New Paint in the Engine Bay

Last week I cleaned up and prepped the right and left inner fenders in the engine bay. Today I spent the morning repainting the inner fenders.
Ordinarily the best way to paint an engine bay is to remove the engine and all of the ancillaries to prevent overspray. That isn’t in the cards for this project. So the next best alternative for me was to mask off the areas I didn’t want covered in red paint. I used some blue painters tape, newspaper for the larger areas, and aluminum foil, which I was able to form around the less-uniformly shaped areas and components.
I used blue tape to delineate the lower fender from the upper (which I’m not painting) and used foil to cover up the fuel line, brake line, and choke and accelerator cables.

I used the blue tape to cover up the corner of the firewall where it meets the fender and foil to cover the suspension.

Next I used a lot of newspaper to mask off the upper fender, external fender, engine, master cylinders, and front grille area.

The paint I’m using comes from APS Tower Paint in Wisconsin. That company will match just about any vehicle’s paint color from the color code your provide, including a 1964 Datsun. The color of my truck is Hustler Red, and Tower Paint sent me a spraycan of acrylic enamel paint for around $35. In total on this truck I used two cans of paint.

Following the directions on the can, I shook and rotated the can thoroughly and then applied a thin coat of paint, being careful to avoid runs.

After two more coats the color looked very nice.

Then I moved on to the left fender. It was a bit more complex, with more electrical wiring and the battery tray over there.

I used aluminum foil to encase the wiring harnesses and blue tape to mask off the upper fender and the firewall.

Then I used a lot more newspaper to cover the engine, distributor, oil filter mount, firewall, upper fender, and front panel. All that remained exposed was that lower inner fender area that was in the worst shape.

I also made sure to mask off the outside of the fender to avoid any overspray there.

Here is the left fender after the first light coat of Hustler Red.

And a couple more after subsequent coats.

After the paint dried overnight I removed all of the masking. Here are the finished right and left fenders.

And here is a shot of the renewed engine bay. The color turned out to be a really good match to the shiny exterior paint.

After painting the fenders I primed and painted the fuel filter bracket I removed from the engine bay.
The bracket was pretty rusty so I used a 3M stripping wheel in my drill to remove the rust.

After a coat of Metal Prep, I used some Rustoleum white clean metal primer.

Then I sprayed a couple of coats of Hustler Red on the bracket.

Right Inner Fender Cleaning

I spent this afternoon cleaning up and addressing surface rust on the right inner fender. This side has considerably more going on than the left side, so it was a more involved process.
Near the front the single hard fuel line emerges into the engine bay. At that point the fuel continues through a combination of soft rubber lines through the fuel filter and on to the mechanical fuel pump. I started by loosening the hose clamp and removing the rubber hose and plastic fuel filter from the end of the hard line.

Then I used a thin flat-head screwdriver to pry out the rubber grommet surrounding the fuel line hole. I will replace that grommet later.

About midway back was an L-shaped bracket attached to the fender by machine screws. This is the mount for the original glass-jar style fuel filter assembly (which is gone), but as far as I can tell this bracket would have originally been located closer to the front of the engine bay where the fuel line enters. I removed the bracket using a flat-head screwdriver.

Here’s a shot of the place where the bracket was located (note it was about as far back as the shock absorber below) and one of the bracket after I removed it.

Lower on the fender, and further back toward the firewall, there was another hole and grommet for the hard brake line that feeds hydraulic fluid to the front driver’s side brakes. I pried off that grommet also and removed it.

Here’s a look at some of the surface rust on the inner fender, at its worst down low near the suspension.

I sprayed the entire lower fender with Simple Green and used a Scotch Brite pad to clean away the grease and grime.

After a lot of scrubbing the fender looked much better.

I used a 150-grit sanding sponge to sand down the fender, focusing particularly on the areas with surface rust.

When I finished, the fender was much duller in sheen but the rust looked much less threatening.

I used some Metal Prep and a fresh Scotch Brite pad to scrub the exposed bare steel and any remaining surface rust.

The bare metal looked a healthy silver, rather than rusty-brown, when I finished.

