adivin

Follow up to this. I removed the front carb and recentered the butterfly ever so slightly to make it close completely. There was a very slight gap on the bottom half of the butterfly plate. You really couldn't see it unless you put the carb up to the light and looked through. I didn't think it would make a difference, but sure enough it did. The car will now idle as low as I like.

I did that and noticed a slight ring of light on the bottom half of the butterflys. The only thing I can think of is that they need to be re-centered so there is no light shining through, if that's possible.

Nope, all the other screws are completely out of the equation.

Ok, I got the 240z running after several years. I cleaned up and went through the SUs. I used the ZTherapy video as my guide. I initially chased some vaccum leaks, and got the idle down from 1250 to 1050, which also took care of the lean condition. Both carbs are synced and pulling 10 on the sync tool, but I can't get the idle any lower. The idle screw is completely backed out on the front carb. The choke and linkage is disconnected. The AFR gauge is in the 12s at 1050, so it's not a lean condition. I put a vaccum gauge on the intake, and its pulling 18 which is in spec I believe, so I don't think I have any major vaccum leaks at this point. My timing is 10 degrees advanced. On start up it idles nice at 850 but as soon as she warms up and fuel is burning more efficiently, the idles goes to 1050. I suspect the issue is the front carb. I took the front carb off to see if the throttle plates are closing all the way. They look closed, but if you hold the carb up to the light, you can see a ring of light on the bottom half of the plates. I don't know if this little bit of air is enough to cause the idle issue. I will check for lose throttle bearing again, with some carb cleaner but I couldn't find the problem the first time around. I don't know where to go from here.

Mystery is solved. I thought for sure it was the horn relay, but it wasn't. The problem was the connection for the horn in the steering wheel. Many moons ago when the car was being prepped for an ITS track car, I put a Sparco steering wheel on and apparently left the horn connection just dangling inside. Sure enough this was the cause of the drain. Steve, thank you so much for your help. You were a big help, especially when you kept asking me if I knew how to use an ammeter lol.

Well, it's the circuit the horn is on. It is drawing .5 amps. However, I have no horn installed at the moment.

I can say how long exactly it took for the battery to drain. I do know it drained over the course of a week. I do understand the basic concept of how to use an ammeter, voltmeter, test light etc and I do have a multimeter, although I don't have much experience.

Am I correct in assuming my battery drain is due to that circuit seeing power all the time? I don't suppose the problem could be in the combo switch since the other two circuits are unaffected? Looking at your list: I don't have a voltage regulator. It is internal to my new alternator. I don't have a stereo or radio. I don't have any aftermarket accessories.

I think I was misreading the ignition switch and it is functioning correctly. I used a voltmeter to check the fuse circuits and everything is as you described EXCEPT the third fuse from the top on the right (Park, Tail) gets 14v all the time, even with the combo switch off. Now what lol...

Ok, for the circuits in green, does the key have to be in the ON position AND the combo switch on? Will they power with the key in the off position and the combo switch on?

Steve thank you for this info! My ignition switch will not move in the off position. Using a voltmeter, I verified that I am indeed getting power to all of the circuits you circled in green. The car starts no problem. I got it started for the first time in 16 years last week. I didn't realize the situation with the ignition switch until today when my one week old battery was dead.

My ignition switch will only go in the on and start position. Of course this led to a new dead battery. I was wondering which fuse box circuits should see power ONLY when they key is in the on position?

Thanks, got it. Is it really necessary to take this spot down to bare metal? I just painted the engine compartment lol 😒

What is this ground coming from in the picture below? Is this coming from the starter or from the alternator, or something else?

I had the radiator boiled out. I also flushed the engine when it was out of the car. Changed expansion plugs, new water pump, thermostat, hoses.

I'm not having cooling problems. I'm getting ready for first start up in decades. I was just wondering with today's options, what type of coolant is being used in classic cars like the Z.

What are you guys using for coolant these days? The water less coolant seems interesting, but there are drawbacks. Mainly, if you have an issue while on the road, you're kinda screwed because it doesn't play well with water. It is also a bit more expensive. I am running my stock radiator, so there is a mixture of all types of metals going on.

Thanks Captain!

The video only shows him using one round gasket for the damper.

It looks like most SU rebuild kits come with two gaskets, needle valve, hose, and 6-7 round washers/gaskets of various sizes. Exactly where are those 6 round washers used?

What about the need for the condenser by the coil? Should that be eliminated with the Petronix unit? Does it serve a dual purpose, one being to eliminate unwanted radio frequencies for the radio, etc?

Ok, great. I was hoping this was the case. Thanks!

Is it normal for the oil slinger to slide past the woodruff key, or should the key engage the slinger? It slides past the key here.

You asked if I changed the clutch recently and that there may be an issue with the pressure plate. My car is in a rebuild state and the engine has not been in the car since I changed the slave cylinder.

This is what I mean by the rod is still making contact. The nut is screwed all the way down, but there is no free play with the lever as suggested. Also, the rod will push into the slave cylinder with about 20mm of travel. Please keep in mind that the engine is not in the car at this time, so that eliminates any issues with clutch, etc. When I push the rod into the cylinder, it does push back out as described by Zed. So, is this thing self-adjusting and has the adjustable rod?