Just came in from driving today when the engine was dying down, indicating it was low on fuel. Switched to reserve after engine stalled, but has not started. Only fired a couple of times. Looked and sure enough its down to the last gallon of gas. Already been running with gas treatment added to the gasoline. Previous time I switched over to reserve(in the fall), it continued to run without ever stalling. Course, it's been much colder now here in OH and have been leaving it in an unheated barn at a friends who let's me ride there.

Questions:
1)Could water in gas be causing this? [I would doubt it, since it's been running fine, until I ran out of fuel today]

2)Could reserve line be plugged? [Doesn't appear to have a pinch or be twisted.]

3)Is it possible I flooded the engine while trying to start it back up?

4)If you do let the engine run completely out of gas, before switching over to reserve, is it possible there's an air pocket or something else preventing the fuel to flow from the reserve into the carb?

Any ideas or thoughts would be greately appreciated.

 

On a weekend ride last summer my Scrambler ran out of gas on the trail. I switched to reserve, fired it up and kept going. Next day, same symptom, but only fired back up for a minute then died. Ended up being a fouled plug. You might try a new plug.

 

AKScrambler
Thank-you for your response. Dumb question on my part, please forgive me, but is there usually a spare plug in the tool kit when you buy your machine? My HO only has about 100 miles on it and don't recall if it does.

 

Water is heavier than gasoline; could have settled to the reserve portion of your tank.

If your fuel system is contiminated by condensation, you should drain your carburetor float bowl before adding fresh dry gas.

Diogenes

 

No, there's not usually a plug in there. When you go to get a new plug (or 2) I would recommend NGK plugs. I think most would agree. I bought a plastic "spare plug holder" to keep with me on rides. Actually, this may or may not be your problem though. It's really a more common problem with 2 strokes. But it's an easy check and if it's not the case, you will have a spare plug for when it does happen. Wish I could be of more help.

 

My mechanic friend told me awhile ago that if you never use reserve, or use it often, that dirt, water, or other contaminants settle to the bottom of the tank and sit by the reserve line. Then, when you do use it, all that stuff gets sucked down the line and into the filter or carb, clogging it. Hope this helps.

 

AKScrambler you hit the nail on the head! Put in a new plug and it fired right up. Checked the odometer and my HO actually has 78 miles on it. Only had two full tanks of gas in it thus far and each tank had some fuel additive included.

Now, I'm really scratchin my head.

Questions:
How does this fouling happen?

1)Poor gas (always run 87 octane), even with fuel additive?

2)Poor starting habits? [I rarely ever use the choke and when I do, I only have to pull it out half-way.]

3)4-strokes have a habit of fouling plugs quite easily?

4)Not opening the engine up enough? [rarely get it going over 25 mph - mainly trail ride]

5)Running the tank too low in the cold weather and leaving it sit in an unheated barn (before refueling), thus creating more moisture in the gas?

6)Is it best to try and switch over to reserve ASAP, before the engine dies out?


I don't get it. Please enlighten me with all your years of experience, guys/gals. This is my first atv. I certainly wouldn't want my wife in this predicament if she was riding alone. I NOW am carrying an extra plug with me, but I doubt in a hundred years my wife could ever change a plug on our HO.

This incident sure brings up the point many others have made, that Polaris should really have a fuel guage on their gas cap. Makes so much sense.

 

more then likely just a bad plug don,t sweat it I have never replaced a plug on a 4stroke machine in 4 years and that was a total of 5 sp 500s and 1 400 scrambler. But ut never hurts to carry a spare.

 

I agree with Dazed. It's pretty rare for a 4-stroke to foul a plug. The only exception to that I've ever seen is when there is engine damage. (Like when the wife puts KEROSENE in the lawnmower. I have to change the plug everytime I cut the grass). But I wouldn't worry about that. Just a FAILED spark plug.

Dave

 

Well, I'm glad that's all it was. However, I agree with the others. A 4 stroke shouldn't be fouling plugs much. On a 2 stroke, riding slow a lot will do it. You probably did just have a dud plug. Polaris does (or has) put gas gauges on some of the machines. I know the Sportsmans used to come with them. I'm sure your dealer will sell you one. I really don't think it matters how quick you switch to reserve. Usually by the time you realize you're running out of gas you've stalled anyway. After the first few times this happens you'll be able to make the switch and restart before your wheels stop turning. Kind of tricky on my Scrambler. (valve is inside the front fender)