beermanpete

Perhaps they would but that won't tell us anything about the position of the piston nor will it help set the ignition timing which is the purpose for the marks on the damper.

What does the cam sprocket positon have to do with the timing marks on the damper? The timing marks on the damper indicate cranckshaft positon with with respect to the #1 piston.

No need to double the vacuum. This one is straigth up.

Using the engine as a vacuum source will be too unstable to get reliable results. Use a vacuum pump so you can set the vacuum and leave it while you get the readings you want. Try to keep the engine speed constant as well, preferably at a slow idle so the centrifugal advance stays fully retarded.

I interpret the two lines in the charts as a tolerance window. If your distributor's performance is within the lines it is good. Be aware that the RPM and angles indicated are for the distributor (not the engine) and are intended for use with a distributor testing machine (distributor out of engine). For checking the timing curve in the car you need to double both the RPM and angle.

This diagram suggests that the alternator has been upgraded to an internal regulator type. This means the yellow wire is at battery voltage at all times. It is possible that the alternator has failed in a manner that has shorted the "S" terminal to ground. Check for a short from the "S" terminal to ground.

There must be a short to ground somewhere to melt the wire like that. The bad fuse may or may not be related. Since the fuse opened the wire should have been spared. Follow the burnt wire to the point where it is no longer burnt is about all I can come up with at the moment. Perhaps there is a cut in the insulation at a clamp point or where the wire passed through a hole in the body. The yellow (burnt) wire has about 6 volts on it when the engine is running and goes to the regulator, fuel pump relay (as Zed and Steve said) and the interlock system if it is still there. I don't know what the splice to the white wire is for but it does not look factory to me.

Does your car have an alternator upgrade installed? The wiring does not look like it matches the 260Z schematic.

The neutral switch is only used for the seat belt light and warning buzzer. The schematic indicates that leaving those two wires open would be the way to go.

Progress! Excellent! Let us know how it works once you finish correcting the problem you found.

If the green/blue wire goes to 0V when you turn on the light switch there is a bad connection upstream. If there is still voltage at the fuse when this happens there is a bad connection in between those two points.

You need to find the point where the voltage falls to 0. If the circuit and all its connections were good and there was an overload that could take the voltage at the switch to 0 the fuse would blow. If there is a crossed circuit that circuit should be coming on and you would know which circuit it is. Since you have not indicated that something unexpected comes on when you turn on the lights it seems more likely there is a high resistance connection somewhere that is dropping the voltage. Another thing that might help, turn on the light switch and feel the wiring for hot spots. A high resistance will get hot and you might be able to feel the heat while it is on.

I suspect your interaction with the turn signal indicator in the tachometer is from an open ground in the meter as there is no other common circuit node, especially since you have disconnected/removed the marker lamps. How have you verified your fuses? Visual inspection is not fool proof. Measure them with an ohmmeter or, better still, measure the voltage to ground on both sides while the load is applied (lights on). If the fuse or its clips are bad the voltage will drop across the fuse, i.e., 12 volts on the battery side and 0 volts on the load side. To test the connections along the way use a similar method: Turn on the circuit (after you reinstall the lamps) and measure the voltage along the circuit path. Start at the fuse (or the battery if the fuse does not have 12 volts on the battery side) and look for the point at which the voltage drops more than a tenth of a volt (0.1V) or so. You should find a point at which the voltage suddenly drops to 0. Even a tenth of a volt drop is a lot considering the load current is only a few amperes. However, the lamps will light with a volt or two drop so don't get hung up on a minor drop for now. Clean them up if it is easy, otherwise come back to them later after you find and fix the "real" problem.

Perhaps I am using the wrong terminology. The o-ring has to be held between the tank and the sender unit to seal. Either the lock ring or the tank has ramps (wedges) that the other half rides on to make the seal when you rotate the lock ring. As you tighten the ring those tabs (shown in Ramsesosirus's photo) go past the end of the ramps and fall into a depression which prevents the lock ring from rotating the other way.

