Steering Column Grommet Removal

Today the weather warmed up a bit and I was able to get outside and do some work on the truck. I pulled the steering column grommet out of the firewall. Mine is in really rough shape and I’d like to replace it, though I haven’t had much luck finding a replacement part.
Here’s the engine bay:

The steering column grommet is a boot that mounts into a cone-shaped hole in the firewall and has two holes; one for the steering column and another for the shift linkage column. I’ve seen pictures of some of these in decent shape. They angle downward parallel to the steering column outwards an inch or so. Here’s a close-up of what remains of my grommet. The bottom lip part that mounts into the firewall is intact, but the boot section that encloses the columns is gone.

I used a flat head screwdriver to pry the grommet from the firewall opening.

Clearly the grommet wouldn’t come free without removing the steering and shifter columns, so I cut the rubber with a pair of scissors.

Then I was able to pull it off.

Here are some detail shots of the top and bottom of the steering column grommet.

Here is a close-up of the profile of the grommet where it mounts to the firewall.

Disconnected the Generator

This morning I disconnected and finally removed the generator from the engine bay. I mechanically freed the generator last month, but it remained attached to the wiring harness until today.
Here is a record of the three electrical connections to the generator: black wire, white wire with black stripe, and white wire with red stripe. I’m not 100% certain this is how the wiring came from the factory, but it’s how I got it and will be the starting point when I reinstall the generator.

I used a 9 mm socket to remove the bolt that held the black wire in place.

The other two wires were mounted on studs with a lower nut and an upper nut sandwiching the wire connector onto each stud. For each of those, I used a 1/2″ socket on my socket wrench to loosen the top nut while holding the lower nut in place with a wrench.
I started with the white wire/black stripe.

And then did the white wire/red stripe.

I labeled the wiring harness so someday I can put this all back together.

And here is the generator, finally removed from the engine bay.

Horn Removal

This afternoon I removed and cleaned up the horns from the engine bay.  The 320 has two horns, one is a high tone and the other is a low tone.  Only one of the two is typically connected at a time, so you have a choice.
Here are the horns.  They are located on the passenger side of the engine bay, mounted on the frame just below and forward of the battery.  I believe these are the stock horns, but originally they would have had domes over the tops of them; these horns are naked.

I used a 1/2″ socket in my wrench to remove the single bolt that goes through flanges in both horns and attaches them to a bracket on the frame.

Here’s the bolt.

I labeled the green wire from the wiring harness, which will stay in the engine bay, and disconnected it from another short wire attached to the horn.

This is the bracket where the horns were mounted, just beside the passenger-side engine mount.

The horns were covered in dirt, grime, and some rust.

I used a wire wheel in my drill to start cleaning them up.

The difference was night-and-day.

I cleaned up both horns using the same approach.

Then I scrubbed each of them with some metal-prep, which should help to prevent any new rust from forming for a while.

Inside of each horn is an “L” for low tone and “H” for the high tone horn. I plan to try to bench test these at some point, and paint them before reinstalling.

Generator Removal

Today I removed the generator from the engine. Previously I started the process by detaching the adjuster arm that allows the generator pulley to act as a tensioner on the fan belt. What remain are the generator bracket that bolts into the oil filter/distributor side of the engine block and various electrical connections.
The bracket is attached to the block by four bolts. I used a 1/2″ socket in my wrench to loosen those bolts.

The lower rear (firewall side) bolt served a dual purpose, also attaching the battery ground cable to the engine block. After removing everything I put the ground back into place and loosely threaded in that bolt to make sure I put it back during reassembly.

Then I was able to liberate the generator from the engine block, with the mounting bracket still attached to the generator.

Here is a picture of the generator’s electrical connections.

Here are shown the two bolts that connect the generator to the mounting bracket. The bracket has holes on either ear, and the generator has two flanges, one just behind the pulley and one at the opposite end, which both have mounting holes.

I used a 1/2″ socket and a ratcheting wrench to remove the first mounting bolt from the pulley-end of the generator.

