Technical no spark

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Technical no spark

leafblower

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hey, i am a new fiat owner. i purchased a 78 spider yesterday. it's a restoration project. So here is my deal. I get no spark off the distributer at all. i did the screwdriver frame test. same test indicates that no electricity is running to the coil. (new battery has been installed) There is juice running into the coil off one of the wires. i figured it was a bad coil but usually a bad coil will do something... of the three wires running into the coil one was the ground the other doesn't appear on the wire diagram and had no power. any suggestions?
leafblower
 

Deckchair5

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Sorry, a bit confused. You say "indicates that no electricity is running to the coil. (new battery has been installed)" then you say "There is juice running into the coil off one of the wires"

What kind of ignition set up is it contact breaker? partial electronic?

LOW TENSION SIDE
If it's contact breaker then see if there's a flash at the contacts by pulling apart contacts with a screwdriver with ignition on.

Check the condenser

Check for power at the coil LT side (non earth) when you "break" the contacts

HT SIDE
Try a resistance check across the HT coil

Hold the coil HT output close to engine and manually break the contact breakers and see if you get a spark at the HT lead.

Check the coil to distributor HT lead resistance

Check the distributor cap brush

Check rotor arm for wear or insulation cracks

Check for hairline cracks, moisture in dist cap

Send in the results on a postcard:)
 
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leafblower

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i meant that power was going into the coil but there was no indication from my curcuit light that power was comin off the other side of the coil (from the cable running to the distributer).
 
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leafblower

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well, i am havin trouble finding my multimeter so i used a curcuit test light. it showed no current on the cable that runs to the distributer from the coil. So i assume no juice is runnin past the coil. i also checked the coil with my curcuit tester light to see if i could run current through it at all. it lit up off the battery so i assume it'll produce some kind of flow through, but i haven't tested for resistance yet. by the way it has the points type distributer (the screws for the cap were frozen so i had to soak em in breaker fluid and i only just got it off about 10 minutes ago.)
 

T14086

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The distrubutor will send a negative to the coil to trigger it,you should also have a ignition live at the coil...are these ok?
Do you have a circuit diagram?
 

Deckchair5

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"well, i am havin trouble finding my multimeter so i used a curcuit test light. it showed no current on the cable that runs to the distributer from the coil. So i assume no juice is runnin past the coil".

When the contacts are closed then the LT lead from the coil to the distributor is taken to earth, you'll only see voltage there when the points are open when the lead is then connected to earth through your condensor

With ignition ON check, using a Circuit Tester, that there is power on the + wire to the coil.

If there is power to the + side of the coil,
— remove the distributor cap and note to which lead the rotor arm is pointing or put the car in top gear and roll it until the rotor arm points to where the lead to the plug under test enters the distributor.


Refit the distributor cap
attach a spark plug to the lead under test and earth it by holding it against the engine
Remove the coil to distributor wire from the distributor and, with the ignition ON, touch it against the metal body of the distributor then remove it. As you remove it there should be a spark at the plug under test.

— If there is no spark, check the integrity of the LT wire. To do so: using a spare piece of wire attached to the same terminal on the distributor to which the wire is attached, touch the test wire to ground and look for a spark at the plug under test.

— If there is a spark then the wire has a break in it

If there is no spark; then check your HT leads for continuity and resistance
If they're ok then suspect the coil.

If touching the coil to distributor lead to ground at the distributor, does produce a spark.
— Check the condition of the contact breaker points.
— Check they open and close as the engine is rotated (or the car rolled forward while in top gear).
— If they are badly pitted or piled, replace them. While doing so, replace the condenser, although robust, its failure can be a cause of contact breaker erosion.
 
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T14086

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By the way it was worded I was thinking leafblower was using a test light to test for HT voltage!
 

Deckchair5

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Ha! Not recommended.
Better to get an idiot to stick their finger in the HT coil and guess the voltage by the screams:)
 
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leafblower

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when i first started with cars back in college there were loads of things i didn't know... that was one. it just shocked me real good... sucked bad...but i never did it again...i had a high school kid from my church do it this time...

ordered new points tonight. it's funny that they don't sell em in pairs...
 

Deckchair5

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Has two sets of contacts does it? The original wasted spark concept. Are you getting power at the contacts? Nice blue spark? Got a useful spark of the HT circuit yet?
 
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leafblower

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clearing space in the garage...its snowing too much too work on it the last few days so when i move it i'll start messin with it again... hopefully tonight after work or tommorow morning. i actuallybought one of the points cause thats all they had in stock. probably gonna start messin with the fuel pump too. needs to be primed or somethin...
 
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leafblower

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got in at the car this mornin...the lead to the run point of the distributor was disconnected and the points were pretty crappy. i set the start at .017 and the run at .019. ran some starter fluid in and rolled it over only to have the starter give out. ordered a new one and will go after it again on sunday (probably). i am also havin a hard time finding the fuel filter....any suggestions?
 
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leafblower

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yeah, sparks is half the battle...no fuel gettin to the carburator is another major bullet item...plus spart is kinda on hold till the new starter turns up in the mail..prolly friday or saturday.
 
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leafblower

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well, i found a new coil on the shelf of a local shop for only $15 so i replaced the coil, condensers, and points. found a brake in the electrical line leading into the running point. got the new starter in the mail and will install it in the morning. then i will go after the fuel pump... i am looking forward to the work...i'll post again in the mornin after the starter motor goes in. o, i found .017 and .019 as the gap settings for the points. it is a 78 spider, does anyone know if thats right? thanks for all the help by the way...
leafblower
 
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leafblower

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so here it is...i put a new starter in...not a fun task i might add. found out my alternator was also shot, but i put the old one back for continuity purposes. rolled it over, still no spark. the coil has around 7.4 volts running into it (it's new). the distributor has new point and a new condenser (i will have to fight the old one off) when it just sits there aint a lot of power runnin into the alternator itself. the two leads are both hot ut less than a volt. if i let it sit it starts to smoke and stink. so i disconnected the battery. that may be from breaker fluid i used to get one ofthe condensers off.but its long dried up and the other thing is that with the alternator not turningthere isno reason for it to be heating up and it gets hot quick.
 

Deckchair5

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Hi
Some gruesome tasks there then:)

Coils and heat
I expect you know that many ignition coils of that era have a ballast resisitor which knocks the voltage down to roughly half during normal running which is what the coil is designed to run on. This is so that at start up, the ballast resistor is by passed and the coil gets twice normal voltage ie 12volts for a good start boost. So your 7.4volts at the coil sounds right with ignition in the on position. BUT have you got the right coil and not a 12volt one? Otherwise things are going to get hot fast

Mind you, you'd still get sparks all right with ignition in the start position but wires would start to melt in the ignition position(n)

When did your engine last run? Have you seen it running?
 
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leafblower

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the seller told me that it had run 4 years previous. so running is not something i have yet seen. the coil was the one that was listed for the vehicle in the catalogue at the store. gonna try replacing the cables tommorow. the cable from the coil to the cap registered infinite resistance. so a new set of cables are next. try the dumb stuff last...
erik
 
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