cd1105 Posted November 28, 2011 Share Posted November 28, 2011 (edited) I've been at this build for two years threw the ups and downs, but this one may be the down that breaks me. I'm an l28et swap in my late model 260z(11/74). For the past two months I've been trying to get the car to crank and fire, with no luck. I have fuel and spark(will get to the spark in a second) but the car won't fire. Originally i thought traced the problem to my battery(optima red top), it had sat for almost a year and when I went to put it in the car it didn't start. So I thought simple enough, I would charge the battery. I charged the battery to full and it would crank, for a few times and then slowly die out. I had a friend give the battery a jump and I would get power, and then again crank and die out slowly like it was losing cranking power. I sent the battery, back for the warranty, and in the the time it took for them to send me a new battery I figured out I had a timing problem, where the oil pump shaft wasn't lined up correctly. I fixed the problem and aligned the shaft accordingly to the fsm(82 280zx). When the new battery arrived I had dropped it in turned the key and again tried to fire the car, but with no luck. I suspected that there was a problem with the connection from the ignition switch, to the wire that connects to the starter, so i by passed it and tried jumping the starter. When i jumped the starter the motor cranks over and slowly loses cranking power, but again fails to fire. Here's the twist, if I jump the starter and the motor cranks over for a few seconds I can hook up the ignition wire back up to the starter, go back in the car and crank it over with the key for a while before it starts to slowly die out and lose cranking power. I thought maybe I have a bad starter, so I went and picked one up from kragen tonight and tried to start it again both with the key(which didn't work) and jumping the starter. When jumping the starter the motor again, cranks over for a few seconds strongly but slowly loses power and the cranking becomes weak. I verified the timing on the distributor, and that the cylinders were getting fuel. The spark is weird, by that I mean when I use the key to turn the ignition to the "ON" position the ecu light, fuel pump comes on to prime the fuel system, and you can hear a spark tick at about 2 second intervals(I also pulled a spark plugged and watched it do it). I almost sure that I'm not supposed to be getting a spark like that when the ignition switch is only turned to the "ON" position, I believe it should only spark when I turn the switch to the start position. I have no idea what can be causing this. To add to all the madness, today i when I tried to start it by jumping the starter it started to crank and then all of a sudden it KEPT GOING even after i stopped jumping the starter. I rushed to turn the key to the off position and it kept going. Wires started to smoke in the engine bay and under the dash(f!*K) so i ran to the battery and disconnected the power wire and it stopped. On my car the battery is relocated to the hatch and the positive wire goes through a hole in the firewall directly to the starter stud, and the ground wire is hooked up to where the passenger seat belt bolt is on the body of the car. I haven't hooked up the battery again to see if everything thing was still working, lights, blower motor, headlights, etc... I', too scared to hook back up the battery to check everything, in fear that I might further damage the wiring. The only thing i can think of is something may be wrong with where I spliced my switched and 12v start connections for the F.I. harness that is drawing power. I have the yellow 12V wire from the F.I. harness spliced under the steering column into the stock 12v yellow and black wire, and the switch power wire(black/white) from the F.I. harness spliced into the stock black/white wire(ON) under the steering column. There is also a switched power wire coming from one of the relay in the engine bay spliced into another black/white wire i found in the stock harness in the engine bay. I've came so far to give up on this thing now, but I don't know what else to do, the continuous cranking and smoking wire really threw a curve-ball at me and I am low on LOST. I'm in need of some help from someone in the Bay area that has done this swap, for some guidance. If you can help please pm me your contact information, Thanks. I don't think I can solve this "series of unfortunate events" over the forums ..........would love to be proven wrong Edited November 29, 2011 by cd1105 Quote Link to comment Share on other sites More sharing options...
