InfiniteRPM

Hey guys I am fairly new with these cars.

I am working on restoring my '72 240z and it won't turn over. I tested the starter and it works fine. When I put the key in all I get is the choke light coming on. I am assuming the wiring is screwy somewhere but I really have no idea where to start.

Where should I be looking? When the key is in the "on" position, should I be seeing more lights? I can't even put the headlights or anything on.

I get a click from the starter when i try to turn it over. I had pulled the starter out, hooked it up to a battery and jumped the solenoid and everything worked properly. I tried jumping the solenoid with the starter on the car and it just clicks. So I'm guessing the starter is screwed, is there any way to test that?

Thanks in advance

Steve260Z74

First, download a copy of the FSM from XenonS30.
Next, check your http://en.wikipedia.org/wiki/Fusible_link. It's the wire coming off of your starter. If it is bad, you need to replace it with another fusible link. Do not use regular wire.

Also, how old is your battery? Check the voltage with a voltmeter while someone is cranking the starter. A bad battery can have 12+ VDC while not under load and drop to zero with load.

beg3yrs

Sure sounds like a weak battery or bad battery connections.

Headlights, which draw a lot of current, won't come on but the choke light, which is a minimal draw, will.

With the key in the on position, your turn signals should work, radio should work and of course if your choke is on, that light should come on as well. Your dome light should always work.

The click you hear is the starter's solenoid which is a low current draw device. The solenoid, when enabled, connects the high current battery lines direct from the battery to the starter motor. If you tested the starter separately and it's good, but won't turn over when installed and connected to the battery, that's another indication you've got a bad battery.

My old F350 truck wouldn't start the other day. Everything was dead. Turns out the battery terminals were corroded. All they need was a good cleaning and everything works great.

Clean your battery posts and connectors first. That's a lot cheaper than a new battery.

InfiniteRPM

Thanks for the replies guys. Now the battery is on it's way out the door. I load tested it and it is not the greatest but today I bought new connectors for the battery since they looked shitty. Turned the key a few times and only get clicking. Kept trying and it turned over. Had the car turning over for about 20 seconds and didn't get it to fire. I'm guessing I've got another issue if it has enough power to crank over but I get nothing else. I was told this car was running last year (obviously can't take the guys word for it though).


So, I think I may still have a weak starter but I will replace the battery before I make that assumption. But I still think something is screwey with the wiring if it will crank over and nothing else works. The radio doesn't work. Dash lights don't work. Turn signals and headlights don't work.

beg3yrs, thanks for chiming in on all my posts so far you have already been very helpful.

Steve 260z74 - It could also be the fusable link. It looks pretty crappy so I will get one on order regardless.

Thanks again guys

After the failed start attempt I get no clicking when I turn the key. This is okay. I will wait for the battery to charge back up. Most likely buying a new one tomorrow if I find the time. Edit - waited for the battery to charge and had it cranking over again for approx 20 seconds.

Steve260Z74

You can get a new fusible link from Banzai Motorworks (Banzai Motorworks) or Motorsport Auto (Motorsport! Fusible Link, 71-73 240Z - The Z Store! Nissan-Datsun 240Z-260Z-280Z-280ZX-300ZX(Z31/Z32)-350Z-370Z Parts). Banzai is pretty much a one-man shop, and he doesn't take credit cards. I wouldn't hesitate to go with him. He might be out for the holidays, though. Call first, but he is responsive to emails.

beg3yrs

Sure looks like your first problem is a weak battery.

I'm going through a complete restoration on my Z right now. The car is 90% disassembled with the rolling shell over at a body shop. Here at the homestead I'm currently going through all my electrical. I've got the dash on a bench and all the harnesses spread out on the shop floor with everything I can plug in, plugged in. I was using a +12V power supply which would only deliver 6 amps. That was good for console lights and maybe the markers and turn signals but not much else. I went and got a new battery myself and now I've eliminated anything that could be attributed to a weak battery. I can help you pretty easily with electrical gremlins right now as I'm right in the middle of them myself. See the photo, it's sort of amusing!

You have mentioned you're concerned about the wiring. Why? Has some ******** pervious (appropriate spelling error I think ) owner been messing with the harnesses? I had that issue as well and it's another reason why my own test setup has been valuable although frustrating at times. Once I got the battery in, I'd check those light issues first. The ignition +12V comes off the assembly on the steering column. It is required for your turn signals and hazard lights. If you've got those working you should have the voltage going to your ignition control module, coil and all that good stuff. and you can get on with trying to start the motor.

I've gleaned a couple of other hints from your posts. First, you never saw this car run and second, it hasn't run for at least a year.

So, thinking ahead for the time when your battery is known to be good (BTW, keep your charger handy) and you've sorted your light issues you can move on to starting the motor. You will have some issues common to cars that have been sitting for a while. Remember the three basic needs for getting your engine to run: Air, fuel and fire.

