EFI “bogs down” ??

[Stiff]

Here’s the deal, I’m pretty much a novice when it comes to snowmobiles. I bought a ’93 Polaris Indy 500 EFI last year and ran without any problems. I put the sled away last March in a big barn and haven’t done anything with it until now.

It starts and idles fine, but the RPM’s won’t advance above ~4000, which is about the point the clutch engages the track.. It just kind of “bogs down”. Everything associated with the track moves freely and I’m 95% sure it’s some sort of fuel problem.

My neighbor came over to look at it yesterday. We pulled the plugs, which were a little dirty but not too bad – but they were wet, like not all the fuel was burning. We cleaned them up and dried them out with a lighter, replaced them and suddenly the sled ran great.

About an hour later it had the same symptom as earlier. I replaced the plugs with a new set, which had no effect. Today I siphoned out the old gas and replaced it with 5 gallons of fresh gas (92 octane) and half a can of Sea Foam. Same symptom.

Any suggestions??

[Ely Lake Expert]

Stiff,

I am not totally sure, but by the description you gave the problem. You may either have a loose or bad spark plug wire.

Has the machine died out or just bogged down when you hit the gas?

Ely lake expert

[Stiff]

It hasn't died. It idles fine at about 2500 RPM, increases normally to about 3500-4000 RPM, then bogs back to about the 2500 mark again.

[bluebill97]

I had the same sled 93 EFI indy 500, Is your sled bogin down once the clutch is ingaged? or before? What happend with mine is the clutch needed to be rebuilt. If you havn't had it rebuilt yet since it was new you probubly need too. expecially if you have over 5,000 miles on it. That what was wrong with mine. If you get it going on the jack stand will it seem fine after you get it going? if so its your clutch. It will run fine untill your clutch engages and then will bog down and eventually it will hit your rpm. my suggestion is to get your primary clutch rebuilt.

[Stiff]

I'll keep that in mind, but I don't think that's the problem beacuse it has this problem when it's on the jack stand. I'll be sure to remember that if I'm able to solve the problem on the stand and the problem shows up again after the track is on the ground.

[Ely Lake Expert]

Stiff,

If it didn't die out at all. I would have it checked with a spark tester. It is most likely just a bad plug wire and you are only running it on one cylinder.

Ely lake expert

[Guest]

I've used a sled like this and had problems when the battery was weak, the engine would not run right, or would not run at all.
The design of that system, performance relied solely on the battery condition. They have since changed to batteryless EFI sleds.

A buddy had the same problem a week ago with his Polaris 440 and turned out he had to thoroughly flush out the old gas. It seemed like nothing worked! I tore the carbs apart, tested everything, plenty of spark (try this in the dark and watch the plugs while pulling it over/running on one cylinder)
The plugs were always wet, but the engine ran (terribly). It seemed like nothing worked until he thoroughly cleaned out all the old fuel. Stabilize the fuel whenever in storage!

My opinion, change your fuel filter and get rid of the same gas you supposedly just replaced. Add more Sea Foam, maybe some Isopropyl too. Make sure battery is tip top. I have also had fuel pumps fail, sounds like that could be a issue too. Pull off a fuel line from the injecter and pull the engine over (with key off!) and see if gas shoots out. There needs to be a lot of pressure to keep the fuel flowing.

[This message has been edited by CD (edited 01-27-2003).]

[Stiff]

You may have hit the nail on the head!! I just put a new battery in too. It's new, but I know it wasn't well charged. (I actually started the sled with the charger on the battery) I put a trickle charger on it last night before I went to bed. I'll be very curious if that may solve the problem on it's own. I'm guessing it will be a good idea to replace the filter just as a matter of course.

Thanks for the input! I feel somewhat less lost, or as least less alone. I wish I understood the whole fuel injection system better.

[Stiff]

CD,
You nailed it! I had actually bought a new battery, but I still had the old one installed. I charged the new one with a trickle charger overnight and just put in after work tonight. Everything seems to be working perfectly.

Thanks very much for the advice,

Stiff

PS – I wonder if you could use a vexilar battery to get yourself out of a jam if this happened in the middle of nowhere???

[Guest]

Cool! Hope the snow comes so we can enjoy some trail riding for once. It wouldn't be a bad idea to slowly charge that battery after every use. I know it sounds corny, but that's the old EFI systems for ya.

[Rtrouter]

Yes you can use a vexilar or flasher battery to get yourself out of a jam. I did it 2 yrs ago on leech. I was very relieved to have it.

[Stiff]

Nice! Let's hope none of us ever gets in that jam again, but keep it in mind just in case.

[pikechaser]

put a cat engine under the hood with efi & see what youve been missing