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The iron case was not painted. No sure about the cover.

I’ve never quite been able to figure out the thinking for putting bare iron and steel parts under the vehicles where they were subject to the worst conditions possible. Trans, rear ends, drive shafts, master cylinders, etc. I’ve always thought that the thinking might have been that the design life of the vehicles was only about 10 years or so and the parts would last that long if left to rust with out any protection. And after all, who but the poor mechanic was ever going to see the underside of the vehicle. I also feel that the brake plumbing with it’s crush steel flares and soft brass fittings and electrical wiring with it’s one-way snap together Wade connectors was also designed to only be assembled once and stay that way for the life of the vehicle. I can’t imagine that the goal of any of the engineering staff at GM ever designed with the thought in mind that these vehicles would be around 20-50 or more years.

Gene, I seem to remember from my days in the parts department back in the 50’s & 60’s, that GM’s policy was only to guarantee that the parts would be manufactured, or available for 10 years after release. Of course there were many generic parts that fit many years that were on the shelves for much longer than that. I do remember special ordering parts older than 10 years, which were still stocked in the warehouse but were no longer being manufactured.

Bruce, I'm restoring a 1950, 3604 and 1954, 3604. The first one I did several years ago and I started out using black paint on the under side but really didn’t like the look of that. Part way thru I discovered Duplicolor cast coat iron paint. That’s my choice now and on the second one which I’m presently working on it will be used on all of the castings and forgings. I’m restoring the underside of the ’54 and after I’ve cleaned and restored all of my cast and forged parts they will get the cast finish. Here’s just one source, but it’s available at auto parts everywhere now: http://www.tcpglobal.com/SprayPaintDepot/ItemDetail.aspx?ItemNo=DUP+DE1651 Even up close (couple of feet) it's hard to tell that it's paint as long as you don't load it on an inch thick! It sure looks a lot better than that red rust, which is inevitable if left bare as the original was and trying to keep the bare parts from re-rusting is dang near impossible. A lot of restorers are satisfied with everything under the vehicle in black like I started out doing, but as I mentioned, I wasn’t happy with the look because it looked amateurish to me. The front axles, spindles, arms and links were also bare and I’m using the cast coat iron paint on them also. All of the Chevy truck front beam axles that I’ve seen had an inspection/id mark of green paint dabbed on the front center of the beam. With the cast paint you can add this and it looks correct where it fades away if it has a black background. I don’t know if it’s correct but I think black paint does look proper on steel parts such as drive shafts, rear axle housings, tie rods. To this point I haven’t found a paint that duplicates the look of bare steel such as is used in the drive shaft and axle housing.
Denny Graham
Sandwich, IL

Maybe the engineers knew that it wouldn't be long before these parts had a nice coat of oil to protect them. I have scraped a lot of caked-on stuff off these parts over the years and never found a rusty casting or axle beam under the accumulated crud.

Mike

So you think all those leaks are designed into the Stovebolts, Mike????

Denny Graham
Sandwich, IL

The black paint over the raw casting usually lasted only a year or two at best. Was really a waste of time.

Chances are the black crud you are scrapping off is a dealer installed undercoating. My '51 was undercoated when new, and it was done thick! A lot of the overspray got onto the motor trans, and driveline as well. I've started scraping off under the hood and the fenders, as the car never sees winter, and it is surprising how protected the metal is even after 60 years. I was worried that road salt may have "soaked in" since the coating was never redone or touched up annually, but it seems to be perfect. Sometimes I wish the VCCA recognized "Dealer installed" and didn't deduct points for some options like this. Although the undercoat was supplied by an outside source, and was likely not "Chevrolet".

Undercoating was an approved material in 1951. Chevrolet sold it as a service accessory in a 55 Gal. drum under part # 986359.
There was no exact areas designated by Chevrolet as to what areas were to be covered. Each dealer and "applier" did what they thought was best.
Some even coated the valve cover. Most did under the hood area.
The 1949 and up cars came from the factory with the rear wheel house area coated.

1963 Chevrolet Custom Feature Accessories Catalogue

How does VCCA judge undercoating? I know someone that had his '72 Camper Special judged, and he lost points because the mirrors were on the truck, and not in the plastic bag on the seat as they were delivered from the factory. Does the coating have to be in the can, or can it be on the car!

That was one mixed-up judge. Cars are judged as they were delivered to the customer, not the dealer.

Some of the stuff the judges come up with on occasion totally amazes me.

And you won't be aware of it until your judging form comes in the mail weeks later. With some clubs you will never see a judging form.

Brewster,
The stuff I was scraping was the result of oil, dust, grit, oil, dust, grit, oil, dust, grit, oil, dust, grit, oil, dust, grit,oil..................................................................................................................................................................................................................................................................................................................................................grit.

Mike

Not entirely correct....

Although I don't doubt that the dealers shot undercoating from their 55 gallon drum all over everything in sight....

GM had very specific directions on which areas of the AD trucks that were to be undercoated at the factory.

The 1955-56-57 and up assembly manuals for cars do not show the body areas where the factory was to apply undercoating. This was because the body undercoating was done at the Fisher Body plant before it (the body) was shipped over to the Chevrolet assembly line.
The truck bodies were made by Chevrolet thus the undercoating was applied by the Chevrolet division. Question; The picture shows a 1954 cab, were the 1947-53 trucks undercoated in the same areas? I don't recall seeing any evidence of factory applied undercoating on them. In this part of the country they rusted in the lower cab areas in short order.

The 1957 passenger car assembly manual shows where to apply undercoating on the front fender inner skirt (wheel well) just behind the front wheel.

There were warnings in the Chevrolet Service bulletins after 1955 to avoid getting undercoating on certain areas such as the exposed drive shaft where it could cause an out-of-balance problem.

LOL

GM may have had specific directions for the undercoat installation, but those instructions never reached the eyes of the "undercoater' .... that I know.

By the way, the undercoater did use the 55 gallon drum .... with wheels attached to the bottom of the drum.

The "specific instructions" above were for the factory applied undercoating, not the dealer applied.
I remember our guys would apply a very heavy coating thinking they were doing a better job. Note how thin the factory applies was sprayed on. This was a case where more was not better

Here is a good shot of hood undercoating gone crazy....