coil randomly stopped working and it's not the coil

[scope]

hey

we had my 5k running for about 5 mins then went to try again but no spark. we changed coils but no luck. all the fuses are fine, we didn't touch anything inbetween having it running and trying to restart it except for moving it to TDC and taking off the dizzy cap

what could the problem be? could that ballist resistor or whatever it's called gone bye bye?

unless the coil we tried was also $&#$% but yea, checking other things first

any help
thanks

[Lloyd]

Points or electronic? Got power at the coil?

[scope]

points and yes, well i presume so since it was working earlier, didn't touch anything. even putting the 5k in, didn't play with the coil at all so i dunno

[SUBARUCONVERT]

are u sure u put it back togeather properly? no missin rotor? test if u have earth (when the points are closed) and power at the coil, if the ballast resistor is dead when u crank it will run but as soon as let the key off it will die

[scope]

scrap what i said early, pretty sure there's no power at the coil. what could be causing that? dodgy connection somewhere maybe? seems weird that it was working then just stopped

[Crucible]

You need to check it with a test light, if you have power, check power at the points, when they are closed the lamp will be out, when they are open the lamp should light up.

you can crank it over with the test lamp on the neg coil and the lamp should pulse, that will mean the contacts are switching.

another quick test is to put a test plug on the coil lead and switch the contacts with a screwdriver, if you have no spark at the plug its primary, if you do have spark its secondary.

[Bling]

very similar problem with my 4k, only way I can get it started and staying running is to put 12v straight from battery to positive side of coil, runs like a dream if I do that..... but cant get it working any other way. I've rerun every wire attached to the coil!! doesnt turn off using this method

[Lloyd]

BZG|Bling, find the wire that makes it go or not go and just run that back to the key so its only live when the key is on

Scope, do the tests as True-No-Turbo said. If you have power at the coil and a pulsing earth then you should have spark. If not then its a fault with the secondary side of the system which would either be in the coil or the coil lead

[scope]

i put 12v up to the coil like BZG|Bling and got spark down the lead so that means it's not getting power? could a wire be rooted somewhere?

[SUBARUCONVERT]

have u checked the ballast resistor, also im pretty sure they have some kind of ignition system fuse (not familiar with old toyotas)

[scope]

yea i checked the ballist resistor no luck. when i used to crank it over, the rev counter used to jump up and down a little bit. now it doesn't move at all so it is the coil?

don't have a test lamp to test the other stuff but some dude came over and checked power at the points (dunno how, think the way with a screw driver true-no-turbo said)

[Bling]

I ran a new wire from my ignition to the coil and it works fine now, cheers HRT didnt see that reply in time, but it was on the money.

[scope]

maybe i should do that since it sparked when i ran a wire straight from the battery to the coil..

[Bling]

Yeah I have no idea why it didnt work on mine either, but running the line straight from ignition wire at the barrel thru to the coil + (if I remember right) it fired up straght away. maybe just dodgy old wiring.

[scope]

what colour is this wire ?

[Bling]

black or black and a colour not much help, this is on a starlet anyway so may be different, but if you check the wires where they enter the barrel, they should be labelled.

[scope]

i will give this a go then

[scope]

doh, when i moved the dizzy cap i was earthing out one of the wires connected to it on to the block

nice one

[SUBARUCONVERT]

are u sure u put it back togeather properly?

[Bling]

^^^