z-ya Posted November 28, 2011 Share Posted November 28, 2011 This is what I would try. Disconnect the main + cable and solenoid wire from the starter. Remove the battery from the car and connect it to the starter with jumper cables. Minus (-) to chassis, and plus (+) to the large terminal on the solenoid. Then make a short wire that you can intermittently connect between the solenoid spade connector and the + jumper cable (or battery +). This should isolate the car electrical from the starter. Touch the wire from the spade connector on the starter to the battery +. Pull the spark plugs out. The engine should turn freely for an extended period of time if the battery is fully charged (charge it before this test). If the engine slowly cranks and then dies, then you may have internal mechanical engine issues. Quote Link to comment Share on other sites More sharing options...
cd1105 Posted November 28, 2011 Author Share Posted November 28, 2011 (edited) This is what I would try. Disconnect the main + cable and solenoid wire from the starter. Remove the battery from the car and connect it to the starter with jumper cables. Minus (-) to chassis, and plus (+) to the large terminal on the solenoid. Then make a short wire that you can intermittently connect between the solenoid spade connector and the + jumper cable (or battery +). This should isolate the car electrical from the starter. Touch the wire from the spade connector on the starter to the battery +. Pull the spark plugs out. The engine should turn freely for an extended period of time if the battery is fully charged (charge it before this test). If the engine slowly cranks and then dies, then you may have internal mechanical engine issues. I tried doing all that minus taking out the spark plugs. I'm going to try it with the spark plugs out and see what happens. Any idea what could wrong with the spark? i went out today and also noticed that the wire that was burning in the engine bay was a black wire(ground) in the stock harness. I found a thread of a guy who is having almost exactly the same problem as me - My link...maybe I don't have enough ground because i relocated the battery and the battery negative cable is no longer connected to the starter?? Edited November 29, 2011 by cd1105 Quote Link to comment Share on other sites More sharing options...
Gollum Posted November 29, 2011 Share Posted November 29, 2011 What ARE you using for ground? I'm up in vacaville and extremely busy. If you can't find someone to help you send me a PM and I'll see if I can work something out. Quote Link to comment Share on other sites More sharing options...
cd1105 Posted November 29, 2011 Author Share Posted November 29, 2011 What ARE you using for ground? I'm up in vacaville and extremely busy. If you can't find someone to help you send me a PM and I'll see if I can work something out. Because the battery is relocated to the hatch, the negative terminal cable off the battery is grounded to the passenger seat belt bolt(i'm not using the passenger seat), instead of the usual bolt on the starter. Quote Link to comment Share on other sites More sharing options...
Gollum Posted November 29, 2011 Share Posted November 29, 2011 And how's the battery grounded to the chassis? Same bolt? If not I highly recommend it. The chassis in these 30+ year old cars aren't the greatest grounds as I'm battling this fact myself. Run a good sized cable directly from the battery to the starter for the negative and ground it where convenient to the chassis. Then run a separate ground buss from the battery for everything else. Overall I'm curious to see this car now. Not even using a passenger seat? 100% win in my book. I don't have a dash yet I didn't consider ditching the passenger seat. Quote Link to comment Share on other sites More sharing options...
cd1105 Posted November 29, 2011 Author Share Posted November 29, 2011 And how's the battery grounded to the chassis? Same bolt? If not I highly recommend it. The chassis in these 30+ year old cars aren't the greatest grounds as I'm battling this fact myself. Run a good sized cable directly from the battery to the starter for the negative and ground it where convenient to the chassis. Then run a separate ground buss from the battery for everything else. Overall I'm curious to see this car now. Not even using a passenger seat? 100% win in my book. I don't have a dash yet I didn't consider ditching the passenger seat. Currently only the negative cable from the battery runs to the seat belt bolt. Is this not a good spot for grounding the battery? If not I think i'm going to try what you said and run a negative cable from the battery in the hatch to the stock battery grounding spot on the stater bolt. And yes no passenger seat...they're overrated and useless in my book lol. I would have got a minivan if I wanted to haul people around. Quote Link to comment Share on other sites More sharing options...