Then I removed the nut from the mounting bolt on the opposite side of the generator.

Which released the mounting bracket from the generator.

Here are a couple of shots of the generator mounting bracket.

Heater Hose Removal

Today I spent some time tidying up the engine bay. I removed the old heater hose which snaked from the rear of the engine block around toward the front.

The set-up was a bit curious, because there were no hoses connected to the heater core through the firewall. Also, since the engine came with what I believe to be the original cast iron fuel pump, which doesn’t have an outlet for a hose to the heater core, I plan to rationalize/correct/simplify the routing of heater hoses when I put this all back together. Namely, the outlet at the rear of the block will be connected via a short length of 1/2″ heater hose into the lower inlet of the heater core.

Then another longer section of heater hose will snake out of the upper heater core outlet, around the valve cover on the left side and turn right next to the thermostat housing and then run down into a new inlet connect on the new water pump.

Intake/Exhaust Manifold Removal

I spent most of today removing the intake and exhaust manifolds from the engine.

Here is a shot of the intake manifold as it sits on top of the exhaust manifold. The light blue shop towels are still in place from when I removed the carburetor and stuffed them into the intake.

As shown below, the manifolds attach to the head by a combination of six bolts and washers. In the first picture, on the end toward the firewall is the bracket one can use to lift the engine out of the engine bay.

I used some PB Blaster and a 1/2″ socket to loosen the bolts.

I removed all of the bolts. The second left-most mounting point was actually a stud.

I removed the 1/2″ nut and the washer from that stud.

Then I did the same from the right-most stud, which also mounts the engine lift bracket.

Here are a couple of shots of the engine lift bracket.

I used a ratcheting wrench to loosen the inside bolts because there was no clearance to get a socket into the space.

And did the same on the other side.

The top of the manifold came loose from the engine, but the bottom was still mounted to the exhaust below. The truck came without a full exhaust system. After a brief downpipe with a resonator the exhaust terminates under the truck and never makes it to the back bumper. At first I tried to loosen the bracket that clamped the exhaust manifold to that short pipe, to no avail. So, with nothing worth saving south of the manifold, I took more drastic measures.

The exhaust pipe didn’t put up much of a fight.

So with the manifold liberated from the exhaust pipe below, I was able to extract the intake/exhaust manifold successfully.

Then I pulled that short length of exhaust pipe from the exhaust manifold.

Here are some pics of the combined manifold, still assembled.

These two pictures show the four nuts that connect the intake manifold (upper) to the exhaust manifold (lower).

This is a look down into the two intake ports below the carburetor. There is an insulator and gasket that sits on those four bolts between the manifold and carb.

Here are a couple of shots of the engine on the driver’s side. Now with the manifolds and carburetor/air cleaner stripped away it looks pretty bare.

Next I separated the intake manifold from the exhaust manifold. I used a 7/16″ box-end wrench to loosen the nuts from the four studs at the corners of the intake.

After breaking them loose I was able to turn all four off with my fingers.

With those four nuts and washers removed, I was able to pull the intake manifold up and off the exhaust manifold.

The underside of the intake manifold that mates to the exhaust manifold has a cool, accordion shape. In the picture below is is caked in black carbon from combustion. Also between the two manifolds is a hot spot gasket that thermally separates the hot exhaust manifold from the cooler intake manifold above.

Here is the free intake manifold. It appears to have originally been painted Datsun blue like the engine.

Removed Oil Filter Housing

Later in the afternoon I removed and cleaned up the oil filter housing.  Modern engines typically have a screw-on plastic-shelled integrated oil filer that screws up into a mount on the engine from underneath.  The E-1 engine has a cartridge-style oil filter that resembles a modern one (though probably more primitive) with its outer shell removed.  The cartridge-style (paper) filter slides onto a shaft and is protected by a metal, distinctive dome-shaped housing.  This set-up is located facing upwards on the battery-side of the engine bay behind the generator and in front of the distributor, just below the spark plugs.

