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Discussion Starter #1
Ok to start off Im new to this all and just got 2 sleds (cheap)
1st is a 81 Indi 340 540 miles
2nd is a 84 Indi 600 1500 miles

Both of them haven't been run in 2 years.

To start off I've replaced all the gas lines, put new gas in, and cleaned the carbs, 5 total between the 2 sleds, put in new plugs and replaced the pull rope on the 340 (hope I don't have to do that too much!)

They are running well after I get them up to about 2500 rpms, but they just won't idle. I'm no carb man, so is there any good advice short of taking them to the shop for work that anyone could sugest? Oh, on the 340 the only way to start it is to put it full choke till it turns over and then no choke and hold down the throttle. Usually after 2 pulls the 340 starts, and the same for the 600.

Everything else seems to be doing great.



Ok I went back into the carbs on the 340 and spent special time with the pilot jets and yaaa they were crudy cleaned them out and put every thing back together and man she has a nice idle. one down and one to go now to go after the 600 and 3 more carbs but what a pay off thats been the only thing that was wrong with these sleds
 

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sounds like on the 340 the carsb are outta synch...i had the same problems wrong with my ext wouldnt stay idling...im not much of a carb man but taking what has happened to me in the past and by what ur explaining sounds much the same

Duct tape the only real solution
 

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Well if you cleaned the carbs a couple of times, I'm sure you have them spotless. Just make sure that the pilot jet is not plugged. The pilot jet is located in the bottom of the carb, inside the small round hole or tunnel facing the engine. If you take the float bowl off, look for it in front of the main jet. You can take out the pilot jet with a small slotted screwdriver. This hole in this sucker is super small and will definitely affect your idle. But, it could also be your fuel pump. If your carbs were really gummed up and the sled has been sitting a while, you pump could be gummed up too. Check the vaccuum line and fuel lines also, it cant hurt. Good luck.

'HAMMER DOWN !!'
 

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Well i would check the syncronization of the carbs, and if that doesnt help any, wait for some colder weather. I know some sleds especially older ones dont run to well in the warmer weather. As was already said, make sure your pilot jet is clean, and also make sure your needles and seats are sealing good. Make sure the air screw is out 1 and 1/2 turns on each carb and check to make sure the idle screws are adjusted identicle. I made a vac gauge out of some primer line and a peice of cardboard that someone on here found on another site. It worked really well and except for the cost of about 8 feet of primer line it was free.

Polaris is my way out - Other people just use a door.
 

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It could be a number of things. I agree with May that it could be the fuel pump. I had a similar prob to what you're describing on a 76 Liquifire with dual carbs and I changed the fuel pump with another I had on hand ( or you might want to get a cheap pump repair kit.) and that solved the problem instantly. Oil can build up on the diaphram and problems develop from sitting too long. Also check a service manual to see where your idle screw needs to be set. Most are usually 1 1/2 turns out. Also check choke cable settings and throttle cable settings, these can get ya too. If you have questions on that stuff I can maybe send you a scanned pic of how-to.

Check the color of the spark plugs too.

Good luck!
 

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Go to the Mikuni website (below) and find your carbs and download the super tuning manual for them, it's real easy to read and understand.
General idle problems start at the pilot jet and needle and seat, I would adjust those before replacing or rebuilding fuel pumps.
If those sleds are oil injected you will want to make sure the oil pump is working OK....pull the plugs, unplug an oil line from the manifold and have someone pull her over and watch for oil to come out....very slowly mind you.
A 2 stroke should idle in warm or cold weather.

http://www.mikuni.com/fs-carburetor.html

When hell freezes over, we'll ride there too.
 

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The first thing I would purchase is the shop manual for those sleds. These manuals are loaded with everything your heart desires. I picked one up from Ski-doo, specific for my sled, and it was well worth the $50.

Ski-doo goes into good detail regarding troubleshooting and tuning/syncing the carbs (and the rest of the sled as well). I assume Polaris will too.
 

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Discussion Starter #8
thanks every one im going to look at the jets again to se if i missed something the website that had the manuals helps alot


Hope to se every one on the trail
 

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81 indy 340?? same motor as my TXL 340. Had the same prob on that sled during warmer days. couldnt get anything ABOVE 3000rpm till it was below 45 degrees. those motors are picky but ill tell you one thing. Be prepared to have that sled for life cuz those 340's never die and run fast as hell.. now the Indy 600..... I have an 83 indy 600 with a big bore kit triple decker pipes big bore carbs etc etc.... 84 was the first year for oil injection on those sleds i believe.stock jet size for those carbs are 250 mikuni mains. needle jets i cant think of off hand. while you have the carbs apart replace the needles and seats. that motor in your sled is VERY picky when it comes to temps. personally i would reccomend rejetting to a 260 mian jet as that motor will need it.if you need any other help ill help as i can Just PM me and ill do what i can. Or if ya have MSN Messenger IM me at [email protected]



Bobby
My wife said its Her or the sleds........ I'm sure gonna miss her

Stop Inbreeding....... Ban country Music
 
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