Gollum Posted November 29, 2011 Share Posted November 29, 2011 That might very well not be a great grounding spot. There's a good reason you generally ground the battery directly to the starter bolt, with a secondary connection to the chassis. A starter can draw in excess of 250amps all by it's lonesome self. That's some serious draw. So when you connect the battery ground to one point midway through the chassis, and the starter at another spot, event several feet away, you're asking a LOT of current to flow through your chassis. Remember, grounds are just as important for completing a circuit as the positives. You can also just use some jumper cables temporarily to see if there's any difference. Quote Link to comment Share on other sites More sharing options...
cd1105 Posted November 29, 2011 Author Share Posted November 29, 2011 (edited) That might very well not be a great grounding spot. There's a good reason you generally ground the battery directly to the starter bolt, with a secondary connection to the chassis. A starter can draw in excess of 250amps all by it's lonesome self. That's some serious draw. So when you connect the battery ground to one point midway through the chassis, and the starter at another spot, event several feet away, you're asking a LOT of current to flow through your chassis. Remember, grounds are just as important for completing a circuit as the positives. You can also just use some jumper cables temporarily to see if there's any difference. I think i will try that tomorrow, Thank you. I going to try and trace the grounds that were burned up and see how much damage there is.....I hope all of the grounds on the stock harness under the dash isn't burnt to hell. Do you have any idea what could be going on with the coil spark in the first post? Edited November 29, 2011 by cd1105 Quote Link to comment Share on other sites More sharing options...
cd1105 Posted November 29, 2011 Author Share Posted November 29, 2011 This is what I would try. Disconnect the main + cable and solenoid wire from the starter. Remove the battery from the car and connect it to the starter with jumper cables. Minus (-) to chassis, and plus (+) to the large terminal on the solenoid. Then make a short wire that you can intermittently connect between the solenoid spade connector and the + jumper cable (or battery +). This should isolate the car electrical from the starter. Touch the wire from the spade connector on the starter to the battery +. Pull the spark plugs out. The engine should turn freely for an extended period of time if the battery is fully charged (charge it before this test). If the engine slowly cranks and then dies, then you may have internal mechanical engine issues. Tried this and yes, the engine cranks over with no issues. Quote Link to comment Share on other sites More sharing options...
z-ya Posted November 29, 2011 Share Posted November 29, 2011 So then per Gollum's suggestion, you have a grounding problem. Why did you relocate the battery? I suggest putting back in the engine compartment and running new cables directly to the starter. All this probably has something to due with your ignition problem. Let's fix one problem at a time. Quote Link to comment Share on other sites More sharing options...
cd1105 Posted November 29, 2011 Author Share Posted November 29, 2011 So then per Gollum's suggestion, you have a grounding problem. Why did you relocate the battery? I suggest putting back in the engine compartment and running new cables directly to the starter. All this probably has something to due with your ignition problem. Let's fix one problem at a time. I wanted to clean up the engine bay to have the least amount of clutter in there. I'm going to try moving the battery back to the engine bay and hooking up the negative terminal to the starter. Quote Link to comment Share on other sites More sharing options...
NewZed Posted November 30, 2011 Share Posted November 30, 2011 How is the block grounded? You should run a big ground strap from the block to the body, if you don't have one. The negative cable that used to run from the starter bolt to the negative terminal was the main ground path for the starter. That will give a path of positive post to starter to block to body to seat belt bolt to negative post. Quote Link to comment Share on other sites More sharing options...
