VintageVmax.com

Hello, I recently acquired an 83 vmax 540 in really good shape for free, but it has been laid up for the last 10 years.

It had spark and wouldn't fire so I cleaned out the carbs. After pulling this thing over a million times and getting nothing more that an occasional backfire I decided to take a closer look at the spark.

I turned the crank over with a heavy duty drill with the plugs laying on the head and noticed the spark is healthy and blue at low speeds. The drill has a variable trigger so you can see where it comes and goes. There is only a very small rev range in which it sparks.

Things I have done already:
Replaced Coil
Ohm'd out the stator windings (charging and pickup coils), passed tests
Checked wiring harness and wire continuity
Unplugged engine stop and key and
Unplugged black wire on CDI, no change

I am assuming it is the CDI box but they are pretty expensive on ebay..

As far as I know this sled ran when it was parked.

I went to go pull the stator apart but it looks like you need to pull the engine out to get a puller on it.

Before I do this over something trivial, I would like advice from someone who might be familiar with this.

Appreciate any help,
Thanks, Clayton

First, tell us where your from, maybe someone with a good box lives somewhere near you. That worked out well for me with a ArticCat issue

Near the twin cities in Minnesota.

CL4 Welcome to V.V. !

Try...
viewtopic.php?f=2&t=1529
No Spark
Two different circuits. One for lights, and one to the CDI for spark. Check the CDI for a single black wire. Disconnect this and see if you have spark. If so, the problem is in your kill switches, ignition switches, connections or wiring harness somewhere. If still no spark, check your CDI, Coils, or magneto. Be careful when checking for spark by disconnecting the black wire, as there will be no way to kill the engine if it happens to start.
These have a history of the stator "imbedded" (mounted permanently) pulser coils losing contact thru thermal expansion. Sometimes engine heat makes it quit after a few minutes and I've heard of a few that due to how these particular ones became "disabled" (lost pulser ground to stator mounting plate)

Thanks, I have tried those things. The only thing I haven't done is visually checked the stator because it seems I need a puller to get it off and I'm not sure I can do that without pulling the motor. I did however ohm out the windings and they passed.

I did mine by loosening everything up them just lifting up the right side and putting a block under it. Didn't have to deal with clutch and wiring, don't think I even drained water, it was a few years ago.

I found a used box locally on Craigslist that "works" for 75 bucks.
Will post the results..

This new unit has zero spark...

Good.. and bad news.

How in he heck does this happen?

Does anybody have one laying around?

Would rather buy from here than ebay.

Thank you