Can you test a coil?

[bmohan55]

My Series recently has had a problem starting when it's damp or raining.

Recently replaced points, condenser, plugs, cap and rotor. I just ordered new plug wires from our hosts as that is the last thing I could think of. Can the coil be tested or is it more of a "working/not working" part? The coil is an Accel super coil of unknown age. I used a test light and determined that I am getting power to the distributor during the no-start times.

Thanks again
Bob

[SafeAirOne]

My Series recently has had a problem starting when it's damp or raining. I just ordered new plug wires from our hosts as that is the last thing I could think of.

I don't know about testing the coil, but my bet is on the plug wires. I'm guessing that your problem will go away with the new wires.

[thixon]

Yes you can test the coil.

My ranges are going to be aimed at a general 12 volt coil (like what you'd get at autozonenapaoriellyspepboysyougetthepicture), so someone else here needs to weigh in if my ranges are off a little specific to a OEM series coil. (they should be in the ballpark).

Set your multimeter low range. Testing from the postive side to the negative side you should be in the range of 2-3 ohms or so. If so, the windings should be fine.

Set your multimeter to high range (k). Test from the negative side, to the center of the coil (lead to the distributor). You should be in the 5000 to 8000 range.

Hope this helps. And again, my ranges could be off a little compared to a OEM rover 12 volt coil.

[Jeff Aronson]

It would be unusual for a coil to "fail" only when it's damp or rainy, unless there is a crack at the ceramic end of the coil. A failing coil usually manifests itself in "cutting out" or "bucking" under load, such as acceleration. The coil is usually not affected by rain or dampness, again, unless it's got a crack where the coil wire goes into the coil.

If the car starts when the weather is good, and you have time, start the car and with a spray bottle, soak each plug wire, then the distributor cap, and then the coil wire, and then the coil itslef. If the engine stumbles or stalls out, you've idenitifed the problem wire and/or coil.

If you do this at night or in a dark garage, you'll also see an arcing of light when the moisture "grounds out" the cracked wire.

Jeff

[lrdukdog]

My old AMC Rambler American SW had the same trouble ie. damp/wet weather no start. It was the coil and it was a hair-line crack that was the problem. I found it by taking a spray bottle of water and misting the ignition wires, dizzy etc. I then had SWMBO try to start it at night with me checking under the hood. It was neat all these little blue lightning flashes my, my. A few squirts of WD-40 and it started up. A new coil sloved that problem.
Jim Wolf

[bmohan55]

thanks, after intalling the wires I'll test the coil...

what is and where can I get a SWMBO, if I don't already have one?

[Jeff Aronson]

"She Who Must Be Obeyed" will let you know exactly how to procure one when you don't have one already. I'm still waiting :).

Jeff