Datsun 260Z Headlights

[SteveJ]

One thing to note here: If you change a 73 or 74 to an internally regulated alternator, you will energize the relay for the electric fuel pump all of the time. This will run your battery down, and if you are running an electric fuel pump, it will not shut down in the event of an accident.

Sometimes it's better to run the stock configuration.

[5thhorsemann]

One thing to note here: If you change a 73 or 74 to an internally regulated alternator, you will energize the relay for the electric fuel pump all of the time. This will run your battery down, and if you are running an electric fuel pump, it will not shut down in the event of an accident.

Sometimes it's better to run the stock configuration.

I have a electric pump on my 73 and don't have any of this going on Steve.

I went with the 60amp internally regulated alt and headlight relays at the same time and I endorse this modification/ upgrade, what a difference. I got the external regulator eliminator plug from MSA, do a thread search, lots of info here on that upgrade.

Edited September 8, 2012 by 5thhorsemann

[SteveJ]

I have a electric pump on my 73 and don't have any of this going on Steve.

I went with the 60amp internally regulated alt and headlight relays at the same time and I endorse this modification/ upgrade, what a difference. I got the external regulator eliminator plug from MSA, do a thread search, lots of info here on that upgrade.

Interesting. Does the electric fuel pump use the stock wiring? The battery in my 73 kept running down until I disconnected the harness for the fuel pump. It connects between the alternator and regulator. There is also a thread on here about the issue. IIRC, Dave Irwin started the thread. It's from a few years back.

Also note that the 74 has a different plug for the voltage regulator. It's a round plug that is unique to the model year.

[5thhorsemann]

When I bought the car it had a (really anoying) thumper pump wired in by the dealer to combat the vaporlock issues the 73 suffered from. I had to address the VL problems further when I went to the SU round tops, I replaced the thumper with a Holley Blue pump (just as anoying) but I have had no problems with the charging system. I will advise you to go with the headlight relays if you put in a 60 amp alternator, this will save you fuse box headachs later.

[porkbun]

I will advise you to go with the headlight relays if you put in a 60 amp alternator, this will save you fuse box headachs later.

As in the 240Z relays or make my own? Im still not sure if there is a difference for my 260 and something is bound to go wrong if I make it myself. Right now, the headlights are pretty bright and white, but only work on the high beam setting, and I try not to leave them on for very long.

About starting, turns out my battery had a bad cell, so I bought a new one, but Ill have to see if thats really the problem over the next few days

Edited September 8, 2012 by porkbun

[SteveJ]

The headlights for the 260Z have a different connector from the 240Z, so you would have to modify the relay kit that Dave Irwin sells (through MSA) to work.

As for not working on the low beam, that is likely a problem with the high/low beam switch located in the turn signal switch. Dave Irwin (Zs-ondabrain) will clean and rebuild your switch for a nominal fee.

[5thhorsemann]

As in the 240Z relays or make my own? Im still not sure if there is a difference for my 260 and something is bound to go wrong if I make it myself. Right now, the headlights are pretty bright and white, but only work on the high beam setting, and I try not to leave them on for very long.

About starting, turns out my battery had a bad cell, so I bought a new one, but Ill have to see if thats really the problem over the next few days

I was going to buy Daves kit, but ended up just making my own, it was a time and impatients thing. It is after all is said and done, a really simple circuit to build, although Daves is cleaner than my off the reel wiring. The problem with putting a 60 amp alt in a car with undersized wiring for the original 30 amp gear is clear.

I would think your new headlights likely draw more current than stock 70's bulbs did, so you are already taxing the wiring. The added stress on the wiring of a 60 amp alternator will surely cause a meltdown somewhere if you are already seeing "hot spots".

When you go the relay route you are only driving relay coils with the stock wiring, the entire 30 amp circuit that supplies power to the lamps is new. I used 10 AWG stranded to build the entire lamp circuits and supplied the relays with 8 AWG stranded and a 30 amp breaker rather than fuses. I now enjoy total peace of mind where the headlights are concerned.

[porkbun]

Im thinking I might just go with a 50amp alternator instead, but I dont thats the problem anymore. The battery with bad cell(s) is in the car right now and gives off about 12.41V when stopped and 12.86+ when running. When I first turn the car on it goes up to 12.46V and the voltage keeps growing ( I forgot to test it before turning the car off), so the alternator is charging the battery, but after a few days, Ill try and start the car and the battery will be drained (this all started after I left the rear defogger switch on). Now I unplug the terminals when I turn the car off and I havent had any more battery problems. How exactly do I conduct the battery spark test when plugging in the terminals and pulling fuses? I still need to check to see if the alternators voltage is externally regulated.

[SteveJ]

Unless your accessory relay contacts are stuck closed or someone re-wired the accessory circuit, leaving the rear defogger on couldn't drain the battery.

As for testing the electrical system, use a multimeter with a 10A range for an ammeter. There is a Klein Tools MM200 at Amazon.com for a reasonable price. You can easily learn how to use an ammeter by searching online.

Please note though, that a bad voltage regulator can cause the battery to drain when the car is off. If you look in the EE section of the FSM, you can find the location of the voltage regulator. If you need more of a visual, go to rockauto.com and find the voltage regulator for a 260Z.