SteveJ

Then the car is not the problem. It's either a component (stereo or speaker) or wiring issue.

Do you have the problem when the key is in the accessory position?

The $29 must have been in Canadian dollars. 😉

I found the Littelfuse brand strip fuses that should fit the VW link box above on DigiKey and Mouser. Apparently the style is called HSB, and they are available in ampacities that are suitable for the Z. I'll definitely consider it for when I build the engine harness for my 240Z.

Also I have thought about playing around with this: https://www.amazon.com/gp/product/B00902G49U It has four slots for fusible links and a plug that is connected to ATO fuses. It would be a matter of figuring out where to mount it to reach the battery.

@HusseinHolland I saw this on Reddit Just Rolled Into the Shop and thought of you.

There is nothing that would affect polarity at the transmission. Testing: Get the car where you can safely get underneath. Put the transmission in reverse with the engine off. Disconnect the reverse switch from the wiring harness. Use an ohmmeter to make sure there is continuity across the switch with the transmission in reverse. From the voice of experience: @Zed Head helped me figure it out with the reference drawings.

What do you mean by the wires on the reverse lights are switched? Where do you think they are switched: at the transmission or at the tail light?

I can't put my finger on it, but something about your solution appeals to me more than the one done by the IPO (idiot previous owner).

The problem is that for the one relay you need a dual coil and a suitable relay base. You won't find that in a Bosch style relay. If you are lucky, you might find such a relay made for another car, but you would still need to add the base if you can find it. You will probably end up using two relays or doing the smart thing and staying with the factory style relays.

Aftermarket quality on mechanical fuel pumps has been abysmal. I tried one on someone's car. I removed it and used the diaphragm from it on the old fuel pump. The old fuel pump was fine with the new diaphragm.

That was the change over to 78. Yes, you have different relays. The good news is both are available as new, old stock, (NOS) for reasonable cost. https://www.ebay.com/itm/115076416128 https://www.ebay.com/itm/113692357729 I purchased a clock from the seller in the past. I suggest you edit your signature (find it in your profile) to indicate the build date of your car. That way you will get more accurate replies.

You won't find a single relay to replace the EFI relay UNLESS you use a relay designed for the Bosch system. The nice thing is that you can still find the relays. Just look for the EFI relay on a Beetle. It's the same.

Given the wire sizes in the harness, 70A (alternator) and 30A (all others) would probably be appropriate. Blue Sea provides the fuse curves for their Maxi Fuses. https://www.bluesea.com/products/5143/MAXI_Fuse_-_80_Amp The curve is the same for each amperage as it's based upon percent of fuse rating.

If you want to push air through the fuel rail, disconnect the carburetors, first. New≠Good, especially for fuel pumps. See what @Zed Headlinked. If the fuel pump goes bad on my 73, I'll probably just use an electric fuel pump.

Odds are it's your fuel pump. If it has a bad check valve, it will never pump adequately.

First, I can't see what hose goes where. Second, don't waste time. Go out and get a hand-held vacuum pump. It can help you with bleeding the brakes and clutch in the future.

If you don't see fuel in the filter, the pump isn't primed. The thing about cranking the engine to pull fuel is that you'll drain the battery faster. You can repeat a few times. As I mentioned before, you can use a hand-held vacuum pump to pull fuel to the filter. If the mechanical pump isn't pulling, you'll know because the car will die if it's not pumping fuel.

One way is to take off the fuel hose from the outlet of the fuel filter and spray carb cleaner into that hose toward the fuel pump. Also, make sure there is fuel in the float bowls of the carburetors.

Did you prime the fuel pump?

Um, no. The lack of a pressure regulator would not cause that since fuel would flow freely. Is your electric pump oriented in the proper direction? I can't tell from the potato quality photo. Get some more light under there. If it's pointed backwards, it might block fuel flow. Also, do you have voltage at the electric pump? Describe the wiring you used on it. (Is it connected to the stock wiring or what?)

Mechanical or electric fuel pump? If it's electric, is it mounted near the tank, and do you have a filter between the tank and pump?

Yeah, I was scratching my head on the aluminum spacer, too.

ZCarDepot has the spacer, too. https://zcardepot.com/products/fuel-pump-spacer-plate-240z-260z

It needs the spacer. The spacer is an insulator, keeping the heat from the head away from the fuel going through the pump. I don't know what brand fuel pump that is, but don't hold out a lot of hope for it.