Help Please! My Baby Wont Fire!

[Robbos_Toyotas]

Hey all
The little windsor v8 in my ma61 is playing up on me...it just wont fire!
It turns over, seemingly like it has plenty of compression...It has fuel as i took the aircleaner off and tested it by hand watching the jets work...
it runs a mallory unilite electronic dizzy, massive mallory coil. there appears to be no spark
IT was running fine, and it was all off a sudden this problem happened.
One thing i noticed is when i try and crank it over, theres massive voltage drop. I held a long piece of wire on the coil + and tested it to ground...11 odd volts with ign on - thats fine given the 3m length of wire..but when i try and crank it, it dropped down to only just 8v. Looking at the voltmeter on the dash it also confirms theres massive drop.

can anyone lend some advice?
Thanks
Robbos_Toyotas

[MWP]

First thing to check is your grounding wires and connections.

[hemi twofifteen turbo]

So is the engine cranking slowly or usual speed? If it's still cranking normal speed and you have no spark then it's going to be either the coil ignitor, the coil itself, or the pickup. I'd say check ignitor, coil, and pickup in that order. The voltage drop can be normal under cranking, but if you've got slow cranking it's probably a bad earth, dirty terminals, or a dead/dying startor motor.

[Robbos_Toyotas]

So is the engine cranking slowly or usual speed? If it's still cranking normal speed and you have no spark then it's going to be either the coil ignitor, the coil itself, or the pickup. I'd say check ignitor, coil, and pickup in that order. The voltage drop can be normal under cranking, but if you've got slow cranking it's probably a bad earth, dirty terminals, or a dead/dying startor motor.

no it is cranking normal speed.

coil ignitor? i dont believe i have one of those in the ma61...i just hooked the coil up to the ign sw...and the dizzy module for the - terminal. Its been like it for 2 years...only now this problem..

so how do i check if the coil is rooted?

[unleashed__]

no it is cranking normal speed.

coil ignitor? i dont believe i have one of those in the ma61...i just hooked the coil up to the ign sw...and the dizzy module for the - terminal. Its been like it for 2 years...only now this problem..

so how do i check if the coil is rooted?

put a screw driver in the end of the lead that comes out of the coil and earth it over a bolt.. you probably need 2 people to do this.. while one person is earthing it over a bolt.. the other person cranks the engine.. if there is no spark jumping from the coil to the bolt then your coil has had it

[Robbos_Toyotas]

put a screw driver in the end of the lead that comes out of the coil and earth it over a bolt.. you probably need 2 people to do this.. while one person is earthing it over a bolt.. the other person cranks the engine.. if there is no spark jumping from the coil to the bolt then your coil has had it

its as simple as that, no other problems to check for before saying its shagged?

will a bosch carby type coil from supercheap do the job temporarily?

[unleashed__]

its as simple as that, no other problems to check for before saying its shagged?

will a bosch carby type coil from supercheap do the job temporarily?

nope thats it.. like what one of the other guys said.. check all your other components in your ignition system.. it is easy to check the coil anyway will take you 2 seconds..

[Robbos_Toyotas]

ok no worries, if it doesnt become conclusive, hopefully someone will be on here tommoro!

[Grega]

hmmm
as discussed
water in fuel if its been sat for a while?
maybe jump +12v to coil if weak spark and not getting enough power as a test?
check for vac leaks - as u're carby they can do with good signal
let us know how u go

[Robbos_Toyotas]

ok guys
I bridged power to the + terminal from the battery - it says 12v when i ground the + coil to the chassis. drops down a little less when cranking.

I put a drill bit tight into the coil lead - no spark at all onto exh manifold.

I pulled a plug - once again no spark.

dead coil?

[jeffro ra28]

i didnt bother to read the other posts.
Do these mallory dizzy's have an optical eye as the signal to spark?

They fail alot. Usually they are blue, if they have shat they turn black.

[Robbos_Toyotas]

Nah mine is a red module, the lenses look clear/ whitish?, but it is the optical thing you say....

And after doing some tests on the coil including buying a new one, the old coil seems fine. So it must be this module....is there any way of testing the modules?

edit: the dizzy is a mallory uni-lite.

[Robbos_Toyotas]

thank god for the internet!
found this site

http://www.centuryperformance.com/mallory/unitest.asp

I did the test and voltage didnt drop so its shagged...theres a lesson for all...dont use electronic igniton without a ballast resistor....

Will buy a new module early in the week and keep you posted.