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97 GSX Ignition coil test--did I do it right?

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Major Woody

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Hello all. Was just hoping I could get someone to confirm for me that I have tested my coil properly before I order a new one.
Engine died out on the water while cruising. Did not die after jumping or after long WOT run--just died. Cranks over vigorously. Brand new battery, voltage 12.5. BUT no spark at either plug. Checked all connections and grounds. NO corrosion inside rear E-box. Checked coil primary with spade connectors off, and it is fine. Removed plug wire ends, checked each of them for proper resistance, and they are fine. Then checked resistance between end of plug wires and a good ground. Found open circuit--no resistance between either plug wire and ground. I assume this means the coil is bad. Is this correct? [EDIT - THIS IS NOT THE WAY TO TEST IT--READ ON]
Thank you!
 
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Ummmmm.... 800 engine.... yep, sounds bad. The secondary windings should be 11K to 14K ohm. Not very common for an 800 coil to give up.
 
You can ground one end of a 12v test light and put the pointy end in the white wire you pull off the + side of the coil. When you spin it over like your trying to start it you should see a faint glow in the light. This confirms that the coil is getting it's signal. If it is and there is no spark it strongly suggests a bad coil.

Like the Dr said it is rare for them to fail. Usually when they do you can smell that burnt electrical smell but not always.
 
Thanks Matt and Dr. Honda. I was hoping you'd comment.
I tested the secondary coil wrong. I tested the resistance of each plug wire (ends off) to ground. Should have tested the resistance from wire to wire. Retested and got 12.74k ohm from wire to wire so I am moving on to other possible issues.

Put the test light on the white wire to the ignition coil and cranked it. No light at all, which I assume points to either the pickup coil or its bracket. That test is next.
 
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Update, and thanks so much for following along.

I moved on to the pickup coil test. Six wires come out of the magneto harness plug. Three are yellow which I assume are for charging, one is black which I assume is ground, one is black/yellow and one is yellow/white. Found this pic here on the forum (not my ski):

mag housing and pickup coil.jpg

It seems to show that the black/yellow and the yellow/white are the pickup coil wires. I don't have the test adaptor described in the manual. I verified continuity between the mag harness adaptor and the MPEM. The manual says to test the resistance between the black/yellow wire and the WHITE wire on the test harness. There are no white wires at the magneto plug. The only white wire I know of is the coil wire, so I reconnected the plug at the mag housing and decided to remotely test the resistance of the pickup coil at the other end of the wires (the rear harness plug on the MPEM).

IMG_3358.JPG

You can see where the black/yellow and where the yellow/black wires enter. They are the pins in the top row, second and third from the right in the view below. There is infinite resistance between these pins (open circuit).

IMG_3359.JPG

Wondering whether the white wire on the test harness was equivalent to the white wire at the coil, I also located that wire on this same plug. It is the top row, third from left. Again no resistance between the white wire and the black/yellow wire, regardless of whether the white wire is connected at the ignition coil or not.

The blue spade terminal in the picture is there because at the time, I wasn't sure what role the black wire played and I wanted to be able to test resistance between it and the other wires. Inserting the terminal into the plug allowed me to get at it with my multimeter, but I am now pretty sure that was not necessary.

It appears to me that the pickup coil has failed its resistance test and that the smart move would be to remove the mag housing cover and replace the pickup coil.

The other threads I've read suggest removing the exhaust pipe, jamming a chunk of wood under the front of the engine to support it, removing the front engine mount and removing the mag cover (that bottom bolt!!!). Is it possible to do this repair without removing all the oil lines and the oil pump cable from the carbs?

Thanks everyone. Hoping to be able to pay it forward someday after I get through this!
 
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...

The other threads I've read suggest removing the exhaust pipe, jamming a chunk of wood under the front of the engine to support it, removing the front engine mount and removing the mag cover (that bottom bolt!!!). Is it possible to do this repair without removing all the oil lines and the oil pump cable from the carbs?

Thanks everyone. Hoping to be able to pay it forward someday after I get through this!

Yeah you have to raise the front of engine to get at the bottom bolts of the MAG cover.

you don't HAVE to remove the oil injector lines or the pump cable (they're still attached in the picture you posted) it won't leak or anything. But I took my engine out so i dont' know if there's enough space to slide it out of your way with everything attached or not.
 
Update.
Removed the mag cover. I left the exhaust pipe in place. It blocks your view a bit but doesn't prevent access.

I did however remove the oil pump. It comes off with two socket head capscrews. Left the small lines and the control cable in place, as well as the feed line from the tank. Just swung it up and out of the way. That helped a lot.

The front engine mount has to come out in order to allow access to the bottom bolt and, to some degree, the other two in that area. I supported the front of the engine with a piece of 2X4 under the mag housing, just behind the cover.

It is hard to get a socket or a combination wrench on the bolt heads because of the paint. I used a combination wrench to get the bottom bolt. You can't see it; you have to do it by feel. It took quite a while. Two other bolts required a U-joint on the socket to get the proper angle on the wrench.

The pickup coil bracket was broken and the pickup twisted backward. I retested the pickup out of the ski and confirmed infinite resistance between the pins. I am not sure if that is correct or not. The pickup smelled burnt. I will check the new pickup to see if it also has infinite resistance.

Removing the pins from the connector was easy after I found a youtube video on assembling and disassembling Deutche connectors.

There is a lot more room to turn a ratchet if the fuel tank is moved forward. I had a bad fuel sender float and wanted to replace my oil tank grommets to take care of a tiny oil seep, so I went ahead and emptied both tanks. This provided allowed me to remove the oil tank entirely and to slide the fuel tank forward six inches. This provided more room to work, which was nice but not essential.

Getting the oil out of the tank was a miserable experience. I bought the HF transfer pump which got most of it, but the rest was still in the bottom of the tank. What a mess dealing with that last cup or so of oil. The hull is clean again now but yuck.

Pickup and tank grommets on order. I think I am out of the woods now.

I hope this post helps others who find themselves in the "no spark club" in the middle of summer.
 
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