Air: Many folk think that just means your air filter is clean but ... if your carbs aren't opening right or they're dirty, that could be an issue. Also, if you've got a big vacuum leak, that could keep your engine from sucking air and fuel in. Check for missing lines (open ports with nothing attached is a big clue), cracked lines and so on. Replace as required. Depending on what they are you can just temporarily plug them, just remember to address that issue later.

Fuel: For long time "sitters" IMHO this is a very common issue. Bad gas, clogged fuel lines and fuel pumps, stuck carb floats and so on. I'd open up the float bowls, clean them out, make sure the floats move freely and check the levels. It isn't hard to see if fuel is getting in there either. Simply pull the fuel lines at the carb (one should do) and place it into something to catch any fuel (like an empty beer, er milk bottle). Crank the motor for a while and see if fuel is flowing. If it is, let if flow to flush out the lines. If not you've got to start tracing back. BTW, before you do this, is there gas in the tank? If it's old, drain it and put a gallon or two of fresh stuff in there. Be sure to disconnect your spark coil as with fuel flowing around, you don't need any extra sources of ignition. I keep a fire extinguisher in the garage to ward of bad juju.

Fire: That's your spark. You can test spark pretty easily, there are lots of ways. Some folk pull a plug and let it rest on the block so it has a ground and then crank the motor. You can visually see if you've got spark. You should also check your distributor cap to see if its worn. Not very expensive to replace it and the rotor. Are your plug wires worn, cracked or broken? You know what to do if they are.

Well, that's enough for now. Hopefully this will help and also get some other more seasoned mechanics here on the forum to chime in as well.

Let's see how you get on with this! Best of luck, keep us posted. Your experiences will help us too.

Steve260Z74

From the other circuits the OP mentioned that aren't working, the fusible link is a likely suspect. If it's bad, he won't get the car running.

beg3yrs

Well you might be right but ... OP mentioned in his very first post that his choke light did come on so I figured the fusible link is OK. The choke light is powered from the +12V through the ignition lead on the key switch. That lead gets its +12V via the fusible link ...

Also, OP is now able to crank the motor. The starter relay also gets its +12V via the fusible link. Again, more evidence in my mind the fusible links are OK.

Given that I do have a track record of going down rabbit holes ... InfiniteRPM, you can test your fusible links. If you've got a multimeter, pull the links and check them for zero (or really really close to zero) resistance. Generally they'll be zero if good or infinitely high when bad. It could be a case where there's something higher than zero and anything more then a couple of ohms I'd say they're bad as any unnecessary resistance in a low voltage circuit is bad.

Make you sure you know your meter is good by simply touching the two test leads together when it is in resistance mode. If your meter can't be "zeroed" (my Harbor Freight cheapie can't) then the reading you get is effectively zero.

One other thing, be sure to go through your fuse box. Make sure all the fuses are good, they are the correct amperage (a few of mine were not) and make sure your contacts are clean. The fuse box is yet another source of unnecessary resistance (and BTW, smoke in the cabin).

Steve260Z74

He only has one fusible link unless someone modified his car.

beg3yrs

Here I go getting my 260s and 240s mixed up again.

I hope InfiniteRPM gets things going soon ...

InfiniteRPM

Hey guys just to update, Fuel is fresh, new battery is installed. Headlights, tail lights, turn signals etc. are working.

Problem now is the car will only turn over slowly or just click. I have the battery charged up. Seems like the starter isn't working properly


The plugs and wires on the car look like they have been replaced in the last year. The reason I was worried about wiring is because I found a few mouse nests in the car while tearing it down but it seems whey were just chewing on the sound deadening in the floor. Also the steering column was pulled apart. A new key was made for it by the previous owner so I don't know if that has to do with the steering column being apart.

Making slow progress as I have a lot of other jobs I am working on right now as well. Here she sits.

Thanks for the help so far

zxguy1986

I have to give you 20 points just for taking on a project this size. Not many of us could do it... Congratulations and (so far) well done Please keep us up to date on it. Amazing.

Also, gotta love that work space you got there! You are privileged!

InfiniteRPM

Thanks a lot. This is going to be a huge experience for me. I'm 21 years old and the most I have done in the past was buy a couple of crashed snowmobiles and fixed and resold them for some profit. Worked a couple of years in an auto shop and I'm hoping that experience will help me along. I now work as a warehouse manager and customer service coordinator. Lucky enough that the boss is giving me a corner to work on the car.

I'm hoping it's ready sometime in the spring but I'm not sure if that's realistic haha.

beg3yrs

Congratulations on the progress, that's great! I too am jealous of the space you've got available. Keep it up.

OK, starter, hmmm ..... Since you've already made sure your positive cable from the battery is going direct to the starter, the negative cable is connected to the block/tranny/starter mounting, the connections are clean and good and you've got a new and charged battery, I think you're right to be suspicious of the starter.