It has been a while but I think you need to turn it until the high points go past the ramps so it cannot back out. Use a lever and grab it by the tabs across the ring to turn it smoothly rather that using impact.

Another issue related to the belt slipping is oil on the belt from an oil leak. Make sure everything is clean and dry. I would say it is normal for the system voltage to drop when you turn on the headlights and/or heater fan while at idle. The alternator will only output one third to one half its rating at idle and can't "keep up" with the load. When you race the engine does the system voltage rise?

Those tires are small and stretched. It looks like they are 195s, best that I can tell from the photos. This keeps them away from the spring and strut tube. Also, that car has coilovers so there is more room for the wheel and tire in the inboard side. Since this is the look you are after try contacting the car owner and the shop where it was made. They will likely tell you what they did and what parts they used.

The wheels are designed to mate to the mounting flange so, no, there will not be any restrictions due to the flange size. Regarding wheel and tire size combinations: We have (and many others have as well) 15" x 7" wheels with 225/50-15 tires that fit on a stock car with no problem. However, the fit is close so the wheel offset/backspace is critical. The offset needs to be zero for this size combination to fit. The limiting factor on the inside is the spring and its perch. The tire sidewall will rub on the spring perch if the wheel is too far inboard. Using an 16" or 17" rim should allow using an 8" wide rim if the aspect ration is less (35 or 40 perhaps) which will result in a similar tire diameter and cross-section width while achieving a larger tread width (tire sizes are cross-section, not tread width). The wheel studs and nuts can be a bit tricky on the Z due to the uncommon thread size (M12 x 1.25). Changing the studs to an M12 x 1.50 allows for a better selection of lug nuts but is not absolutely required. We installed ARP studs made for a Camaro/Firebird that fit without modifying the hubs that are M12 x 1.50 and 3" long. While this is a bit long for closed end nuts there is a shorter version available and they can be shorted if needed.This allows a much better selection of nuts from common sources.

The 16 mm "spacer" you show is the factory wheel mounting flange. The 8 mm spacer, as you already found out is to allow the wheels to clear the brakes. The need for the spacer is wheel dependent but not necessarily related to the offset of the wheel. The shape of the "spoke" section of the wheel that connects the hub to the rim is what matters. Larger diameter and width wheels typically will clear the brakes even when they have a zero offset, especially the modern designs.

Not necessarily. Find TDC on the compression stroke for the #1 cylinder independently of the distributor and timing marks on the harmonic damper. Start the firing order for the plug wires from which ever position in the cap the rotor is pointing to. If you still have points set the ignition timing using the "dead timing" method (after checking/setting the point gap). Also, I don't see any confirmation in your posts that you have spark. Make sure you have spark at the plugs before going crazy with the timing and firing order. Perhaps there is a problem in the primary wiring.

Not necessarily. Find TDC on the compression stroke for the #1 cylinder independently of the distributor and timing marks on the harmonic damper. Start the firing order for the plug wires from which ever position in the cap the rotor is pointing to. If you still have points set the ignition timing using the "dead timing" method (after checking/setting the point gap). Also, I don't see any confirmation in your posts that you have spark. Make sure you have spark at the plugs before going crazy with the timing and firing order. Perhaps there is a problem in the primary wiring.

Finish coatings are thin and generally will not hide surface flaws such as scratches and pits. Most finishing shops don't perform any polishing prior to the finishing you ask for. My experience with finishing is: You get out what you put in.

We use the kit from drivetrain.com. It works fine but the rear bearing for the counter shaft was the wrong size. Maybe it was for the early "A" transmission (we have a "B" transmission).

Hmmm...The 3 A fuses in the ammeter shunt are for the ammeter only, not the other circuits. Does anything work? Headlights? Horn? Brake lights? Bueller?

Check the ammeter shunt.