I used a 5/8″ socket to loosen the threaded rod that holds the oil filter housing into its mount.

When the rod came out I lifted it away and it brought the housing up with it. Below on the right is a shot of the oil filter and housing mounting point.

Here is the oil filter that was on the truck.

The filter housing itself was very dirty, but clearly had originally been painted in Datsun engine blue, so I decided to repaint it that color.

I sprayed it down with water and some Simple Green, and then used a blue scouring pad to scrub it.

There was a fair amount of surface rust on the housing, although it is very solid. I used some Metal Prep to treat the rust and bare metal surfaces. That’s as far as I got on this day.

Drained the Oil Pan

After I drained the fuel from the gas tank, I drained the engine oil. The oil pan is located right in front of the front frame cross-member, and the drain plug is right at the front and center of the pan.

I sprayed some Simple Green on the drain plug and scrubbed it with a stiff brush to clean off the grime and road dirt that had accumulated there.

With the head of the drain plug cleaned off, I used an adjustable crescent wrench to loosen the plug. The head of the plug was too large for any of my sockets.

After unscrewing the plug the rest of the way with my hand, the engine oil drained into my drain pan. It’s good news that the engine was in fact full of oil and the oil seemed to be in decent condition.

After the oil drained I replaced the drain plug.

I plan to find a replacement drain plug and copper washers if I can. More on that later.

Drained the Gas Tank

I drained the old fuel out of the gas tank this afternoon. The fuel tank is located at the rear of the truck, under the bed. You put gas in the truck through the rear fender on the driver’s side in the U.S. (not sure about elsewhere) so the fuel tank is located just below that, inside and below that fender.

There is a drainage plug at the bottom of the fuel tank. In the picture below the drive shaft is visible for reference. I sprayed some Simple Green on the drain plug to loosen up nearly 50 years of dirt, grease, and grime covering the head of the plug.

Then I used a stiff brush to scrub away at the drain plug, revealing its head.

I positioned a drain pan underneath the gas tank and used a 3/4″ socket on my wrench to loosen the drain plug.

After it loosened up I finished unwinding the drain plug by hand, and the gas drained out.

The good news is that the gas looks very clear and the viscosity is thin. I don’t know how long this gas has been in the tank, but I suspect the truck hasn’t run in many years, maybe even a decade or more. Just as I was getting a little nervous that my drain pan might not be adequate, the gas slowed to a trickle and stopped draining.

It was a pretty good quantity of gas, and had an amber hue to it.

I reinstalled the drain plug to finger tight, and then tightened it up some more with the 3/4″ socket.

A final shot of the gas tank drain plug.

And here is a shot down the gas filler neck. I tried to ascertain whether there was a lot of sediment inside the gas tank, but couldn’t really tell.

Fuel Pump Removal

This morning I spent some time removing the old fuel pump from the engine. This is not the original fuel pump that came with the E-1 engine, but instead looks like a J13 fuel pump that came on the later 520 trucks. Those two are interchangeable, but unfortunately I haven’t been able to locate either an E-1 or J13 aftermarket replacement mechanical fuel pump anywhere.

Here are some shots of the Nikki fuel pump. The rubber hose still attached to the pump feeds from the fuel filter and before that a hard line from the gas tank. The second outlet from the fuel pump which isn’t attached to anything previously was connected to a hard line going up to the carburetor.

Here you can see the fuel line connections and where the fuel pump bolts into the engine block.

I used a flat head screwdriver to loosen and remove the hose clamp holding the rubber fuel supply line to the barbed outlet on the fuel pump.

Then I used a 1/2″ socket on my wrench with 6″ extension that I slipped underneath the steering column to loosen each of two nuts mounting the fuel pump.

With those nuts removed from the studs on the engine block I was able to pull the fuel pump off the engine.

Then I was able to work the rubber fuel supply hose off the barbed fuel pump inlet.

Here’s a shot of the the fuel pump mounting plate and also one of the mounting point and studs.

I pulled off the spacer block…

and plugged up the opening in the engine block with a shop towel.