1981 CJ7 Restoration - 2018.10.27 - Leo Kahng

1981 CJ7 Restoration - 2018.10.27

Today was a day of tying up some loose ends and getting a little further with axle prep/disassembly.

One of the most psychologically bothersome things about this project is a stuck and broken bolt that holds down a clamp that secures the speedometer gear in the transfer case. The bolt broke off at the head when I tried to remove it.

Broken bolt head and retaining fork for speedometer gear.


I had managed to drill a hole into the bolt shank using a cobalt drill bit, which was big enough to insert a bolt extractor. I started to try turning out the bolt shank and SNAP - the extractor broke off almost flush with the bolt shank! This is one of the worst scenarios one could experience. The extractor (sometimes called an 'Easy Out') is made of hardened tool steel. I tried to grind through it with cobalt drill bits and grinding bits for a Dremel tool, but I just couldn't get very far. The best results were from the aluminum oxide Dremel grinding bits.

Started to make some headway with the Dremel grinding bits.


Some abused Dremel grinding bits and cobalt drill bits.


The most effective were these cone shaped aluminum oxide Dremel grinding bits, so I decided to go to Home Depot and pick up about 10 of them. While I was there, I saw this tungsten carbide grinding bit that was being advertised for grinding stainless and hardened steel. I figured, what the heck - $9? I'll give it a try.

Tungsten carbide Dremel grinding bit.


Grinding the extractor and bolt like a champ!


Much to my very pleasant surprise, the tungsten carbide bit ground out the extractor and bolt in a matter of a few minutes. The right photo above shows some of the outer shell of the bolt shank threads that came out.

After getting everything out and blowing out the debris with compressed air, I began carefully retapping the threads, which are 5/16" - 18 threads per inch. Going slow and moving a little bit forward then backing out, cleaning the tap, rinse and repeat, I was able to restore the threads.

Fresh clean 5/16"-18 threads - FINALLY!


After this whole ordeal, which only took about 30 minutes, I decided I would get back to dismantling the axles. Previously, I'd gotten the rear axles out, but in order to get the drum brake backing plates off, I had to either pull the hubs or remove the axle bearings.

Rear axles and backing plates.


I don't have pictures of this, but I tried using a large gear puller to remove the hubs - the outer side of the backing plates, then just take the plates off. Well, this proved to be an exercise in futility as I cranked as hard as I could and there was zero movement, and I thought I might break the gear puller.

The next method was to go from the inner side and remove the axle bearings. Easier said than done. I could not get a bearing separator on the bearings, nor could I get the axle into a press in a meaningful way, so I used a cutting wheel on a Dremel tool to cut off the bearing race, then used a hammer and chisel to smash the bearing cages apart to remove them from the axle. It took a bit of determination to get through the bearing races, as they are made from hardened steel. The bearing cages were easy to pound through. The axle condition was not important to me since I was replacing them anyway, so they took a bit of a beating, but it's not anything to be concerned with.

Deconstructed axle bearings for the rear.


Back to the front axles. Pulled the spindles off with a gear puller, then proceeded to pull the axle shafts, which came out very easily. I then hammered on the ends of the ball joints, which freed the steering knuckles with relative ease. The part I can't figure out is how to get the ball joints out of the steering knuckles.

Front axle pieces removed.


Actually, I got a fair amount done today. After the backing plate removal and front axle disassembly, I started tackling the pinion nuts and yokes of the front and rear axles, as well as the transfer case. I don't have photos of the transfer case pinion nuts and yokes, but they came off without much fuss.

The front axle didn't put up much of a fight either, however, the rear pinion nut - that's a whole different story. I've been using a borrowed tool from my friend Tim who created this awesome device from some bar stock. I placed it on the yoke with the driveshaft bolts, then put a 3-foot long steel pipe over it for support. Next, I took a 18" breaker bar with a 1-1/8" socket, placed another cheater pipe on the end of it, then tried to break the nut free.

Trying to break the pinion nut free.


I saw my friend's tool bending, then honestly thought that I was going snap my breaker bar in two - it took about everything I could give it and nothing would happen. I then took a blowtorch to the pinion nut for about 3 minutes, tried again, and it broke free - whew!

After getting the pinion nuts and yokes off, I pulled the pinion seals with a seal puller. This was fairly pain free. Enough for today.

Front (left) and rear (right) pinion bearings visible after removing the pinion seals. Interesting that the rear pinion bearing is made in Canada, even though it's a Timken.


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