Hello and 71 Panther Ignition problem - stumped - Snowmobile Forum: Your #1 Snowmobile Forum

DukeOfEarl · 11-22-2012, 06:11 AM

Hello all, DukeOfEarl here. I just wanted to introduce myself and ask a question.

Use to ride a lot back in the late 70's to mid 80's and them got back into it for a few years in the late 90's. Now with the kids getting of age it is time to start all over.

Anyway we have a 71 Panther 399 Kohler with a parts sled to match. The better sled has a spark issue that I was hoping to get some help with. Here is the situation... Cylinder 1 has good spark and the engine will run on it, at least briefly. However cylinder 2 has no spark. I did the swap the plug and wire thing and that didn't work. I then checked to see if the coil on cylinder 2 had power coming to it through the blue wire and it did. So I then installed coil pack from the parts machine(as that was easier than just changing the one coil) and ended up with the same issue. So then we took the two apparently good coils and put them on the same pack and installed them. The issue remained, cylinder 1 good spark, cylinder 2 no spark. So I have power to the coil, a good coil, a good wire and yet no spark.

My only thought is that the power coming from the engine is not strong enough to make the coil fire.. Does that make sense? Should I dig in an clean the points? I guess I could use the blue wire from cylinder 1 on coil 2 and see what happens? Any thoughts...

**RJ Gleason** · 11-22-2012, 09:32 AM

No, you couldn't do that as the spark would be 180 out of time.

You need to go into the points and make sure that the contacts are clean and the condensers are good. Clean up the magnets while you have the flywheel off too.
Clean the ends of the charge coils as well.

DukeOfEarl · 11-22-2012, 10:21 AM

Quote:

Originally Posted by RJ Gleason

No, you couldn't do that as the spark would be 180 out of time.

You need to go into the points and make sure that the contacts are clean and the condensers are good. Clean up the magnets while you have the flywheel off too.
Clean the ends of the charge coils as well.

Thanks for the info RJ. I guess I should have clarified that a bit with the blue wire. I only wanted to test the amount of spark by using the wrong blue wire, not to leave it that way. Sorry about that. Anyway since my first post I did momentarily swap the blue wire and it did fire cylinder 2. Not sure if that is good or bad news.

So now I have removed the flywheel and cleaned the points, magnetos, and all the other stuff in there. Put it back together and still nothing on cylinder 2. I guess the next step is to get new points and condensor for the bad cylinder. Not sure which is the bad set, but I could always change both.
Any other thoughts?

**RJ Gleason** · 11-22-2012, 12:55 PM

Best to do them as a pair, less likely that the other will fail then.

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SB49 · 11-23-2012, 07:56 AM

Can you swap points and condenser out of donor sled likely they are OEM parts and better than any aftermarket stuff you can get. Did you check all the wires and grounds for cracks or breaks in the insulation. My 399 rotax had intermittent spark in one cylinder once couldn't figure it out till I tried messing with it in the dark garage and found a spark arching from the i thought good ignition wires to the block.

DukeOfEarl · 11-24-2012, 08:33 PM

I was able to get one set of points and condensor from the local shop. I put them in the bad side and still have the same trouble. I did ground the coil with a jumper wire so I think the ground is fine. Getting really flustered with this thing.

I guess the next step is to change the internal coils (the copper wire things)?

**smallengineguy** · 11-25-2012, 06:39 AM

I wish they made electronic ignition conversion kits for snowmobiles like they do for lawn and garden engines. If you put new points/condenser in, the only thing left is the internal coil.

80lectro · 11-25-2012, 12:48 PM

Do you have a diagram of the stator? If its anything close to the rotax stator design, both condensers charge off the same primary coil on the stator plate. Hence, if one side fires, the other should as well. I would check for a break in the insulation of the coil feed wire. And, it may sound crazy I had a similar problem on my rotax 503. Ended up being a short @the ring lug that connected the condenser wire too the insulated stud on the breaker point. Once the lug was bent away from contacting the mount for the points, she fired right up. Good luck!
-Nick

SB49 · 11-25-2012, 07:28 PM

I agree with Nick should be two coils. Primary for ignition and lighting for accessories. If you have three then there may be two separate coils for the ignition.

Old Man · 11-25-2012, 08:11 PM

Here's a link for the pre 73 Kohler motors. Section 3 has some info on the ignition system and trouble shooting. Hope this helps.

http://www.vintagesnow.com/Engine_ma...woStrokeSM.pdf

**RJ Gleason** · 11-26-2012, 07:36 AM

There are three coils, two for ignition and one for lights.
The ignition charge coils will be stacked as a pair. It is very likely that one is shorted out and that is why you do not have any spark.

80lectro · 11-26-2012, 12:21 PM

Again, going back to a rotax style stator plate...
there are indeed three coils on the stator (agreeing with RJ) however... only ONE coil charges the condensors, the other two provide AC current to the voltage regulator. Again, would have to find a diagram for your stator, but cant imagine it being too different. The ignition system is more of an RF design than standard electrical thinking. Each cond. Is attached to opposite sides of the coil, charging while the points are closed. When the points open, the discharge from the cond. Looks for the shortest path to ground, thus bein the gap in the spark plug. In effect, both condensors are sometime charging at the same time!

I know its confusing, but hey, it works!
-Nick

**RJ Gleason** · 11-26-2012, 01:49 PM

But, not on the Kawi stator.

Old Man · 11-27-2012, 06:42 PM

What's below is copied direct from the Kohler Service manual. My guess is that the OP's 399 Kohler has the two primary (ie. exciter coils) and that one of them is faulty. He can tell if it has a single or a double by examining the color of the leads as mentioned below.

"FLYWHEEL-MAGNETO IGNITION
Two types of flywheel-magneto ignition systems are used. One type has 2 primary (low tension) ignition coils on the stator while the other type uses a single primary ignition coil. Both systems have 2 external high tension coils--one for each spark plug. Without actually checking the stator to see if it has single or double primary coils, the only way to tell which system is used is by checking the color of the ignition leads off the primary coil or coils. If a solid blue lead and a blue-white are found, the system is the two primary coil type. The two ignition leads are color coded solid blue and blue-red on the single primary coil system."

DukeOfEarl · 12-14-2012, 12:10 AM

Well, I finally got it. Turns out I am an idiot. When I replaced the the points and condensor for cylinder two, some of the black wire was grounding out the condensor so it would never charge.

There are three inner coils on the machine, one is for lights and the others are for each of the cylinders. These two are stacked on top of each other on the same side of the stator plate. Note the pic below...

An interesting thing happened when working on this. I have a parts sled which is identical except for the parts sled has electric start and a speedometer. They were purchased together by the originals owners from the same dealer. However when I went to change the side cover which holds the stator plate (so I could just use the one from the parts machine without having to change anything else, points, cond, inner coils etc) it did not fit, the center flange was two big. I couldn't believe it. Take a look at the picks below...