Datsunpowers

I just recently purchased someone else's RB 240z conversion (Danger Will Robison!). Before I installed the engine in the car, I wanted to start the engine as it's been sitting for seven years. This engine would not start up and just kept backfiring. After verifying the Cam timing for the seventh time and checking CAS output signals. I could not find an FSM reference which way to orientate the CAS disk, so for fun. I just flipped the CAS disk over to give it a try. The engine fired up and ran like a champ. Problem solved! Here are a couple pictures showing the correct orientation for a RB25det NEO Series 2 engine set at 15 Degrees BTDC. I hope this saves someone else hours of troubleshooting!

Zev, a couple ideas come to mind. You said you tried larger pump jets, but it sounds like you are not getting enough accelerator pump fuel delivered to the intake stream when it transitions off of the idle circuit. With 45MM carbs with large ventures. When you open the throttle the air velocity slows way down, and the fuel will drop out of the air steam. You need a good shot of fuel to overcome this. Double check that the accelerator jets are squirting forward and at the same velocity. I had the same stumbling issue and two of the accelerator jets were clogged with debris on my carbs. The only way I found this was taking the carb of and watching the fuel come out of the accelerator pump jets. It drove me crazy until I found this issue. If you have a wideband controller installer you could see this lean condition when you open the throttle and transition off the idle circuit to the main fuel circuit. If you PM me. I can share my jetting chart that has worked for my 45mm Solexes. At least you have some more data as jets are expense. Hope this helps.

Mike the headlights didn’t have any polarity instructions with them. They did work out of the box in my 69 Camero. When I plugged them in my 240z they didn’t work. This is when I discovered the wiring polarity on the 240z is a non-standard H4 plug. With incandescent bulbs polarity doesn’t matter, but with LED lights it does. Here is a standard H4 plug and the non-standard H4 plug on the 240z. Switching two wires at the headlights switch corrects the polarity for a standard H4 plug. I am sure this applies to other H4 LED bulbs, but I don’t have experience with them.

For a couple years I have researched LED headlights for my 71 240Z. I wanted a headlight that had a great beam pattern and looked like a stock headlight. The headlight I choose was the Holley Retrobright LED headlights in Modern White from Headlight Revolution. Here is the link Holley RetroBright Classic LED Sealed Beam Headlights | 7" Round (headlightrevolution.com). The Headlight Revolution website has great information and testing results on LED headlights. The good news is the headlight fits and plugs into the stock headlight bucket without any modification. I have used these LED headlights for several months now and I really like them. I now enjoy driving the car at night and see the road and deer in front of me for a change! They are pricy, but you get what you pay for here. With these LED headlights the current draw is significantly lower than the stock headlight current draw. This means I can use the stock 240Z wiring harness by swapping two wires in the headlight switches. This swap changes the polarity needed for the LED headlights. I was going to use the Hella H4 headlights and did test them, but it would have required a new headlight harness to handle the increased current draw. Here are the different headlights I tested and amp draw. Here is the 240Z light switch modification that’s required to switch the headlight plug polarity for the LED headlights. This wiring modification is completely reversible. You will need the following materials. Materials needed: 1. ATO fuse holder with wiring extension 2. 15 amp ATO Fuse 3. 14 Gauge jumper wire 4. 2 Female bullet connectors 5. 2 Male bullet connectors 6. Voltmeter or Test Light for testing LED Jumper Wiring Modification with ATO Fuse Holder Wiring Procedure: (Pictures below) 1. Remove the steering column cover. 2. Unplug the Black wires from the Lower Headlight Switch and the High Low Switch. 3. Unplug the Red wires from the Upper Headlight Switch and the wire that runs to the headlight fuse block. This is the red common connection to the LH and RH Headlight fuses. 4. Connect the Red wire from the Upper Headlight Switch to one side of the ATO fuse holder. Note: you will have to extend the wires on the ATO fuse holder, so you can access the fuse holder with the steering cover on. 5. Connect the Black wire from the High Low Switch to the other side of the ATO fuse holder. 6. Insert a 15 amp fuse in the new ATO fuse holder. This is now your headlight fuse for both LED headlights. The headlight 12v power comes from the headlight switch. 7. Make a 2” long jumper wire with a male and female bullet on each end. 8. Connect Black lower headlight switch female bullet connector to the male jumper. 9. Connect the Red from the Common LH and RH Headlight fuses male bullet to the female jumper wire. 10. Now you have switched the polarity at the headlight plugs. To test your connections you can use a Voltmeter or Test Light. At the headlight plug you will have one common ground and 12v+ for the high and low beam. 11. Install the new LED headlights and adjust the beam pattern per the FSM. This so you get the best beam pattern and you will not blind oncoming traffic. 12. Reinstall the steering column cover very carefully. (The plastic screw holes in the cover like to crack and strip out very easily). LED Jumper Wiring Modification with ATO Fuse Holder Installed Upper Headlight Switch High Low Beam Switch Headlight plug electrical outputs before modification Headlight plug electrical outputs after LED wiring modification 240z FSM Headlight Wiring Diagram Holley Part Number 71 240z Holley Retrobright LED Headlights These Holley LED headlights bring the headlights up to modern standards with a classic look. The have a great beam pattern that really lights up the road when you're driving and don't blind other drivers. They come in different colors and the LED bulbs are replaceable. I choose the Modern White color vs. Classic White. They really have worked well for me so far!