Left Inner Fender Cleaning

While the exterior of my truck has clearly been repainted at some point and looks very nice, the engine bay is a bit of a mess. As I do the mechanical overhaul, I also would like to make sheet metal repairs and remove the rust from the engine bay. To that end, I spent this morning cleaning up, sanding down, and removing surface rust from the inside of the left front fender. There is no serious rust, other than the just behind the battery tray where it clearly rusted through at one point. That area appears to be very stable now.

Before I started cleaning, I did my best to pull the wires from the engine bay wiring harness up and away from the fenders to keep them from getting wet.

Then I used a spray bottle to spray some Simple Green onto the fender, and a green Scotch Brite pad to scrub the fender.

After some time and elbow grease, the fender started to look a lot better.

After the metal was clean, it became clear that there was some surface rust pitting the fender, particularly in the area of the battery tray. I used a 150-grit sanding pad to remove the paint and surface rust in those areas.

Then I applied some Metal Prep to another Scotch Brite pad and scrubbed it into the bare metal where I had sanded away the red paint. The Metal Prep chemically neutralizes any remaining rust and also leaves a thin, rust-inhibiting coating on the metal which helps to prevent future rust. I wiped away the excess solution using shop towels so it wouldn’t run down the panel or dry too thick.

Here are a couple of pictures of the left fender after I finished cleaning it up and treating the rust. The bare metal that has been treated takes on a whitish-grey tone because the protective film is almost chalky.

Engine Bay Tidying

I spent some more time this afternoon cleaning up the engine bay and the steering column and engine block, which still had a lot of greasy dirt on them.
Here is the engine bay before I started.

I wrapped the oil filter mount in aluminum foil to keep it from getting soiled.

I started with the steering column and shift linkage as well as the steering box, spraying them with Simple Green, which is a great de-greaser and cleaner.

I used a small wire brush to scrub the nooks and crannies of the linkages.

That worked pretty well at removing most of the gunk from the steering column and box.

So I went to work on the engine block on the passenger side, which is now accessible with the removal of the generator.

After some time the area was much cleaner.

Engine Bay Grommets

I plan to replace all of the firewall and fender rubber grommets in the engine bay. Some are just missing and others are dried up, crusty, or falling apart. The first step was to inventory all of the holes in the engine bay that need grommets to get a sense for what size I need to order and the quantities of each.  I used my calipers to measure the diameter of each hole in the engine bay so I can get the right sized replacements.
This post serves as a photo record of the engine bay grommets, starting in the front driver’s side corner, working my way back around the firewall toward the passenger side and back down the inner fender on that side. The area with torn metal that is bare in spots I believe is where the fuel filter bracket originally hung.
The first was down on the lower inner driver’s side fender.  The diameter of this hole was 3/4″

Moving back in the direction of the firewall, another grommet in the fuel line hole just over the wheel well.  This hole was 1 1/4″ in diameter.  Also shown in this photo, further back on the same fender from the fuel line grommet (near the steering column linkage) was another grommet in a hole in the fender with a 1 1/8″ diameter.

In the upper firewall above the shelf and next to the hood hinge, there was another grommet, this one in 1 1/8″ diameter hole.  Shown also in this picture is another hole, located to the right of the first one in the upper fender (without a grommet).  That hole was 7/8″ in diameter.

Then, pictured just to the right of the master cylinders, two small holes for the hood release (1/2″ diameter) and choke cable (3/4″).

And another small one on the other side of the steering column, 5/8″ in diameter.

Two grommets for the heater core inlet and outlet, each 1 1/8″ in size.

There were two more large holes in the firewall to the left of the heater core. I later determined that these were not original, had been drilled by a previous owner, and plan to weld them up.

On the passenger side of the engine bay, also up high above the fuse box near the hood hinge, was a larger hole with grommet for the engine bay wiring harness.  That one was 1 1/8″.

Another hole was located in the lower fender with grommet for the brake line.  That hole was 1 1/8″ in diameter.

And closer to the front of the engine bay in the upper fender over above the battery shelf, was a small 5/8″ diameter hole and grommet.  Not shown, there was another hole identical in size to this one on the opposite fender.

Below is a diagram I created of all of the engine bay holes that require grommets in my 1964 L320. The letters represent the different grommet sizes.  This should be reasonably consistent with 320s from other years.