the240z Posted February 29, 2016 Share Posted February 29, 2016 (edited) Hi, Just picked up a 72 240z. Put some new fuel in it, it gets up to the carbs just fine. new battery, and i cannot get it to start. A few things that I have noticed that might be relevant are as follows: When I turn the key to ON just before start, the tach rolls all the way to 9000 and just sits there even when attempting to start. I pulled the coil wire off the distributor and and held it to the intake and it sparks great for a few sparks then it won't spark for a couple of turn overs then it will spark a couple good times then it won't. I am guessing this is related to it not starting. I am lost at what to do, any ideas? Thanks EDIT: PICS ARE HERE http://imgur.com/a/oEu1V Edited March 1, 2016 by the240z Quote Link to comment Share on other sites More sharing options...
NewZed Posted February 29, 2016 Share Posted February 29, 2016 Remove the distributor cap, take a picture of what's under it, and post it here. Quote Link to comment Share on other sites More sharing options...
the240z Posted February 29, 2016 Author Share Posted February 29, 2016 ok ill post a bunch of pics of stuff too incase you see something that is wrong Quote Link to comment Share on other sites More sharing options...
seattlejester Posted February 29, 2016 Share Posted February 29, 2016 Did it ever start? I would be concerned about compression if some of the other things start to check out. I say get an inline spark tester as well. $5, no more guessing if the spark is firing or not. Some pictures would be nice, especially of the ballast resistor and the coil on top of the rotor, cap, and spark order. Quote Link to comment Share on other sites More sharing options...
the240z Posted February 29, 2016 Author Share Posted February 29, 2016 My understanding is that it has been years since it has started. BUT If I go to start it, it will pick up and get really close to starting or run for a brief second then just keep turning over. Then if I try again all it does is just roll over without starting or picking up. IF I let it sit for a while it will almost start up again but no success. PICS COMING VERY SHORTLY Quote Link to comment Share on other sites More sharing options...
the240z Posted February 29, 2016 Author Share Posted February 29, 2016 (edited) PICS http://imgur.com/a/oEu1V Edited February 29, 2016 by the240z Quote Link to comment Share on other sites More sharing options...
seattlejester Posted March 1, 2016 Share Posted March 1, 2016 Hmm how are you verifying gas getting to the carb? I would be tempted to use starter fluid to take that out of the equation. Timing would be another question. Check that the engine is at TDC, when you open the oil fill cap you should be able to see the two cam lobes up in bunny ears, the rotor should also be pointing at cylinder number 1. If all that criteria is true, then throw on a timing light, that would also point towards if you are getting a consistent spark signal rather then grounding out coil. Quote Link to comment Share on other sites More sharing options...
the240z Posted March 1, 2016 Author Share Posted March 1, 2016 I drained the little plug at the bottom of the both carbs and turned it over a little and more fuel came out so its at least getting to the carbs, I've tried even just running it on starter fluid to no avail. I am not sure about the distributor whether it is stock or not, but the cap says BOSCH on it and I think the little lump on the side of the cap means 1 but it isn't aiming towards the #1 cylinder Quote Link to comment Share on other sites More sharing options...
NewZed Posted March 1, 2016 Share Posted March 1, 2016 I just wanted to see if he had points. This is just basic engine stuff. The tach problem looks like just a bad tach, probably not related to not starting (weird that a double negative works there...). Try starting fluid. Then go to the Engine Tuneup chapter of the FSM. http://www.nicoclub.com/FSM/240z/ Quote Link to comment Share on other sites More sharing options...
NewZed Posted March 1, 2016 Share Posted March 1, 2016 I've tried even just running it on starter fluid to no avail. But did it start, then not run, or not start and not run? Communication is paramount. Quote Link to comment Share on other sites More sharing options...
the240z Posted March 1, 2016 Author Share Posted March 1, 2016 http://imgur.com/a/QhXmm I OK I think my cap might be on backwards, the lump is facing towards the firewall Quote Link to comment Share on other sites More sharing options...
the240z Posted March 1, 2016 Author Share Posted March 1, 2016 But did it start, then not run, or not start and not run? Communication is paramount. Wouldn't even start. Sorry for the illiteracy. I have been trying to figure this out all day. Quote Link to comment Share on other sites More sharing options...
NewZed Posted March 1, 2016 Share Posted March 1, 2016 Get a meter and and measure coil voltage with the key on. Positive terminal to ground and negative terminal to ground. Compare to battery voltage. Check the condenser, it might be shorting. Points are pretty easy to play with because you can see them, and move them by hand. You can crank the engine and watch them open and close or remove the distributor and rotate it by hand. Focus on the basics of a points ignition system. Quote Link to comment Share on other sites More sharing options...
