ignition Blues

[72bumbee]

Can I swap a Mallory unilite ignition with a pertronix unit with relative ease?
for some reason the the Mallory units are frying because of voltage spikes?

[72bumbee]

ALSO...... would I be better off just going back to original factory dizzy guts?

[Lee]

Hum,.... I would think this would be an OK swap.... curious why you are frying Unilite's.... have had mine for 18 years....

[72bumbee]

I had my mechanic explain it to me... I have a hard time understanding it all.
Something about voltage and a condenser and I don’t know what all? He was holding the schematic of the unilateral module and pointing to some doohickey that was in line between the voltage regulator and the unilite letting not enough voltage through or perhaps just not the correct amount.... basically he was saying it was toast and he suggested going back to the factory distribution.
I was kind of helping the tow truck driver load my baby and sort of half listening. I could consult him again if it would help.
Also I can’t seem to locate the doohickey that was in the line on the schematic.

[Ranchero50]

The only doohicky is the resister wire that's hidden in the wiring harness behind the dash. Possibly that would drop the running voltage to the Unilite. You'll need it in place for the factory points setup.

[72bumbee]

So how hard is it to find the resister wire? I thought the mechanic was motioning towards the bundle coming through the firewall that went to water and oil gauges?

[colnago]

I don't know anything about Mallory, but when I converted from points to Pertronix, I was able to bypass the ballast resistor. Maybe the Mallory can't handle the full 12V voltage. This means that if you go back to points, you will have to make sure the ballast resistor wire is in place, or that you install an aftermarket ballast resistor.

Joseph

[sargentrs]

Any time I swap to electronic ignition, Pertronix, Duraspark, whatever, I always wire in a relay to pull source voltage straight from the battery so I get the full 12v without anything interrupting my source.

[72bumbee]

Okay, now I have a better idea of what I’m dealing with. After looking at the actual part that is called a ballast resistor do I need to see if I actually have that little doohickey? Just from perusing the sight I’ve seen other questions concerning this little gem.
This truck is driven maybe once or twice a year, so I get a lot of Oregon rain falling on it. I usually dump the condensate out of the air cleaner pan before starting and always fill the tank when finished driving .
Could I pop out the dash gauges and be able to see the actual ballast resistor? Could I just use the new temp and oil gauge wire bundle I ordered and assume there is a ballast resistor wire already in place? What kind of connector should I use to hook it to the coil? Brass or just whatever will do? No special metals needed?

[colnago]

The stock ballast resistor is a pink wire behind the dash. You should be able to get to it without pulling anything out. I don't think the coil is particular on the type of metal, but you can't go wrong with a brass lug.

I don't remember the exact voltage levels, but if you turn the ignition to "run" (don't start it, just turn the key to "run," but don't leave it too long without it running), and measure the voltage to the (+) lug of the coil. If you measure 12V or more, you don't have a ballast resistor. If you measure 9V or less, then you do have a ballast resistor.

I don't remember the resistance level, but you can get either a ballast resistor wire or an actual ballast resistor on eBay or Amazon, if you need one.

Anybody, please correct anything I got wrong.

Joseph

[72bumbee]

Thanks Joseph,
I’m now in the process of locating my multimeter... last time I had it out I was working on the 12 volt lights in my trailer house. Of course, no one else in the house even knows what I’m looking for.......