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View Full Version : Restoring Ham's '48 Wills 2WD; Progress - and we dodged a bullet this week!



LarrBeard
03-20-2015, 11:00 AM
A lot more little bits and pieces got done over the past week. Painting continued - fenders, grill, miscellaneous plates, steps are done and in plastic ready to go on. Hubs, brake drums and brake backing plates are done - ready to start putting brake parts on backing plates. The goal is to get a rolling chassis, mount the cab - then start finish work on the bed. The flywheel is back from the machine shop, and the clutch parts are here. We don't need the motor yet, so it stays at the machine shop.

Well, this week we had one of those moments where you get a sheen of sweat on your brow, your knees go weak and you want to check your undergarments. The differential and rear axle on the truck aren't the originals - I replaced the original read-end about 1973 or 1974 after a catastrophic bearing failure. The replacement rear-end was opened up, cleaned out very well and several questionable bearings were replaced. So, it really only had a year or so of use before the truck went into hibernation - or suspended animation. Now, when you start a job like this, there is an urge to take a little shortcut or two - after all the rear-end was "almost new". But, we knew there was probably some rust and corrosion in there, so we decided to open up for a quick cleanout. Well, when we opened it up - not only did it need a cleaning - we found one of those Oh-s#**things that could have ended the whole job had we not done things right.

The carrier is secured to the ring gear by 8 bolts, which in turn are safety wired in place. As you can note in the picture, the head has sheared off of one of the bolts, being held in place only by the safety wire. In addition, the safety wire, which we assume would normally be twisted together at the end, isn't secured - it looks like a piece of the wire is missing. Had we not caught this, the bolt head could have fallen into the ring gear, destroying it and the pinion. Timken rear-ends are rare - replacing this one would have been another major repair!

We had already decided to open up the transmission and look for interesting things in it. That was a great decision - maybe we'll just find dirt, grease and old seals.

51 CJ3
03-20-2015, 07:59 PM
Lucky break! It is a little spooky the missing wire didn't turn up.

LarrBeard
03-23-2015, 11:32 AM
I suspect the missing wire got ground up into atoms.

Once upon a time, a long time ago on my old ship - a routine sample of the lube oil in the main reduction gear came up with a heavy concentration of copper. Now copper in lube oil like that generally means that a bearing has eroded away and a shaft is eating out the bronze bushings. After a bit or worrying and looking, someone noticed that the copper screen on the outlet of the lube oil circulating pump was gone. Mystery solved.

Let's hope there are no aw "pooh's" in the transmission.

Thanks for the comment - hope you like the story. It's an ongoing soap opera.

51 CJ3
03-24-2015, 08:49 PM
I am trying to prepare myself to do my CJ3A so anything giving me an idea what to look for or how to do something is of interest to me since I have never attempted a project like this before.

Is that the "normal" way those bolts are safety wired? My background would have me doing 2 bolts at a time using twisted wire instead of single strand all the way around.

LarrBeard
03-25-2015, 07:30 AM
You asked:

"Is that the "normal" way those bolts are safety wired? My background would have me doing 2 bolts at a time using twisted wire instead of single strand all the way around."

First, a comment: My differential is a Timken differential, the least common rear axle in old jeeps of that era. It is a "clamshell" rear axle, it splits in two halves to get to the goodies (a PITA to get backlash set). The more common rear axle - and as far as I can tell, the only rear axle - used in the "CJ" type jeeps was the Dana axle, the one with a cover plate. (Another thing I've found in almost 50-years of Jeeping is that you can never say "never" or "always", the boys in Toledo did a lot of strange things).

I've never had to get inside one of the Dana axles, but most exploded views of rear (and front) axles are Dana units. The Dana axles may not have a set of bolts that need to be safety wired. Now, having said that all of that, I don't think it really matters all that much. An opinion; if you wired just two together - and you had a bolt head failure, the single bolt head hanging on a safety wire could sag into a loop - and the loop could (maybe) let the bolt head swing into the gears. If you loop through all the bolt heads, a broken head is like a bead on a chain - it just slides back and forth on the wire.

Now, there may well be a different reason to just wire bolts in pairs. I'm sure someone will tell us...

Good Luck and Keep Jeepin'

51 CJ3
03-26-2015, 08:10 PM
My background is in aircraft maintenance. I can only think of about 2 places where single strand is used. Twisted wire is used in aviation more to ensure a positive lock to keep bolts/screws/nuts from backing off.
If there is anything within about an inch or an inch and a half to damage then I would no longer want to safety them in pairs. A broken bolt head would likely flop around and the remaining bolt would not have anything to keep it from backing out. They could be daisy chained using the twisted method. Twisted wire is stiffer than single wire so I am not sure if sag would be problem if an end bolt broke. A broken bolt head in the middle would stay in place because it is captured in the twist. Having both a bolt and the safety wire break complicates the issue. To many "what if"s to claim one method is better than another.

I wasn't thinking about the differences between axles. Mine has the Dana.

Thanks for the reply,
Jeff