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Turns over and over but no spark

SamSly

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Aug 1, 2019
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Location
Las Vegas ,Nevada
77 B300 sportsman ,440, thermoquad,what I believe to be stock everything else. New coil, new cap,new rotor, new wires, new plugs, new alternator, new starter, used but last seen running ECU, new ballast , newish voltage regulator. Had her running somewhat decent, drove 400 miles south to Vegas and when we stopped near our destination it slowly went from running to rough running to crank like hell to start to finally no amount of crank would work battery dead situation. Can someone help me to run a "new" ignition circuit with all these new parts so I can tell my wife to shove it? My apologies in advance. Thank you as well.
 
77 B300 sportsman ,440, thermoquad,what I believe to be stock everything else. New coil, new cap,new rotor, new wires, new plugs, new alternator, new starter, used but last seen running ECU, new ballast , newish voltage regulator. Had her running somewhat decent, drove 400 miles south to Vegas and when we stopped near our destination it slowly went from running to rough running to crank like hell to start to finally no amount of crank would work battery dead situation. Can someone help me to run a "new" ignition circuit with all these new parts so I can tell my wife to shove it? My apologies in advance. Thank you as well.
Can you confirm spark at #1?
After 400 miles, I'm gonna say your fuel is good.
 
Make sure that the ECU is grounded well.
Check from ECU case to ground with a meter

If good, check the reluctor/pickup gap.
Sometimes the distributor shaft bushing goes and causes the reluctor to wear away the pickup and open up the gap.
Use brass feeler gauges to check the gap.
.008" is good
 
Yes, check grounds. But, check to make sure you are getting power to the + side of the coil with the key in the on position. Grounds and that 1st. That is after you've confirmed your are or aren't getting spark at the #1 sparkplug.
 
Check the gap on the distributor pick up.
I went through this just this week.
I would see spark on first revolution then spark would go away. Checked the usual stuff and chased down the gap in the distributor. Gapped it right, turned the key and the motor fired off on half a bump.
 
Bad Battery cables can also cause problems if they have too much resistance.

If you think it may be a voltage drop issue, test with two batteries. One to only spin the starter, and one to power the ignition. One of those small jumper pack batteries makes testing like this easy.

Setup: put ignition key in off position. Put a starter button on the neutral safety switch (or just use a jumper from the yellow wires terminal to the terminal the battery connects to (Just used for cranking the engine.) Connect other battery ground to ground, and the positive the blue key switched power wire at the ballast resistor. Use the starter button of jumper to crank engine, and if it fires up, the ignition components are fine, and the problem is either power getting to the ignition, or voltage drop in the battery cables or other wiring.
 
If you have voltage at the positive + side of coil, take a jumper and connect to coil - side, then tap the other end to a ground, and a spark should come out of the coil. Having voltage at the coil - side really depends on if the points (or ECU) are open or closed. I think with the ignition on, and not cranking the engine, the coils - is normally grounded with the stock type ECU?

I think if there is voltage at the coil - when key on, but not cranking, with the stock type ECU, make sure the ECU box has a good ground. After that make sure wire to the ECU is not broken or has a bad connection, Last, try a replacement ECU.
 
No spark at #1. Checked from coil and no spark there either. Getting 12v to both + and - at coil though. Is that correct?
I'd say if there's no spark @ #1 and you're getting voltage TO the coil, it's the coil.
 
things to try-

jump the ballast resistor

jump the coil to positive battery
 
...and always carry a spare brain.
 
Make sure that the ECU is grounded well.
Check from ECU case to ground with a meter

If good, check the reluctor/pickup gap.
Sometimes the distributor shaft bushing goes and causes the reluctor to wear away the pickup and open up the gap.
Use brass feeler gauges to check the gap.
.008" is good
Checking gap now then will give er a go. Really appreciate all the good input. Got good ground at ecu . The distributor connector has been cut so splicing in new end on wires coming from ecu and going to try a spare distributor that is gapped correct and has connector intact.
 
more likely the ecu then the coil versus the actual distributor
 
...and easier to swap out, so try those first if you have them
 
Gap is set .008 and still no spark. Got a buddy coming over to help trace wires ad check for bad anything etc. Will post tonight. Thanks
 
Gap is set .008 and still no spark. Got a buddy coming over to help trace wires ad check for bad anything etc. Will post tonight. Thanks
Leaky fuel line among the tangled salad of wires. My bud helped me to decide to start fresh so I went ahead and started to clear the mess of wires. Next post will more than likely be a cry for help in rewiring ignition but from the diagrams I've looked at it seems pretty straight forward. Went ahead and ordered the ignition control harness so I can have a good solid connection. Wish me luck boys and thanks again men.
Ps. And women too if applicable
 
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