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Tips
Tips

No spark while cranking

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philknight

Jedi Hopeful
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Gentlemen,
I have installed a gear reduction starter on my 73 TR6 (awesome difference, like a starter on steroids) and have found the straw that broke the camels back on my stock starter. I had disconnected the ballast resister wire connection at the coil and the white/yellow wire at the starter and had run a separate white wire to the coil in order to get a hotter spark. However, by doing this when the starter is cranking the white circuit is not energized. Is this normal or is my starter switch on the fritz? There is no additional terminal to hook the white/yellow wire to the new starter though I could bundle it with the white/red connecter at the starter to get juice while cranking. Or I am leaning towards running a wire from the brown circuit (hot all the time) under the dash to a kill switch then to the coil for cheap theft prevention.
Your thoughts por favor, Phil
 
I had a similar problem on my Cobra and I solved it with the separate wire directly off the battery through a toggle switch to the coil (actually the MSD ignition). It's a kill switch and even though it's right out in the open on the dash, it's unlabeled and makes an effective theft deterrent. Hope this helps.

Tom
 
That would cure the problem. If I tap onto the power feed at the starter and put an inline fuse before I go into the passenger compartment to a kill switch what size fuse would it take? Not shure how many amps the ignition draws.
I'm still curious as to whether the white circuit should be energized while the starter is engaged.
 
If the white circuit you're referring to is the power to the coil (or some other ignition system), then yes, it needs to be energized while cranking. The problem with tapping into your starting circuit is that the starter drops a lot of voltage and whatever is left is what your coil gets to produce a healthy spark, especially at startup. If your starter hogs too much voltage, guess what gets shorted? In the case of my MSD ignition, it stops working at 8 volts. If the world was a perfect place, your starter and battery would be brand new and in top notch condition and this wouldn't be an issue.

To minimize the effect of the starter you need to run a separate line direct from the battery to a toggle/kill switch on your dash and then to the coil. I would think a 5 amp fuse would be sufficient. Actually, I didn't use a fuse at all, even though I know it's good practice. Hey, I was in a hurry.

Tom
 
I would think it would be more effective to use the ignition circuit fed through a relay to power the coil. You could even jumper a wire from the ignition feed to the starter relay into another relay that would feed a full 12 volts to the coil. See the attached diagram. #87 would go to the coil. #86 would be the ignition feed that powers the starter solenoid.
 

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Don't let Cheapsnake fool you.....He PUSH STARTS his Cobra just to show his neighbors how tuff he is... /ubbthreads/images/graemlins/jester.gif
 
Hey you guys, don't go giving my secrets away. /ubbthreads/images/graemlins/lol.gif

Tom
 
JeffS has already suggested what I was going to mention. You can use a headlight relay powered by the red/white wire to supply the coil (+) terminal while cranking. As others have said, there should be battery voltage on the wire from the ignition switch while (and after) cranking.
 
Yeah Jeff, but if the starter is pulling the battery voltage down it will pull # 87 down too won't it??,if it's terminal # 30 connects to the starter battery terminal.---Keoke
 
As Keoke said, if you connect the relay coil between the red/white wire and ground it will see lower voltage than ideal. It will probably pull in though and it won't cost much to try. Generic Bosch-style headlamp relays are available at most parts stores for around $5. This is a much smaller investment than a late model starter solenoid with the extra (4th) terminal for ballast ignition connections.
 
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