Coil Readings

In an attempt to determine the cause of my lack of spark, I tested the two coils in my possession with my multimeter and came up with the following:

67 Midget Primary 3.4 Secondary 6790
73 Midget Primary 3.8 Secondary 6850

I have read elsewhere that the primary reading should be lower and the secondary reading should be higher. Can anyone either confirm or reject the readings above. Also, any comments would be appreciated.

Thanks......

First figure is correct for internally ballasted coil. Second figure seems low but does it make a nice hot spark?

The first reading, like Michael said, is good for an internal resistor coil, the second seems abit low, I always look for a reading somewhere around 10,000 ohm.

You say you've got a lack of spark...if you could be more specific about the spark problem & give a little more info/history, maybe somebody can help with the problem.

:)-D

Thanks to both of you for the reply.

I am just starting to track my "no spark" and started with the coil.

I also looked at the distributor and the points looked ok. I took them out and filed them a bit. I think I got them reset to the 15 thous and could not appear to be able to open them much further but they appeared okay when they hit one of the 4 lobes on the shaft. Does that plastic part that hits the lobe tend to wear very quickly?

The cap looked ok, no cracks or tracks.

I tried to test the condensor but didn't get a reading and I will try again when the weather warms up a bit. To my knowledge, when I attach 1 clip of my multi meter to the main wire from the top of the condensor and touch the outside of the case I should get a reading (but didn't the first try).

Would I get a spark if I attached a plug directly to the coil wire and grounded it to the block?

Thanks..........Brian

Here's a good information site, go to the ignition section & follow the process, it should put you on the problem:

http://www.mgcars.org.uk/mgcc/midgetreg/workshop.shtml

Here's another good guide:

http://www.mgexperience.net/journal/oily-hands&PageID=1#jid-4951

Easiest thing is to pull a wire from a plug, insert a screwdriver into the end of the wire, hold the (insulated!) screwdriver so that the shaft is close (1/8"-ish) to a clean metal surface, like a head stud/nut and crank over the engine. "Snap, snap, snap" with accompanying visible flashes is "good to go" regardless of any other tests. Trouble may be in the plugs (or not spark related). Or maybe REALLY wacky timing.

If you don't get a spark, work your way back. My most common issue seems to be a ground-fault in the points assembly.

Double check you have a good ground connection chassis to engine.