SL650 Runs then dies

[Scoundralzzz]

My Polaris 650 has been in the shop for over a month now. The manifold has been machined and put back together. Ski ran for 2 hours then no spark after that. Tested and stator bad. Bought and replaced the stator and boat started right up and ran for 20 minutes great and died with no spark again. Stator checks great. CDI checks good. Fuel take-up checks fine as Polaris said there was a switch for killing engine with low fuel. Still no spark. What can I be missing. This is why it's been in the shop in the first place. Would run for a while great, then poof, no spark. Need quick help as I'm trying to get this running before Friday as we are leaving for vacation on Saturday. Thanks for quick ideas.

[K447]

How did you check the CDI?

Have you disconnected and cleaned up all the connections in the electrical box, especially the critical ground screw where several items are connected together?

Checked all the ignition coils for correct resistance and solid connections, individually?

[Scoundralzzz]

Yep, and Yep.

Coils all look good and rechecked all grounds and connections in CDI. Still no spark.

[K447]

...CDI checks good...

How did you check the CDI?...

Why are you sure the CDI is not the source of the problem?

[Scoundralzzz]

I'm not. The mechanic I have fixing this thing said the CDI was not the problem as I asked the same thing. He said he tested it and it was fine. How he did that I don't know. Is there a way to see whether it is the CDI or not? The reason the ski was originally fixed was because there was an internal water leak. It was always a high humidity-type environment. I felt the CDI would have been affected, but he told me it was a sealed unit and couldn't be the problem. I am pasting all responses I get directly to him because he's lost at this point. I feel it's got to be some intermittent type ground problem, but he can't find one. I sent him your last response and also a thread I found on a SL750 that seemed to be very similar. I'm really just praying something helps him find the problem in time.

It is a very intermittent problem. One time it may run for hours, then the next time die in 10-20 minutes with no spark whatsoever. When it runs, it runs full out with no hesitation.

[K447]

Intermittent electrical problems can be a bear to nail down.

If possible, try using another CDI, even if it is from a slightly different model.

Even if you have to buy a used one for the testing, if your CDI is actually good, you should be able to then re-sell the purchased CDI for similar money, so not a big cost to you. If your CDI is bad, then you need the replacement anyway.

If the problem doesn't appear with a substituted CDI, then your CDI is the culprit.

You really need to be able to jump on it with a multi-meter when the problem arises. If it is heat or vibration caused, and it fixes itself while sitting, you really need to be able to check lots of things in a hurry when it dies.

[Scoundralzzz]

It's funny you say that. He has another 650 with a similar problem and he bought another CDI box for it, but says neither one are the same as the one in my ski. He says they are the same year, but different ignition system. I was hoping he could test the other CDI to see if mine failed or not. NO JOY again. I don't think I have much of a prayer of this joining us on vacation this year.

[xlint89]

It's possible the kill switch is grounding out. Ask him to remove the blak/yel wire from the circuit board and try starting it.

What CDI is he using? A 650 stator has an analog signal that will not work with a 750 CDI. A 750 and 780 both use a digital signal stator.

Did he re-use your flywheel? There are differences between the flywheels of a 650 and 750/780 as well.

[Scoundralzzz]

Xlint,

He is using the CDI that is in my ski. The others are obviously the different type and he isn't putting one of them in mine. The flywheel has not been changed either.

As for the ground on the kill switch, I will pass that along to him. He told me in an email this morning that he has changed grounds all over the place thinking pretty much the same thing as most, that there is a bad or intermittant ground somewhere. He even had a former Polaris mechanic over and neither of them can figure this one out. So at this point, crazy ideas may not seem too crazy to us.

[xlint89]

The stator was replaced. What was the part # used to replace the old one?

What is the part # of the CDI being used presently?