Technical no spark

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Technical no spark

"the cable from the coil to the cap registered infinite resistance"

What's that the HT lead? Should be about 4k-12k max depending on lead. infinite resistance is for the bin!

If it's the LT lead then that will show zero to high resistance depending on whether the points are open or closed
 
replaced the cables, but no spark yet...i have an extra condenser that doesnt appear on the wiring diagram. it comes of the coil on the negative side. plus looking at the wiring diagram i think the coil is wired in all wrong anyway. the brown lead from the ignition relay runs into the positive terminal, while the blue black lead from the ignition switch also leads into the positive terminal of the coil. the negative has only a condenser tot he ground. the wire digram has no condenser witht he blue/black wire and the brown wire entering on opposite sides with teh letters b+ and d so i am thinking that the coil is wired wrong. i'd rather not ruin the coil. any guesses?
 
The condensor on the coil will be a radio suppressor. The coil will work with or without that. Disconnect it for now just in case it's shorting to earth

Re the two LT wires to the coil +ve from the ignition, one will be providing a direct 12v only when the key is in the start position and used just for starting to provide 12v to the coil. The other LT wire will be producing 6v via the ballast resisitor for normal running to the 6volt coil

A test you can do for the ballast resisitor and wiring is to connect the coil neg to earth by using a wire with a crocodile clip on both ends. With ignition on, check the voltage at the + side of the coil- probably about 6volts or so. Then get someone to turn the key to the start position, the starter soleniod should now bypass the ballast resistor and a full 12volts should now be seen at the same point

If you have 12v at the coil on start and 6 volt with ignition on then that's that side checked and you can move on to the distibuter contacts etc

Put everything back to normal and just flash the points apart and see if you can get a spark out of the coil HT lead when held close to the engine


Check the distributor cap for tracking marks and cracks while you're scratching your head:)
 
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Bad relay module? What relay module's that then?

Going back to the coil, if you've got 6volt (or even better 12v) on the +ive LT side and an earth on the -ive LT side then, provided the coil is 100% then it's sparks time:)
 
ignition relay is the thingie in the dash that the two wires from the coil go to along with the brown wire on the - side of the coil. hey, i unhooked the condenser from the coil, still no spark. Then i tested the two wires from the points to the ignition relay and they aren't lighting the tester up. also the brown wire that runs to the coil won't light the test light. so i am guessing i have bad wiring or a bad relay.
 
uhhh correction...the ignition relay is the thing in the dash that the two wires from THE DISTRIBUTOR not the coil. also the brown wire from the coil goes to it. the black wire from the coil goes to the ignition switch.
 
Do you have a wiring digram for this one? Can you post it up if you have one? You could easily bypass the ignition supply for testing the coil but don't run a 12volt coil on the 6volt supply from the ballast resistor if you have one
 
IT'S ALIVE! heh i lot of rewiring and a mess of research yeilded my spark this morning. asit turns out the duel point ignition in the 78 is for emisions only and decreases performance. the problem seems to have been in the switch. i rewired it to a single point system, which is contrary to california emissions but not indiana... http://www.international-auto.com/index.cfm?fa=ad&aid=68 found it here...pretty cool website...thanks...YAY
 
Excellent. The girl lives!! :)
Good find with then wiring diag. Interesting and bizarre points set up. Fiat just love making something simple that little bit more complicated.
Won't be long now then. Can you post any pictures of the gal?
 
the pics are in the gallery. she doesn't look like much but for a 30 year old indiana vehicle its pretty solid. very little rust. bought material for the reapolstering yesterday...suede...she will run once i take care of the fuel pump...i think i will probably do an inline solid state electronic fuel pump. picked it out and just have to save up some money...
leafblower
 
WEEELLL...I am right with ya on this one...I am just curious as to the ballast resistor...do I have one...do I need one? my coil says there is one built in...is that the wrong coil...I have a dual point dizzy too, and converted it to one point set. 12 volts at the + terminal on the coil...well 11.8...Battery is a little weak, but I have spare battery I hook up as a jumper..no current across the 2 terminals + and -...and of course no spark off the HT wire goind to the dizzy....any help or ideas would be appreciated.
 
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