Ignition Coil Question??

So i was working on a lawn mower it has the Kohler courage 20hp the original coil was chewed up and had some burnt spots from a damn mouse nest. Anyway i bought a new coil installed and gapped.
Cranked engine and no fire so i pulled the ground/kill wire from the coil and it fired right up but as soon as kill wire is attached it dies. Yes key is on and i traced the kill wire for shorts nothing found. I hooked up the original and everything works.

The ground/kill tab on the original coil (not running) is reading as a closed circuit as it should but new one is reading open.
Is this pretty common for these style coils to do that? The Ebay seller is telling me it's a fault on my machine but i believe he sold me a faulty coil.

From what you tell us the coil is good, you have a short in the kill wire. Trace the kill wire back from the coil to the next connection point. Remove this connection and try starting. If the engine starts this section of wiring is good, reconnect and go to the next connection point and repeat. If the engine does not start, your problem is in this section of wiring.

Seems like this could be a safety switch problem, unless I misunderstood the OP.

To simply put it the lawn mower was running and working fine, Coil wire was just chewed up. So i put a new one on and it wouldn't fire. Unhooked the kill wire from coil and it works,hook it up and no fire. So i thought maybe switch or safety wire bad. Nope i hooked the original coil up and worked fine.

Mike.
Firstly the coil should not necessarily read closed to the kill wire.
There is a chip inside that makes & breaks the coil ground to create the spark.
It is an electronic version of a set of points.

These chips are very sensitive and can be destroyed by some cheaper Ohm meters.
This is why you will never see any tech on here telling people to meter their coils.
The gear needed to check coils ( actually modules ) costs thousands so no one has then because they either work or don't work and the test is to disconnect the kill wire.
Knowing if a winding is bad or the chip is bad is of no consequence to a tech because either way the coil needs to be replaced.
You test for a weak coil by increasing the free air gap to 1/2"

The embeded chips have a very limited advance range ( lack of retard actually ) and over the years there has been several attempts to make a better one that has a better advance curve.
Kawasaki had the best but all of the engine companies gave up because the mower companies would not pay the extra.
It is hard for a sales rep to explain to the average pig ignorant customer that this 15Hp engine will deliver more useful power than the 15.5 Hp engine in the mower next to it.
The public do not understand that it is torque that does the work not raw Hp.

Anyway getting back to coils, the various different timing systems used different coils so unless you went to an authorised Kohler dealer with your complete engine number there is a better than average chance you get sold the most expensive coil because they are not returnable.

If you bought it on line then it is a lucky dip as to weather you got a good one or a scrap one being sold as one that "fits" .