Since you can hear a click, you might have a dirty solenoid connection. If you have the gumption, take it apart and give it a good cleaning. Failing that, many auto parts stores will test them for free. I know my local O'Reilly Auto Parts does it (they'll do alternators too). Rebuilt ones aren't that expensive either.

BTW, you're thinking Spring. I was too, but I was wrong about which year ...

Pez

I had a significant coolant leak where the heater hoses exit the cabin through the bulkhead. This had apparently been happening for some time and the PO had not addressed it.

Anyway, the location of those two hoses is right over the starter, and the soaking was too much for it. It would start very slowly, unless the battery was completely charged.

I fixed the leak, replaced the starter and all was good.

InfiniteRPM

Pez, that seems to be exactly what the car is doing. If I leave the car on a trickle charger for the night, it will turn over great for a few seconds but if I let off, it will either turn over slowly or just click.

I'll pull the starter again and see if cleaning anything in there makes a difference. Starters for this car aren't nearly as expensive as I expected. Also have a fuel leak when cranking over that I will have to get fixed first (at least it's pumping fuel? haha)

Just want this beast running before I start getting too far into it.

InfiniteRPM

Hey Guys!

Found a local guy who was selling a used starter for a 240. Cranks over great now! Got the fuel leaks fixed. But it seems my fuel pump isn't working. I will pull the pump and see if it works and check the relay. Hopefully getting close to getting this thing to start.


Thanks!

InfiniteRPM

Okay now I'm really confused. My electric fuel pump isn't working. In researching I am trying to find out where the relay is. I am finding so many different answers. Some say there is a fuel pump relay and some say there isn't. Is there a relay? If so where is it? I want to test the pump and the relay.

Steve260Z74

The stock configuration for a 1972 North American 240Z is to have a mechanical fuel pump mounted on the head at the front of the engine. Is that fuel pump present?

While there is wiring for an electrical fuel pump, that was not a stock configuration. Be sure to download a copy of the FSM so you can see the wiring diagram. It is a green wire coming off an inline fuse. The wire on the other side is black/white, coming from the ignition switch. The fuse should be hiding somewhere around the center stack.

InfiniteRPM

Okay I am taking a look through the manual. There is still the stock manual pump.

Edit- Well now I feel like a complete idiot. My fuel tank is dryer than a popcorn fart. I forgot to put fuel in it. I guess I should do that before trying to pump gas through the lines.

Steve260Z74

Make sure your fuel lines aren't cracked, either. If the rubber lines are cracked between the fuel tank and the fuel pump, the pump just pulls air. And you may want to consider a new fuel filter while you're at it.

InfiniteRPM

Thanks! I actually just replaced the rubber lines tonight before filling it up with gas. I will be ordering a new filter, the tune up kit and a lot of other parts from MSA.

I pulled the fuel lines off the carbs and turned the engine over, I had gas pumping.

I just want to get as many problems figured out as I can before I order parts so I don't have to pay for shipping on multiple orders.


My clutch goes to the floor when I press it and the reservoir was low. I tried bleeding it with the shop manual's instructions and I couldn't get a drop to bleed. Can I blow compressed air through the reservoir with a blow gun and a rag? Or is there a valve/seal I would be damaging?

InfiniteRPM

The master cylinder is shot.

Spent my day yesterday working on the car. Pulled the carbs apart and cleaned them out. It will spit and sputter when I try to start it. It is so close to running. I'll check timing tonight and put the new distributor cap, points etc in the car. Hopefully it gets running after that. If it doesn't start after that I'll be leaning towards a carburetor problem.

beg3yrs

Boy do I hear you. If it isn't one thing, it is another. But hey! Your motor is spitting and sputtering. That's wonderful. I can't wait until I get to that point with my project.

So, your master cylinder is shot. They can be had new for around $45 or less. Rockauto.com has at least four different ones (of course none are Nissan OEM) right now and they've got a 5% discount going until March 11. Enter SS25115 in the "How did you hear about us?" box when you check out (no, I'm not a shill for Rock Auto - just trying to help).

I got a new master cylinder at PartsGeek.com back in June. Transaction was OK but they don't communicate much. Basically took my credit card and I didn't hear from them - I did get the part though and it is just fine.

If you do get another one, be sure to bench bleed it before you install it in the car. If you don't know how to do that, check out youtube. There are multiple videos that will show you how to do that.

InfiniteRPM

Thanks for the input, I didn't know about bench bleeding - will be sure to do that!

I have put new points, condenser, distributor cap, rotor, and plugs in the car (points and plugs are gapped). Had it running! It takes a few seconds to get it going and I have to play with the choke to keep it running. Once it starts to warm up it seems to run fine but still needs some choke. I have done a compression test, fuel is pumping, and there is fresh gas.

Prior to this car, I did a lot of work on snowmobiles etc. The problem is, I don't know a lot about this style of carburetor. It doesn't make sense to me. So I just cleaned them and put them back together the same way. I figure this is a carb problem but I don't know where to go from here.