drag link, we drove to his office on a saturday and carved away the inside of each end to the correct ID for the taps on the lathe. Then used the tap to cut the threads on the lathe (not under power, but using a tap handle, with the end of the tap secured by a pointy item. I have no knowledge of things machining, but once the inside of the pipe was prepared, the cutting of the threads took about 15 minutes per hole, which is more like it.

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Once the tie-rod and drag link are painted, it was time to move on to the power steering box itself. The placement of this is a bit of a tradeoff. The distance from the center of the knuckle to where the drag link connects on the passenger side is about 9 inches. Optimally the pitman arm would connect to the drag link 9 inches from the center of the knuckle. This puts the steering box somewhat to the rear of the radiator shroud and, sadly, makes the steering linkage interfere with the fender support.

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If I’d moved the box further forward so the u-joint could clear the frame mount, I’d have the drag link at about 14 inches from the center of the knuckle which was more angle than I was comfortable with. Maybe that wouldn’t have been so bad. So the fender still remains an item of concern. But I need to deal with the steering column first.

For the steering column, the 72 has an old style steering column, which means the steering shaft lives in a housing. I need to find a GM pilot bushing (per Mark Whatley) and slightly machine it to fit. Then probably get a pillow block of some sort and attach it to the new steering box…

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Fellow RMLCA member Bruce Loewen offered a 60 series steering column he had lying around. This provided a good source of shaft/u-joint to allow me to finish the job. I cut the old steering column to length and used the upper shaft of the 60-series column at the top section of the tilt. This was just long enough to reach my old steering shaft. Welded the two together and now I had a steering column.

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Unfortunately, I wasn’t able to find the appropriate chevy pilot bushing per Mark Whatley. Even the old guy at the most renowned auto shop in town wasn’t able to come up with anything that measured even close. So Jim Kelsall to the rescue again and he machined a bushing that was 1.365″ x .752″ x 2″(approx) out of copper. This fit absolutely perfect inside the column. I drilled a hole in it and the column to mount a zerk fitting. The purpose of the zerk fitting is more to keep the bushing in place but having grease in there isn’t a bad thing either.

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After that, I mounted my old-style steering wheel procured from Mark Woytovich which was in terrific shape. This produced a steering feel with almost no detectable play. The wheel does move left/right about an inch or so but it turns out that’s just the rubber flexing on the garage floor… So the steering is very tight.

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Now it was time to start buttoning up. The next order of business was the fender. It needed trimming due to the location of the steering box, shock tower and u-joints. I knew the u-joint at the steering box was going to be an issue because it was right where the fender mount was. I tried to line up the u-joint to coincide with the center of the mount but some trimming was still necessary. I suppose it my steering column were longer then I could have got by without a u-joint there (if I found some way to mount a custom shaft to the splines of the steering box) but I wasn’t sure if the angle was going to be too steep. So I hacked up the fender. Eventually these fenders are being replaced with OEM fenders anyway so I didn’t try to do too good of a job.

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Finally, the shock tower. I had to move the shock rearward about an inch so I cut off the lower shock mount on the axle and moved it back further and welded it back on. Then I grabbed a spare piece of 1x1x1/4″ steel and built a new shock tower. This welded on the frame between the steering box plate and the fender mount.

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Filled it with fluid and took it for a drive. This is an improvement of several orders of magnitude… Very nice and handles beautifully… Testament to both the 4x4labs steering arms, new ball joints, fewer ball joints, Jim’s machining, and 60-series PS box… I can recommend this swap to anyone. It has little trouble turning my 35×12.5’s on dry pavement.

Note1: I was asked for more photos of the PS pump bracket so here they are:

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