Testing coils off the bike?

[Guest]

I took my coils off the bike to clean them up and replace the spark plug wires with suppression 7mm wires from Z1. I have searched the forum for testing off the bike and haven't found anything that seems to fit my situation. Thought it made sense to test them before spending the time digging the old wires old and epoxying the new ones in.

Can someone explain if this is possible and where I should be connecting my multimeter for testing?

Many thanks.

[Brendan W]

Set the meter to a low Ohm range 0-5 or 0-10 and check across the two low tension wires, supply and gnd. Looking for 3 - 4 Ohm depending on the coil. Mine are yellow and come in just under 4 Ohm. Then check between each and the core, metal frame of the coil looking for infinite resistance. Switch to higher range and check between the two high tension leads, ideally with the plug caps removed looking for 15 kOhm or more. The coil may have id on it to help track down the resistances for that part if you're not sure you have originals.
I'm sure it's in here somewhere http://members.dslextreme.com/users/bikecliff/ in the 850 manual.

[growler]

Not sure what wires you are talking about, my disconnected coils look similar to this. No wires besides the spark plug ones. Forgive my ignorance if I'm missing some obvious. :/

http://www.ebay.com/itm/1983-Suzuki-GS850L-GS-850-L-S439-ignition-coil-A-with-wires/291261313807?_trksid=p2054897.c100204.m3164&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D20140407115239%26meid%3D25660d1822a4495f8e0ee847aea960e2%26pid%3D100204%26rk%3D2%26rkt%3D3%26sd%3D350678868699

[growler]

this video is helpful.
https://www.youtube.com/watch?v=lYzrByJUoGY

[BigD_83]

In your picture, the low tension side to which Brenden referred are the two prongs, labelled + and -. The HT side is the side with the plug caps. You can do the testing by connecting alligator clips to the + and - posts. You do not need power to the coil to test for continuity.

[growler]

got it. thanks!

[growler]

Okay, here are my measurements.

Coil 1 + 4
between low tension prongs - 4.5 ohms
removed caps, between each spark plug wire - 12,000 ohms (12,080 ohms)

Coil 2 + 3
between low tension prongs - 4.2 ohms
removed caps, between each spark plug wire - 12,000 ohms (11,920 ohms)

My coils are an off white fleshy color. They say Nippon Denso and I believe the number is 129700? I'll try to find some info on their specs.

[growler]

Denso 129700-4000 (JO400 10D09)
- 4.7 Ohm primary resistance
- 17.4 kOhm secondary resistance

This means I need new coils, eh?

[Brendan W]

My 2c worth. Probably OK, I wouldn't bin them. Secondary resistance measuring is for me anyway an inexact science with inexpensive measuring kit. If one was 15k and the other 10k ,something is happening but the chance that two coils 'go off' by exactly the same amount is remote.

[tom203]

Those readings are fine. I've tested 4 sets of white fleshy color coils with similar readings.

[growler]

Great. Thanks for the help. Going to just replace my spark plug wires and epoxy them into these coils.

[Grimly]

Those readings are fine. I've tested 4 sets of white fleshy color coils with similar readings.

Ditto. I have a pair of those with those readings and they're fins