SteveJ

Then why two threads? Ballpark pricing was given in the first thread.

I love coming to this site and learning what I thought I knew was wrong. Thanks for taking the time to explain.

I love that groovy 70s music.

I also have seen the opposite. The battery was discharging on a friend's car, and the alternator "tested good". I said F the test results. We replaced the alternator (internally regulated), and the problem was gone. Apparently the testing apparatus did not properly check for a bad voltage regulator.

Also, post the supplier and part number. Maybe someone here is familiar with it. There are some smart people on here who may be able to give you an educated answer.

Remember that your homework before class on Tuesday is to read the EE section of the FSM and read about Ohm's Law. That way you can ask questions on the things you don't understand before you get to class.

Yeah, once you said your fuse blew when engine speed increased, I was thinking that you have a bad voltage regulator OR you might have an internally regulated alternator with a voltage regulator. Either case can cause an overvoltage. I hope you didn't blow out any components when testing when using the higher rated fuse. Life can be a mean teacher. You get the test first and lesson afterward. Here's the lesson. NEVER put in a higher rated fuse when you blow the specified fuse. The wire is rated for only so much current. Putting in a fuse with a higher rating to find a short may cause the wiring to burn up. (Okay, so I dodged that bullet in the past, but I'm not doing that again.) So why would revving the engine cause a fuse to blow? To understand, you need to know Ohm's Law (https://en.wikipedia.org/wiki/Ohm's_law) and read through the testing of the voltage regulator in section EE of the factory service manual. Go ahead. I'll wait. Done? Good. Now say you have a circuit with a 10A fuse. The effective resistance in the circuit is about 1.45 Ohms. You can calculate the current assuming you have 12 volts going through the system. (Note: Automotive circuits would be designed around 14 volts with some safety margin, but I'm taking some license with this example.) Look what happens if you have a bad voltage regulator that is allowing the voltage to go too high. So you stuff a 20A fuse in the circuit and a component that is rated for 14 volts is now seeing 18 volts for a prolonged period of time. That component might fail in a way that lowers the effective resistance of the circuit, causing it to blow with the 20A fuse, or the insulation on a wire could fail, allowing a short circuit to develop. I hope it wasn't either of those. If you really want to look for a short, use an ohmmeter. For the circuit you're interested in, find it in the fuse box. Remove the fuse. There is an upstream side and downstream side of the fuse. The upstream side has 12 volts when the car is on (or 12 volts constant for brake lights and some other circuits).The downstream side goes to the load. Measure resistance from the fuseholder on the downstream side to ground. If it's less than 1 ohm, there is good likelihood of a short somewhere. Things to watch for include bad corrosion in the exterior light sockets. The corrosion can bridge the gap between the positive and negative side of the bulb socket. This will lower resistance a fair amount and lead to issues like wires and the fuse box overheating. I forgot to add this. Here's an example of a wire ampacity chart for DC circuits: https://www.altestore.com/howto/wire-sizing-tool-for-12-24-and-48-volt-dc-systems-a106/ There are plenty more for marine applications.

I replaced the booster and master cylinder on my 240Z before, so I have my technique down.

I replaced the brake booster today. I discovered a little over a week ago that it had gone south on me. It's so nice to have power assisted brakes again.

RPM is important for voltage measurements. The FSM lists voltages for engine speed. For the tachometer, there is a resistor in the circuit. It is identified on page BE-3 of the FSM. There is also a ground and 12VDC source. Since the ground and 12VDC source are shared with other instruments, I would guess it's the resistor unless other gauges are acting up. Replacing it will probably require soldering in a new one on the old connector. 2.2Kohm 1 Watt would work. They have them at Frys, Amazon, etc. (Lifetime supply: https://www.amazon.com/Uxcell-a11101900ux0055-Metal-Resistor-Piece/dp/B015CHKSZW/ref=sr_1_4?ie=UTF8&qid=1493437627&sr=8-4&keywords=2.2k+ohm+1+watt+resistor) Without more testing, it's difficult to be sure if it's the alternator or voltage regulator. Rockauto has a closeout on a voltage regulator $12.52 + shipping. Their cheapest alternator is $22.06 +shipping, and that includes the core charge.

Bob Leitzinger wrecked his 510 at Road Atlanta last weekend. It happened right in front of me.

Well, Bob has been given his release from the hospital. I wonder if he's going to try to rebuild the car. All it needs is the new front clip.

That's the price you pay for having the guest house.

I finally figured out how to download the photos from Pages Manager.

I have seen photos of the car. @asim has a right-hand drive 260Z, so we do need to know the year. He will need a right-hand drive dash and steering column cover. The car looks to have suffered from years of neglect. Please post the year of your 260Z and the year of the 280Z that you acquired for parts.

Turn 12

How much resistance is there in the thermostat switch? Is the AC relay completely unplugged?

Please answer both questions.

That works. See the questions in the image.

Not without a wiring diagram.

I'm not sure. Since I didn't put the engine together, I didn't have a chance to take measurements. I'd have to research that. The combustion chamber is smaller, so I get higher compression.

N47 Maxima head

Yes, I do have a reason for the electric pump only. I don't want to remove the head and open up the window for the mechanical pump.

I finally got the photos from Friday online. https://stevescartography.wordpress.com/2017/04/24/friday-at-the-2017-mitty/

I was thinking of trying to mount a shroud on the radiator for the fan, but I haven't gotten around to it, yet. I know my fan clutch isn't in perfect shape, but I do hear the fan kick in still.