seattlejester Posted March 1, 2016 Share Posted March 1, 2016 Hmm, yea kind of depends on how far we want to go back. Make sure the distributor is getting power with key on, and cranking, multimeter will be the key here. Values for voltage would also be nice. Also checking the general timing will be important. You mentioned that the engine tries to start, does that mean it is catching a little bit? Or just spinning very fast? Going through what I wrote down will be useful for getting in the ball park. Set crank to Top Dead Center using the indicator near the crank pulley. Check the cam through the oil cap. If you can see both lobes up, then you are on the right rotation. If the lobes are pointed down, rotate the crank a full 360. Once the cam is verified, then pull the distributor cap and verify the rotor is pointing towards the wire that leads to spark plug 1. If it is not, then you might be 180* out or the spark plug order may be off. If it is out, correct it. Either by flipping the cap, or reordering the plug wires. Another thing to check is the spark plugs themselves. Are they new? Are they gapped? Also when you sprayed with starter fluid did you make sure to lift the pistons? Or else you are just spraying a cylinder and most of it will not get near the intake tract. To check if gas is getting to the carbs, pull the return line off the fuel rail and run another line to a remote reservoir to check that you are getting fluid. I say remote because this will be pumping gas, make sure it is away from the ignition sources. Quote Link to comment Share on other sites More sharing options...
the240z Posted March 1, 2016 Author Share Posted March 1, 2016 Hmm, yea kind of depends on how far we want to go back. Make sure the distributor is getting power with key on, and cranking, multimeter will be the key here. Values for voltage would also be nice. Also checking the general timing will be important. You mentioned that the engine tries to start, does that mean it is catching a little bit? Or just spinning very fast? Going through what I wrote down will be useful for getting in the ball park. Set crank to Top Dead Center using the indicator near the crank pulley. Check the cam through the oil cap. If you can see both lobes up, then you are on the right rotation. If the lobes are pointed down, rotate the crank a full 360. Once the cam is verified, then pull the distributor cap and verify the rotor is pointing towards the wire that leads to spark plug 1. If it is not, then you might be 180* out or the spark plug order may be off. If it is out, correct it. Either by flipping the cap, or reordering the plug wires. Another thing to check is the spark plugs themselves. Are they new? Are they gapped? Also when you sprayed with starter fluid did you make sure to lift the pistons? Or else you are just spraying a cylinder and most of it will not get near the intake tract. To check if gas is getting to the carbs, pull the return line off the fuel rail and run another line to a remote reservoir to check that you are getting fluid. I say remote because this will be pumping gas, make sure it is away from the ignition sources. When it does go to try and start it catches real nice like its SO close to starting, hard to describe that sound, but then it just goes back to turning over and might catch one or two more times and then nothing. I tested the ohms of the ballast resistor and it was 1.5 i think? also tested the coil and it was 12v. I just got 6 new plugs an hour ago. Quote Link to comment Share on other sites More sharing options...
NewZed Posted March 1, 2016 Share Posted March 1, 2016 When it does go to try and start it catches real nice like its SO close to starting, hard to describe that sound, but then it just goes back to turning over and might catch one or two more times and then nothing. I tested the ohms of the ballast resistor and it was 1.5 i think? also tested the coil and it was 12v. I just got 6 new plugs an hour ago. Where are you spraying the starting fluid? I think that you need to lift the pistons with SU's to get anything past them. Can't emphasize enough that the details matter. "tested the coil and it was 12v" doesn't mean much of anything. Quote Link to comment Share on other sites More sharing options...
the240z Posted March 1, 2016 Author Share Posted March 1, 2016 Where are you spraying the starting fluid? I think that you need to lift the pistons with SU's to get anything past them. Can't emphasize enough that the details matter. "tested the coil and it was 12v" doesn't mean much of anything. I took the air filter box off and sprayed into both the carbs to try and get it to start. I FORGOT TO MENTION CAUSE IM AN IDIOT BUT!!! The Previous owner told me there was a fire under the hood a long time ago. the only wires burned were one that goes to the back of the distributor and the one that goes to the TEMP sending unit. I have no Idea what the wire that goes to the back of the distributor is but i replaced it. Quote Link to comment Share on other sites More sharing options...
seattlejester Posted March 1, 2016 Share Posted March 1, 2016 I'm not too familiar with points, so I can't recall what that wire does. If it is that close to catching I must reiterate what Newzed and I have mentioned above, are you lifting the pistons in the carb? If you just spray the carb you are spraying at a very very small orifice or more likely the side of the cylinder in the carb, that fuel will be used almost immediately. Have someone crank the motor and lift up the pistons and scary a liberal amount into each and see if it catches. Additionally and especially if you have messed with the spark plugs, check the firing order from the distributor cap. If that is out of order it will try to catch once in a while and basically stall itself out almost immediately. Also need a confirmation on the timing. Did you confirm the cylinder is on the compression stroke at TDC with the rotor pointing at 1? Quote Link to comment Share on other sites More sharing options...
the240z Posted March 1, 2016 Author Share Posted March 1, 2016 Firing order is 153624. And when 1 is TDC it aims right at 1. I didn't lift the pistons in the carburetors I will try that in the morning....I'm hoping I didn't get shafted on this deal LOL... this is my second 240z first one had a v8 in it so never had these issues, is there anyone to ask about the value of the car verse what I paid for it? Quote Link to comment Share on other sites More sharing options...
the240z Posted March 1, 2016 Author Share Posted March 1, 2016 I am hoping it's a fuel thing I will pull the carbs apart tomorrow if I can. Quote Link to comment Share on other sites More sharing options...
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