What's this thing

As time goes by, I try to learn as much as I can about this project, be it restoration processes, assembly methods, techniques, anything. One of the more difficult things to wrap my head around, however, is literally what's sitting in the garage. That's right, I'm talking about the truck itself. Sure, I know generally how it works and what it's supposed to look like, but the truck is made up of a lot- a whole lot- of non original parts.

Some things I knew already, like how to decode the VIN number (that info is in the front of the LMC truck catalog) and that the rear fenders came from a '68 (or at least the side marker light on them did, as the year is stamped on them). There's also secondhand information. I was told (or heard) that the engine in the truck when we bought it came out of a '76, and the engine in the parts truck was a '72, and that when dad had it rebuilt, the top half of the '72 was mounted to the bottom of the '76. I have no idea if that's true or not, but that's the assumption I've been going off of when looking at parts. I've tried finding the casting numbers and looking them up before, but I don't think I ever found anything conclusive.

With any older vehicle like this, which many, many people have had their hands on, it's important to figure out just what is under the hood before buying parts. Of course, there are no records at all of what happened to this truck before my dad bought it in 1997. I have actually been able to find out some things, though.

New rotor in foreground, old cap and coil behind

I replaced the distributor rotor a few years ago, but the old one had "86 Buick" hand written in sharpie, which was a good clue. I looked up the numbers found on different parts, and this seemed to be consistent. This is very different than what was in the truck originally- this one has the coil built right into the cap, delivers more spark power then the original system, and does not use the old style points. These are good improvements, so I plan to keep this distributor. There's even a place I can hook up a tachometer if I so choose, and indeed I will someday! I was able to take the old one into the parts store with me, so that was helpful.


 

Parts truck transmission- Saginaw 3-Speed (probably)

The transmissions I have were a bit more difficult to identify. I had to go largely off their appearance to figure out what they are.  I'm pretty sure the parts truck transmission is a Saginaw 3-speed (a unit that has synchromesh gears), and the one in the truck is a Muncie, which doesn't have synchromesh, and I'm not sure it has gears anymore. It seems that putting the parts truck unit in would be an improvement, but I don't know exactly what I have, and the casting number search is inconclusive. (There's too much grease and grime on the one in the truck to read the numbers. My asssumptions are based on what I found at this site and ones similar to it.)


 (To see how a 3-speed transmission works, watch this video - you may want to skip to 2:52 if you already know how levers and gears work. And then this video about synchromesh- this one takes a few views to really get, but it's the best explanation I've found.)

The case is similar with my alternator. When I replaced a bad one back in 2007, I upgraded to one with a higher amperage output. Unfortunately I had no idea what it was, only that it worked. Turns out that it's a 12SI internally regulated 78 amp unit. What that means is that the new voltage regulator I put on with the new alternator is redundant. The new wiring kit which will eventually get put in will take care of that. Here's something I didn't know before- those fans on the front of alternators pull air through the unit from the back instead of the other way around. Something I never really thought about before.

Disgusting.

The differential / rear end is so coated with grime that I couldn't find any numbers where they should have been. At all. That's going to need a thorough cleaning once the bed comes off. It leaked when we got the truck and it still leaks now.










So now that I've thoroughly bored you with parts of the truck you don't care about (and admittedly, I've written about them here mostly for my own record), I'll share with you one more bit of info I've uncovered. The info plate on the drivers side kick panel has been painted over a few times, and probably can't be restored. However, I was able to read the original paint code. The truck's factory color was:

Light green. Not that I'm going to abandon my blue and white scheme, but it's interesting to know that.



One more update: I cleaned up that flywheel cover from the last post, but I failed to take a picture of it before I put it in the attic. Maybe another time.