The original air cleaner that came on my truck had been modified at some point. The “horn” inlet had been cut off. See below:
These modifications were pretty common, but I wanted to get an intact stock air cleaner to put back on the truck. A couple of years ago I cut out a small swatch of my stock air cleaner to use it as a sample to get some paint mixed in Datsun air cleaner blue.
Earlier this year I was able to acquire a replacement stock air cleaner from a 1964 320 that someone was parting out. It is in good shape, but has clearly been repainted at some point.
The inside of the new air cleaner had also been painted, but the lid was its original blue.
I used some Metal Prep and a Scotch Brite pad to address the surface rust, which was mostly on the lid.
Then I sprayed some Rustoleum white Clean Metal Primer on the air cleaner.
Here are the air cleaner body and lid in white primer.
I opened the can of paint Ace Rust Stop paint I had custom-matched to air cleaner blue and stirred it thoroughly.
In order to make the paint flow better and hopefully self-level, I added in around 15% of Penetrol and stirred that in really well.
I started with the lid, just using a foam brush to coat the inside of the lid and the wingnut and other accessories.
After the paint dried, I flipped over the lid and painted the outside.
The air cleaner body had a rubber gasket inside the area where the bottom of the air cleaner mates to the top of the carburetor. Here are some shots of that gasket from the bottom of the air cleaner looking up (left) and from the inside of the air cleaner (right).
As you can see, the gasket has a lip that rests on the underside of the air cleaner. I used a screwdriver to work the gasket down from the inside of the air cleaner out the bottom.
When I got the gasket out it was crusty, the rubber hardened, and broken in several places.
Here is some detail on the top of the gasket where it aligns with the air cleaner lip that tightens around the mouth of the carburetor.
With that rubber piece out I moved on to painting the body of the air cleaner, also just using a foam brush.