Old ignition

[dguy]

I'm talking points & condenser kind of old, which means that I'm probably forgetting something.

+12v at the coil, resistance check of the primary & secondary windings says that hasn't opened or shorted internally.

Points are clean.

Cap & rotor show the small amount of pitting that you'd expect from a "barely used" pair.  No noticeable carbon tracks in the cap.

Points, condenser, cap, rotor, wires, plugs, and coil are 10-12 years old but barely seen an hour's running time.

No spark though.   

Have I missed something, or is it time to start throwing parts at it?   

[Kevin]

Would this car have a ballast resistor? That part would go without warning. 

[dguy]

Would this car have a ballast resistor? That part would go without warning. 

I had to go look that up, 'cause I had no clue what you were talking about.  Usually when someone says "ballast" I think of fluorescent lamps.     There's a nice little description here if anyone else is curious.

There doesn't appear to be any such animal in the engine compartment.

I'll have to check & see if the coil still has voltage on the primary when cranking; I've only checked it with the ignition in "run" so far.  If there's nothing there when cranking, I'll see if I can find a ballast resistor under the dash somewhere...

Thanks for the tip!

[dguy]

After a bit more testing, it doesn't behave as though there's a ballast resistor in there--there's a full 12v on the coil in RUN, and about 9.5v or so when cranking.  If it had a ballast resistor the coil should be seeing less than 12v in RUN.

Something hit me last night which I'm going to try though.  It's a beer can-style coil which grounds the secondary windings through its body and a half-moon sheet metal bracket.  The bracket is separate from the coil...  I'm going to pull the coil off and wire wheel the areas where the coil & bracket contact each other as well as the bracket-to-block connections. 

[FieroBUZZ]

Have you tried finding a Mustang guy who may lend you 'known good' parts to track down the culprit?

You could always add one of those electronic ignition systems that fit in the dizzy and look stock.

[dguy]

Have you tried finding a Mustang guy who may lend you 'known good' parts to track down the culprit?

No, not yet.  I'm actually having a small amount of fun trying to sort the silly old thing out "the hard way".  Among other things, it was strangely refreshing installing an engine from above the car instead of from below.   

You could always add one of those electronic ignition systems that fit in the dizzy and look stock.

Thought about it, but those kits cost close to three times what a replacement condenser & points set, or a replacment coil is worth.  If we were keeping the car I'd do it in a heartbeat, but we're not.  All she has to do at the moment is run well enough to move up/down the driveway under her own power.

[dguy]

After discovering that the secondary windings of a replacement coil from NAPA had a resistance of about 2k ohm higher than the old coil, I decided to replace the thing.

Combine that with a cleaning of every connection from the points to the plugs, half a liter of methyl hydrate in the tank and some encouraging words, the old beast finally woke up.


Anyone interested in giving a '68 Mustang some lovin'?  Any reasonable offer takes it.   

[indypacecar]

I would like to see some pictures of that. You have me interested!!!
  I can t seem to figure out how to post pictures of my seats for you, sorry.
Thanks Sean

[dguy]

I would like to see some pictures of that. You have me interested!!!

I'm going to take a few more photos this afternoon, and set up an online album.  Keep half an eye on the Non-Fiero buy/sell section.

  I can t seem to figure out how to post pictures of my seats for you, sorry.

Not a problem.  One of these days I'll either remember to bring my camera with me or get Kitten out to see them if she's not working.