GS300 Coils? How do I determine power side?

[Guest]

I recently bought an 82 GS300L and previous owner replaced the coils in an effort to diagnose and repair a no spark on left side problem.
The problem is, I'm not sure the wires are on in the correct position. How do I determine where they go? Wiring diagram shows differently than the bike.

[tom203]

Did you clean them well and look for + mark on coil? Since these are replacement coils,have you "ohm" tested them ?

[kymasabe]

Well...no, I haven't. I didn't know pos or neg would be marked on the coil. Plus, they're not new coils, they're used coils from eBay. I am getting spark from them on the right side of the bike. The little GS has a bad CDI box so I'm working on trying to solve that problem too. But when I looked at the coils, the power wires are in the same position on the left terminal of both coils. But in the wiring diagram, it shows the power wires on the outside terminals so...didn't know for sure where to put the orange power wire.

[OldVet66]

It will work either way, but if it is reversed the secondary coil will fire from the spark plug shell instead of the center electrode causing about a 20% loss of power that might show up at idle or under a load. It probably doesn't matter for your diagnosis but will matter when you get further along and get it on the road.