ericbauer Posted September 27, 2013 Share Posted September 27, 2013 Hi guys I got everything back together on the car. Mechanically everything checks out and I'm real happy with it. However I must admit that I am electrically challenged. Can someone please help me with a step - by - step of how and what to check? It's probably something hopelessly obvious but like I said I've never been good with engine electrical... Car has a MSD7AL2 Car was running before engine rebuild Out of curiosity I sent the MSD7AL2 to MSD while the engine was in pieces and they said it was A-Ok - nothing wrong with it Before engine rebuild car had a MSD Pro Power Coil that had a loose connection I replaced it before the engine rebuild with a Pro Power HVC Coil - car ran great with new coil Distributor is an electronic Nissan distributor from an 80s model car - no points MSD7AL2 connections are relatively simple +12V to the battery - I've checked there is battery voltage at the MSD7AL2 ground - checked that too an orange wire that goes to coil positive a black wire that goes to coil negative a wire that goes to switched ignition green and blue wires that go to distributor The wiring connections / colors are printed on the MSD7AL2 box so all these wires are in the right place Battery has voltage Starter spins the engine No spark I've pulled plugs, put one plug in the longest spark plug wire, balanced it on the shock tower bolt, no visible spark as I am cranking the engine Before I start pulling out this ignition and put in the one from the other car, what can i check? Thanks for your help guys! -e Quote Link to comment Share on other sites More sharing options...
ericbauer Posted September 27, 2013 Author Share Posted September 27, 2013 I should add that mechanically I am certain that distributor driveshaft is right at cyl #1 on compression stroke absolutely positive about that... Let me also ask a different question if you don't mind... I'm thinking about just swapping in the ignition from my other Datsun onto this car. The ignition on the other car is aftermarket, it has its own distributor and ignition control module, it works with any coil. There's a simple plug from the distributor to the ignition control module, and there's two wires from the ignition control module that go to the coil (+ and -) If I just swap all those over, do I need any other stock wiring going to the coil for the car to work? I know I would need a wire coming off of coil neg to act as a signal for the tach, but i can drive without a tach if i have to is there anything else required to just get the engine running? Quote Link to comment Share on other sites More sharing options...
roye@hrewheels.com Posted September 30, 2013 Share Posted September 30, 2013 Try tying your switched ignition +12 to the battery for the purpose of a test fire. I had a similar issue with my 6AL, I had it all connected "properly" but could not fire off. After adding a simple toggle switch for my ignition hot I had no problem. What I eventually found was that the factory ignition switch had a dead spot if I turned the cylinder to far, the starter motor would run but the ignition hot would go dead. Quote Link to comment Share on other sites More sharing options...
Lazeum Posted October 1, 2013 Share Posted October 1, 2013 (edited) Have you checked every single component? If you have no spark, you need to think about what could be wrong in your system and test them all. You need to start a proper problem solving activity So instead of providing you answers, I'm going to provide you many questions you need to answer. Other questions would then follow You should try those tests with ignition key set on "on" & "start", one of the circuit might be broken/opened. Disconnect the starter solenoid for those tests to avoid engine to crank. Most of them only require a voltmeter & an Ohmmeter. It should be easy. If you have no spark, something is not working, so I list all the items that could go wrong: battery, fuses, coils, dizzy, MSD box, ignition switch, harness, spark plugs, spark plugs wires. Battery: Does it have at least 12V between terminals? Fuses: are all fuses ok? check especially fuse for ignition since this is your problem. Coils: Do you have power? Is the coil ok? How are the resistance between terminals? Is the ground for coils ok? Dizzy: have you checked if it works properly. I've never messed around with Datsun ignition but on my previous seup with Mallory Unilite dizzy, I could have taken something to cut the beam & create a spark. With a voltmeter, it is just a matter of controlling that voltage at coil was getting low (=short) MSD box: what does the manual says? MSD said box is ok so focus only on connections on your car: does the box receive power? Is ground ok? Ignition switch: Do you see power at the coil going from 0V to 12V when operating the switch? check it at every ign. switch position. If you still have the ballast resistor, you should only read around 9V at coil on "start" position. Harness: if previous test are ok, if should be good. spark plugs: do you they look ok? a visual inspection should tell you if they would work or not. If you're hesitant of if it was fouled previously, try a new one for test. Spark plug cables: check their resistance, you should read read something other than 0 Ohm to make sure they're ok. If you have a "no" answer poping out, you should ask yourself why it does not work and find out why. I hope that helps. Good luck! Edited October 1, 2013 by Lazeum Quote Link to comment Share on other sites More sharing options...
