Mark Maras

Your vibration description is identical to one I had in my early 71, except mine came on at 80 mph +. I described it as having a 500 lb. bumble bee in the car. The vibration was too fast to be half-shaft u-joints. I tried new u-joints, but they didn't improve the vibration. After carefully cleaning the shaft and upon closer inspection, I found a bit of scuffed paint and the slightest hint of a dent. The dent was only visible in bright sunlight and at the right angle. Off to the local drive-shaft company it went. They retubed it and installed new Spicer u-joints. The only brand of u-joint they would guarantee to not screw up the balance at the time, I reinstalled tyhe shaft and never had any more trouble with it for the next twenty years..

I wouldn't want to be on the lean side of 14.7 at any time.

I believe there are two different snake oils for injection. One is a solvent that breaks down corrosion. The other is a lubricant that frequently uses mineral oil to lube the injectors. The one you've shown is a lubricant. Some products may contain solvent and oil but the little I've studied them, it appears it is either one or the other.

IF, (big if) the problem is electrical and is isolated to #4, it has to be located somewhere in the dist. cap, rotor, plug wire, sparkplug, and or any of their electrical connections. I'd pull the dist. cap (wires intact), and pull the plug wires. Using an ohm meter. check the resistance in the circuit between the contacts in the cap with the corresponding spark plug wire at the boot end. They should all be similar. Let's hope you find high resistance in the #4 circuit.

Depending on the mechanic's expertise, I'd lean towards the mechanic with a shop. If you have a Z repair manual, it will guide you through the head removal and replacement process.

I like the fact that they want to inspect the head before quoting a fee. I'm assuming you'd have to take them the cyl. head. Who will be removing and replacing the head?

Don't cut the choke cables. Loosen both cable attachment screws at the carbs. Push and pull the choke lever a few times. Is it easy or difficult to operate? If it's difficult, lube the cable and lever mechanism with oil. I pulled the carb end of the cables up, and sprayed WD 40 or CRC lube into the cable sheath ends and let gravity pull the lube down along the length of the cables. Then I looked to see if both nozzles were all the way up, pushed the choke knob forward and connected the cables to the carbs. Good luck and tell your Dad not to worry about the Canal.

When my nozzles started sticking in the down position, I removed the carbs and found the #1 bar warped. The ends were not parallel to their attachment points. A slight twist with two pairs of pliers on the bar realigned the ends of bar #1 with their mounting points. That ended the problem with the nozzles.

How's your knee doing?

It looks like something a pellet gun could cause. Is the paint original or a re-spray?

I too am guilty of using Series 1 &2. but using Type A &B is going to launch the same discussion by the same people because Nissan didn't use that designation either. I'll continue to use the Series designation because it is descriptive enough for U.S. Infidels.

I wrapped the ratchet straps under the car and over the roof.

I've used two folded towels against the glass, two 2x4s on the towels, and a ratchet strap or two to push the glass in.

Glad to hear you're doing well. You'll be in my prayers.

I'd start with a valve adjustment then a dry compression test followed by a wet compression test.

It can be reached from the right side with the car on jack stands and long tools.

Fender well, below the battery.

Hopefully, someone can tell Jalex how to test the fan coupling. After my coupling froze up I replaced it with a flex fan. There don't seem to be many flex fan fans around here but it was, IMO, an improvement over the stock fan. Nowadays I would probably go with an electric fan.

A temporary solution is to turn off the engine when you're not moving. Yes. you may have to restart it to move 20' before you turn it off again but I used this method for years in hot weather and traffic jams. It prevented overheating. Idling builds engine heat. BTW, what type of fan are you using?

Jalex's NGK plug wires are almost new. I like the idea of replacing the dizzy. Will the coil he's currently using (snort) be OK with the new dizzy?

Don't touch it if you don't have trouble starting it in cold weather.

Loosen the two choke cable screws on the carbs, push the choke knob to a centimeter from closed, and tighten the screws. You state the nozzles are up. Was that a visual check or a Braille check? That little flat-bar linkage piece that pulls down the nozzles can warp and bind the nozzle in the down position,

@jalexquijano When the choke knob is pushed into the off position are the nozzles pushed all the way up? Use a mirror to check them.

I always adjusted my choke cables to end up with a little slack before they pulled the nozzles. My reasoning was I wanted that extra bit of slack to push the nozzles all the way up even if the choke knob wouldn't go all the way to the off position. That did prevent the cables from pulling the nozzles all the way to the bottom but even here in the NW I rarely needed full choke in the winter.

Dry ice may do the trick. Freeze it and chip it off.