Guest Dan Gleason Posted November 30, 2011 Share Posted November 30, 2011 (edited) Hi my name is Dan Gleason. I've done 2 turbo swaps successfully. First item, Did you install fusible links? The fusible links protect the wiring harness from overload. The links are 40 amp and 50 amp. These can be replaced by fuses. There is a green wire and a red or (brownish wire), both of these wires need fuses in line with them for amperage protection. The green wire uses a 40amp fuse. The brownish wire requiers a 50amp fuse. Since there are limited fuses available use a 40amp fuse on both lines. All the parts you need are available at Auto Zone or O'Reilys. You will be bying 2 40 amp fuses and 2 fuse holders. You will also need male and female spade connectors to attach to the red and brownish wire. Second item, you may have a short in the wiring harness. This part is time consuming testing for continuity from the harness to ground.Did this wiring harness come from a running 280zxt. If not I suspect the harness. You can contact me at gleason_d@sbcglobal.net Dan Gleason Edited November 30, 2011 by Dan Gleason Quote Link to comment Share on other sites More sharing options...
cd1105 Posted November 30, 2011 Author Share Posted November 30, 2011 Hi my name is Dan Gleason. I've done 2 turbo swaps successfully. First item, Did you install fusible links? The fusible links protect the wiring harness from overload. The links are 40 amp and 50 amp. These can be replaced by fuses. There is a green wire and a red or (brownish wire), both of these wires need fuses in line with them for amperage protection. The green wire uses a 40amp fuse. The brownish wire requiers a 50amp fuse. Since there are limited fuses available use a 40amp fuse on both lines. All the parts you need are available at Auto Zone or O'Reilys. You will be bying 2 40 amp fuses and 2 fuse holders. You will also need male and female spade connectors to attach to the red and brownish wire. Second item, you may have a short in the wiring harness. This part is time consuming testing for continuity from the harness to ground.Did this wiring harness come from a running 280zxt. If not I suspect the harness. You can contact me at gleason_d@sbcglobal.net Dan Gleason I have the fuses hooked up in place of the fusible links already although, I'm only using 20amp or 30amp fuses(forgot which one,I will check), but that's not the problem, none of the fuses are or have blown. All my relays come on like they are supposed to according to what position the ignition switch is in and so does the ecu. I haven't got a chance to hook up the ground wire to the starter as people in the post above have mentioned above, but i will in a few days. Yes the harness came from a running 82' 280zxt. Are you local? just in case I have questions.......... Quote Link to comment Share on other sites More sharing options...
beermanpete Posted December 1, 2011 Share Posted December 1, 2011 Did you clean all the paint and dirt off at the points where you are connecting the grounds to the body? Any paint or dirt will act as an insulator and restrict the current flow. Check for voltage drop across the ground path with your voltmeter. Connect the meter from the battery negative terminal to the starter motor/engine block. Set the meter voltage range to 15 or 20 volts (or whatever you normally use to measure the battery voltage). Crank the engine and read the meter while cranking. A voltage drop of more that about 0.2 volts is a problem. You can use a more sensitive range on the meter if necessary to get a good reading but start on the 15 to 20 volt range to protect the meter. Quote Link to comment Share on other sites More sharing options...
stav2201 Posted December 1, 2011 Share Posted December 1, 2011 You never made mention if you checked and verified your ignition timing. Alot of people run into this problem by putting their oilpump shaft in 180degrees backwards. Quote Link to comment Share on other sites More sharing options...
cd1105 Posted December 1, 2011 Author Share Posted December 1, 2011 You never made mention if you checked and verified your ignition timing. Alot of people run into this problem by putting their oilpump shaft in 180degrees backwards. oil pump shaft is in as the fsm states and looks. Dizzy Rotor is aligned with the #1 spark plug position at TDC. Quote Link to comment Share on other sites More sharing options...
Lloyd Posted February 5, 2012 Share Posted February 5, 2012 Was wondering how your build is going. I am currently coming to the end of my turbo swap and see if you could help a bit. I live in the bay area and can meet up or somethig. Thanks Quote Link to comment Share on other sites More sharing options...
cd1105 Posted February 8, 2012 Author Share Posted February 8, 2012 Was wondering how your build is going. I am currently coming to the end of my turbo swap and see if you could help a bit. I live in the bay area and can meet up or somethig. Thanks Will be glad to help. Pm'd Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.