ericbauer Posted October 1, 2013 Author Share Posted October 1, 2013 (edited) So here's where I am at: Original ignition that came with the car (and had been running prior to engine rebuild) is: Nissan p/n 22100-p8003 (80s R30 Skyline L20 Turbo) distributor that had been modded by prior owner with an optical trigger (three wires: switched power & two signal wires hooked up to green & purple signal wires on MSD7AL2) (It uses the same cap and rotor as 280ZX Turbo) MSD7AL2 - recently tested and cleared by MSD as fully functional HVC Pro Power coil specifically for MSD 7 boxes - I bought this new about a year ago I have constant 12V at the MSD box I have switched 12V at the MSD box when I turn the ignition key to the right point I have continuity between the MSD box and the coil + and coil - wires I have some voltage coming out of the blue and green wire connections at the MSD box (7.xV and 9.xV) I have switched 12V at the corresponding wire coming off the distributor the ground wires at the block (one on front cover below distributor, one on head by cyl 1 sparkplug) are nice and tight the neg wire off the battery is securely grounded to the sheetmetal The plugs are new The plug wires check out just fine When starting the car the engine turns freely, there is gas, but no spark When starting the car there is no voltage at the coil When I swap everything out to the alternate ignition from my track car (kameari distributor, new MSD coil, same plugs, same plug wires) - it fires I've tried swapping coils and it did not make a difference on the original ignition, still no spark. I'm guessing it has to be the distributor on the original ignition? Do you concur? Edited October 1, 2013 by ericbauer Quote Link to comment Share on other sites More sharing options...
Lazeum Posted October 1, 2013 Share Posted October 1, 2013 (edited) The MSD might not provide some voltage to your coil, it might be normal. For your dizzy, if you block the lazer beam with something; a credit card might be not opaque enough (I mean: non transparent - I'm not sure about my English here ), you should experience some drop in voltage on your dizzy terminals. Anyway, your issue looks like the one I had last year. I had no power at coil, everything else was normal. So I remove the Mallory box (6AL) from my setup to test, car run perfect without it. Mallory box teardown showed some major issues (overheating - it happened after 300mi run - 50 yds before being home ) On your side, it might be interesting to remove the box from the equation and see if it runs without it, or at least if you got spark this way. It was an 1h operation on my side. I don't know the specifics of your 7AL box, it might be not so easy to do but it could be worth it to give it a try. Edited October 1, 2013 by Lazeum Quote Link to comment Share on other sites More sharing options...
NewZed Posted October 1, 2013 Share Posted October 1, 2013 (edited) When starting the car there is no voltage at the coil This might provide some insight on the issue above - http://www.msdignition.com/page.aspx?id=15713 The instructions might help also. There's a troubleshooting section included, testing for spark, etc. You have to use part number 7222, it doesn't recognize 7AL2 (goofy!) - http://www.msdignition.com/instructiondownload.aspx Apparently MSD has filed bankruptcy so it wouldn't be surprising to me (natural born cynic) if they were just returning everything as "in-spec." until the company dies. No guarantees that your unit is actually good. Edited October 1, 2013 by NewZed Quote Link to comment Share on other sites More sharing options...
Lazeum Posted October 1, 2013 Share Posted October 1, 2013 Apparently MSD has filed bankruptcy so it wouldn't be surprising to me (natural born cynic) if they were just returning everything as "in-spec." until the company dies. No guarantees that your unit is actually good. I second that! Another link to make some test of the box: http://www.msdignition.com/page.aspx?id=3206 Quote Link to comment Share on other sites More sharing options...
ericbauer Posted October 3, 2013 Author Share Posted October 3, 2013 I've got spark ! Well at the coil at least... I had forgotten you could test an MSD unit for spark the way it's described in the instructions Matt sent above Unplugged distributor, shorted green and purple wires together, touched the coil lead to ground = big meaty spark ! So it is the distributor after all, as I initially thought... bummer... getting a '80 ZX with the E12-80 module now. -e Quote Link to comment Share on other sites More sharing options...
Lazeum Posted October 3, 2013 Share Posted October 3, 2013 Good stuff! At least you know what's wrong. You're on the good path to solve for good your issue. Quote Link to comment Share on other sites More sharing options...
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