Ignition Amp & trigger head

[Steve_D]

Does anyone know of a way to test each of these on the bench?
Are there any static resistance readings across pins etc.
Does any other testing involve a scope.

Thanks
Steve

[blitzracing]

The trigger head is just a coil of wire, so a simple resistance check should be good enough- Its about 3k ohms. You could check the coil out by grounding and releasing the -ve terminal and see if it produces a spark with the amp unplugged. If both these pass, and you have no spark, then swapping the amp would be the next port of call. The signals are so small on the input you wont be able to measure much with a meter.

Ive done a bit here:

http://www.g33.co.uk/pages/technical-ignition-syst...

Edited by blitzracing on Tuesday 11th June 20:23

[Steve_D]

Hi mark thanks for replying.
Asking the question as I now have a collection of items I need to test.

The back story.
Non starting car no spark. 9.30 Sunday evening desperately trying to get a car completed for a customers deadline.
Had a new coil on the shelf so tried that...no joy. Popped a spare ignition amp on still nothing.

Went to move the coil that was laying on the engine and got a spark from the case. Tested it and found the primary was shorted to the case.
As well as being well pissed off that a brand new coil was duff i'm wondering if the dead coil could have taken out the ignition amp or trigger. I can't think that it would but not sure.

Finally got the engine running on a different coil and different dizzy.
Went back from there and found the original coil not working and neither of the previous amps.
This would seem to indicate that the initial problem was a dead coil....the new coil was shorting....so did that take out 2 ignition amps.

Steve

[Belle427]

Maybe make up a bench test rig with an old dizzy, coil and amp.
Spin the dizzy up with a drill and measure spark kv at the plug with a tester?
Probably something id do if it were my living.

[Penelope Stopit]

Belle427 said:

Maybe make up a bench test rig with an old dizzy, coil and amp.
Spin the dizzy up with a drill and measure spark kv at the plug with a tester?
Probably something id do if it were my living.

This is what I do/did/done......never fails

[blitzracing]

A shorted coil will certainly blow the amp- I think the coil normally draws about 7 amps, and being a semiconductor switch it will fail if you over current it.

[Loubaruch]

Steve,

If you are going to set up a test rig it may be worth having a hairdryer handy to test the ignition amp under heat. Some seem to fail that way.