Weak Spark Problem??

Hi All

Got my carbs on and balanced, when I put my colour tune on, I had a weak spark in #1 cylinder, but a strong spark in #4. Now, the same coil runs these 2 cylinders, is it possible for a coil to breakdown on "one side" ?

I trimed the edge off the plug lead, reattached the plug cap, still weak spark. Tried moving the plug lead with the colourtune in and no difference, so I don't think it is a intermittant connection at the coil or plu end. All the earth points for the coils are spotless, tight and all the wiring is in good shape (no rust on cotacts)

Anyone got any ideas? Is it possible to put new plug leads into these coils, they look hard wired to me?

Thanks for any light that can be shed on this problem.
Lea

 

replacement coils are cheap and plentiful.

 

Had the sme type of thing going on. Rule out a bad pluge first by switching #1 and #4. If the weak spark changes with the switch--- then it is the pluge.

 

I would Ohm out the coil primary and secondary lines first, it could be that just the ignition wire is bad. Re-wiring the existing coil is not terribly difficult.
Obtain some 7mm copper core ignition wire.
Use your Dremel tool (or similar, the coil does not care) to grind around the coil body where the old wires enter the body until you expose the junction of the ignition wire and the secondary terminal.
Desolder the joint.
Solder in the new wire.
Re-pot the coil with epoxy, preferably PC-7 (or 11, take your pick) or JB Weld.
Go about your business.
Cost savings is about $100 each for stock coils new, $140 or so for aftermarket.

 

Pull the resistor cap and check that you have 5 ohms resistance. If more then replace the cap for about $5. Easy check is to switch plug caps with #1 and see if spark comes back. If it turns out to be the resistor cap then I would advise changing them all.