dizzy help

Post by **katanaman** » Wed Aug 22, 2007 9:46 pm

You shouldn't have a condenser.
the only thing going to the - on the coil should be the dizzy/amp and the rev counter if your using one. There shouldn't be a ground as the ground from the dizzy is what is used to fire the coil. If you put a ground on the coil you are effectively short circuiting the the dizzy so you wont get a spark.

ChrisJC · Post by **ChrisJC** » Thu Aug 23, 2007 7:02 am

There should be a +12V feed from the igntion switch going to the amp +ve and the coil +ve
There should be a wire between amp -ve and coil -ve. And this goes to the tacho too as Marki says.

If you want to check the coil is working, put +12 on one side (turn the igntion on), then remove the wire from the -ve side and temporarily connect the -ve terminal to ground. When you disconnect this temporary wire from ground you'll get a spark. Be careful of both the spark, and the voltage on this temporary wire - the -ve terminal of the coil will get up to about 400V when the spark occurs.

A thought - you need to check that the amplifier is well grounded to the chassis.

Chris.

jrv8 · Post by **jrv8** » Thu Aug 23, 2007 9:03 am

wow wrote:hi,

and just an earth and a - going to the dizzy amp on the - side of the coil.

You do not need to connect an earth to the (-) side of the coil.

The wiring should be :-

Amp (-) to coil -
Amp + to coil +
+12v to coil +
tacho to coil -

Regards
Jim

wow · Post by **wow** » Thu Aug 23, 2007 11:14 am

Ok brilliant thanks for that.

well i have been and bought another new coil. still nothing .

someone told me that when i crank the engine the voltage on the - side of the coil should pulse drop off and then back up to the 12 v. which it is not doing it drops to 11.5v until i stop turning the key then it comes back up to 12.4v it does not pulse.

is this right if so what controls that bit.
thanks

jrv8 · Post by **jrv8** » Thu Aug 23, 2007 12:11 pm

Hi,
Remove the earth connection that you have on the coil neg.
It will never work with this connected.

Jim

wow · Post by **wow** » Thu Aug 23, 2007 1:30 pm

i removed that as soon as you said before. is the volts ment to pulse and if so what controls that is it the bit the amp plugs to in the dizzy ?

ChrisJC · Post by **ChrisJC** » Thu Aug 23, 2007 1:31 pm

Read this:
http://www.kronjaeger.com/hv/hv/src/ign/index.html

The switch, capacitor & resistor on the diagram (1st circuit diagram) are all contained within the amplifier. You can see that the coil has three connections, one +12, one to the amplifier and one to the spark plugs.

The amplifier has 3 connections, +12 (to power it), ground, and the wire to the coil -ve. It will also have a connection of some sort to the distributor to pick up when to fire the coil.

As to your question, using a meter to look for a changing voltage, it depends a lot on the meter as to how it will behave as the voltage is changing rapidly and the meter may not be able to keep up. I would say that +11.5 whilst cranking suggests that the amp is not connected correctly or is duff because I expect the battery voltage drops to 11.5V whilst cranking as well........Prove this by disconnecting the coil -ve and doing the same test......

Chris.

wow · Post by **wow** » Thu Aug 23, 2007 3:45 pm

so if it is the amp, will the amp earlier on in this post the intermotor one work with my distributor, i have the new dizzy with the amp on the side.

cheers for all your help

bodger · Post by **bodger** » Sun Oct 21, 2007 12:35 am

jrv8 wrote:
wow wrote:hi,

and just an earth and a - going to the dizzy amp on the - side of the coil.

You do not need to connect an earth to the (-) side of the coil.

The wiring should be :-

Amp (-) to coil -
Amp + to coil +
+12v to coil +
tacho to coil -

Regards
Jim

also if it's an EFI , the ECU trigger wire from the neg terminal on the coil too