Fowling Plugs

[Bandit]

I have an 04 Ski Doo 600HO SDI that has about 250 miles on it. Bought new last year. It ran perfect the first 150 miles, but in the last 100 it has fouled the plugs 3 times, and won't start. It only idles long enough to warm up before ridden. It has electronic reverse and the first time it fowled them was going from reverse to forward. The last two times my kid was riding it and I am not sure when it happened, but he said he did not put it in reverse. Any ideas??

[Macgyver55]

250 miles on an 04? Sounds like a fuel problem. Thats basically not even 3 tanks of gas, or a good days ride. Is the gas in the tank new? If not, get rid of that first and put some fresh stuff in. Then maybe a small amount of injector cleaner and a good "spirited ride"! 2 stroke motors run best when "aired out" a bit. I don't mean you have to ride like a nut, but just get it up to operating speed and temerature for a while each time you run it. Prolonged use at low RPM or speed is a recipe for problems. My 600HO is a carbureted and I have 7000 miles on it now with the original plugs. Let us know what you find.....

[Bandit]

I was thinking that the gas was fresh, but I guess it never has been run very empty so it probably does have some of last years left in it. I run 92 octane and and added seafoam for summer storage. Ran it a couple of times this summer for a few minutes each. Was the seafoam a good idea, or should I use something else? It gets rode fairly hard[on the river]. It only has 250 miles on it cause it was bought new last winter. It was a carry over with 0 miles, and ya..... we don't ride much. I have a 99 carburated 600 and it runs great. I will run her about out of fuel, start fresh and see what happens. Thanks Macgyver! Don't work too hard.

[Bandit]

Jeeze I must be dumb. Not only don't I know anything about sleds, I can't spell either. Maybe if I titled this fouling plugs instead of "fowling plugs" you guys wouldn't think I was talking about my favorite goose gun.

[lawdog]

Bandit why the 92 octane? Most manufacturers don't recommend that and you should run what they recommend. Straight 87 non-ethanol is all I run in all my small engines...

[Bandit]

I guess I run that in everything, I figured the higher the octane the better. Looks like I better do some research.

[Bandit]

O.K. Ski Doo says I can run super unleaded min 91 oct, or reg unleaded min 87 oct, So I should be O.K. there.

[ChuckN]

Is it minimum 91 octane or minimum 87? Some high performance engines require 91 octane minimum. Some operate 87 minimum, but not necessarily both as "minimums".

My Cat is recommended (designed) to run on 87 octane/10% ethanol. I ran 92 in it and it ran terrible. Hard starting, engine would not idle well, loss of performance, mileage, etc..

I too would seriously look at the fuel in the tank and get fresh gas in there like Macgyver said. You should not be blowing plugs like that. May want to check compression just to know, I've had plugs foul and I found poor compression. That's the worst scenario, but happens...

[Bandit]

[is it minimum 91 octane or minimum 87? Some high performance engines require 91 octane minimum. Some operate 87 minimum, but not necessarily both as "minimums".]

I don't know, that is just what Ski Doo's HSOforum said for an 04 600 SDI.

Apparently it can make a big difference. So the first thing I am going to do is get the 92 out of it and try 87 like you guys say. Chances are that is exactly what is wrong with it. I never would have thought that running higher octane gas would hurt anything. Thanks again guys. I should have time to get this done Mon or Tues. Will let you know how it turns out.

[Eyewitness]

Bandit, one thing you may want to do is relube your ECM module connectors. I had a similar problem with my Doo and the dealer turned me on to this issue which was a simple fix. The ECMs on all the new machines are extremely sensitive to voltage drop. After the connectors are anywhere from 2-4 years old they will start to dry up. What I mean by this is that they come from the factory with special grease that allows for no voltage drop across the connectors. As this grease starts to dry up it takes more and more voltage to make that connection. These new control modules (ECMs)are so sensitive to voltage drop that they will start to act up. Mine would start fine and then run like the carbs were all whacked out and the plugs were fouling. The warmer it got the worse it got. This didn't creep up on me, it just started to happen all the sudden after it was running fine.

The fact that it is new doesn't really weigh in too much here as it is an 04' and so has been sitting for 4 years since it was built. Even if it isn't your cure, I would do this anyway. It is simple. You will need to go to your local auto parts store and pick up the following for about $7.00. A small tube of dialectric grease and a small spray can of dialectric cleaner/dryer. Just pull the connectors apart (should be two) and spray into the female side holes really well with the cleaner/dryer, then do the male ends. Walk away for about 1/2 hour or so to make sure they have had a chance to dry real well (no residue) and then take your dialectric grease and fill the female connector holes. Plug together and wipe off any excess and away you go (hopefully).....

The fact that you have only 250 miles tells me that you have not run much gas through the tank. Hopefully you topped your tank off and put in some stabil and ran through through the carbs prior to summer storage. Do that one thing and she should fire right up every time.....Hope this helps.

[Bandit]

Thanks, I should have some time to look at it tomorrow. I will take care of the ECM connectors when I change the fuel. I did top off the tank and added sea foam and ran it before I parked it for the summer.

[Dozer]

Ive had a problem with too much sea foam wrecking plugs. If it is mixed too strong its not good. I would fill it up with gas to dilute it down. Ive never heard of anything running worse on premium. You will get more power if you run whatever the engine is desighned for but I can see premium making it run that bad. They post with an artic cat running bad is probly because there is a wire that you leave hooked up for ethanol and unplug for nonethanol.

[Bandit]

Well guys, I pulled it in the garage last week and went though all of your suggestions. Changed the gas[92 to 87 oct fresh], added some injector cleaner, cleaned and lubed the ECM connectors. Anyway, I thought everything looked good, Told my boy to take it for a ride and check it out. He has put about 300 miles on it since without a problem!!! Thanks alot guys, for the help, you're great!! Since I did everything at once, I am not sure what took care of the problem, but something sure helped.