Replacing the original coils

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nortonmargie

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I have a problem with Norton dying after about a quarter mile of perfect running (its a Mark III 850 with Pazon ignition) I tried testing the coils with an ohm meter: one reads 2.5, the other 3.2, but both intermittently either go higher or go to zero. I plan to do more testing, but am soliciting suggestions for replacements.
Thanks folks!
 
nortonmargie said:
I have a problem with Norton dying after about a quarter mile of perfect running (its a Mark III 850 with Pazon ignition) I tried testing the coils with an ohm meter: one reads 2.5, the other 3.2, but both intermittently either go higher or go to zero. I plan to do more testing, but am soliciting suggestions for replacements.
Thanks folks!
Click to expand...
You should have two 6 volt coils. 6 volt coils across the primary connections with nothing connected should measure 1.6 ohms. With the jumper between the two and nothing on the other terminals it should be 3.2 ohms across the two coils. If your measurements are correct, you have one bad coil and one 12volt coil. But I doubt that your measurements are correct - look like you are measuring with wires attached.

I doubt that your problem with running fine and then dying is the coils unless the Pazon is not working right with them. Call me.
 
Coils either work or they don't .
More likely old oxidized wiring harness connectors , worn out ign . switch or fuse connector or any other old neglected electrical stuff .
 
Does the offending motorcycle have a SPARK when it quits? (Spark plug in the wire, laid on the head, engine kicked over) Keep a spare plug in your pocket to test quickly.

FIVE second test.

TEST, don't guess.
 
Last edited:
Coils can fail after being subjected to voltage and overheat but then recover on cooling, on a Commando that's not helped by the clamps used to mount them having the ability to crush the bodies causing internal shorts.

I had one coil fail on a C15, it took 10 mins to heat up and produce no spark. Then you had to turn off the ignition and wait 15 mins before getting another mile or so and then repeat.

I also have stopped a Boyer from working by having low ohms coils fitted, too much current and the box stopped working. Again it recovered on cooling etc. Once I swapped to high ohms coils the box has worked to this day.

So could be coils or coils affecting the box.
 
I'm with kommando on this one. I had a coil that would break down after it heated up. I did the normal volt meter tests and it seemed good. I verified it by switching sides, when the problem moved with the coil I just went out and bought a set of PVL's.
I'm not saying this is your problem, just letting you know that they can fail when they heat up or get under load.
 
I run TriSpark coils now although there was nothing wrong with the original Lucas 6V. ones . Advertised as having bigger stronger spark . Quite affordable too . Maybe pick up a pair and fit them ? Then you would know if the old ones were on the way out too .
 
I have the new coils and am planning to put them in today. Am nervous about changing out the spark plug wires. Any tips on removing the wires and then replacing in new coils. The existing wires are in excellent condition. I checked the plugs, they look good and are the same color.
 
nortonmargie said:
Am nervous about changing out the spark plug wires. Any tips on removing the wires and then replacing in new coils.
Click to expand...
The plug wires should just pull out from the old coils.

Push them into the new coils as far as they will go.
 
HT leads generally pretty durable and R&R from coils and plugs never been an issue for me. Just don't pull on actual cable. Grab the boot and squeeze so you are pulling at/near the terminal within the boot.
More concern should be given to the coil mounting bracket-clamps. Do not over tighten,squeezing the coil casings. Some folks uses washers to space the clamp apart enough to prevent squeezing damage and having good bolt torque.
 
kommando said:
Coils can fail after being subjected to voltage and overheat but then recover on cooling, on a Commando that's not helped by the clamps used to mount them having the ability to crush the bodies causing internal shorts.

I had one coil fail on a C15, it took 10 mins to heat up and produce no spark. Then you had to turn off the ignition and wait 15 mins before getting another mile or so and then repeat.

I also have stopped a Boyer from working by having low ohms coils fitted, too much current and the box stopped working. Again it recovered on cooling etc. Once I swapped to high ohms coils the box has worked to this day.

So could be coils or coils affecting the box.
Click to expand...
I had the same problem when I first bought my fastback, coils heat up & stop, cool down & go again. Took me a while to find the coils were clamped too tight. I binned them & fitted a single twin coil, 5 years no problem.
 
I swapped out a pair of original (squashed) intermittent coils with some Remax or Rita ...can't remember ?(were gold coloured) coils....they have been fine for years...especially in original form 😉
 
A twin coil that meets your electronic ignition spec is better than anything Norton ever put on a classic Norton as far as not having to think about whether or not the coils are working goes. A twin epoxy coil is a "Test don't Guess" solution that works. Ask Matt at CNW.

Using things that work is going to ruin the mine is all original theme though. lol
 
Schwany said:
A twin coil that meets your electronic ignition spec is better than anything Norton ever put on a classic Norton as far as not having to think about whether or not the coils are working goes. A twin epoxy coil is a "Test don't Guess" solution that works. Ask Matt at CNW.

Using things that work is going to ruin the mine is all original theme though. lol
Click to expand...
The Tri-Spark coils I bought look the same . Can't tell any difference . Advertised as better . Good enough .
 
Getting to the guts of it 😎
 

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