Snowmobile World banner

2001 classic 700 backfires

3066 Views 6 Replies 3 Participants Last post by  SNORAT
My 2001 Classic 700 backfires for the first 1/2 hour of use on a cold day. Went riding yesterday at -10F and had lots of problems with backfireing at 1/4 to 1/2 throttle.  It ran OK at full throttle.  When it becomes well warmed up the backfireing only occurs a bit when slowing up from 1/2 throttle down to 1/4 throttle.  Thanks for any help.
1 - 7 of 7 Posts
fIRST OFF THIS SLED NEEDS TO BE WARMED UP REAL GOOD AS THESE ARE VERY COLD BLOODED.SECOND,GET YOUR CARBS CHECKED AND CLEANED AS I BELIEVE YOU HAVE A SLIGHT RESTRICTION IN THE PILOT SYSTEM OF THE CARBS AND IT IS RUNNING TO LEAN ON THE BOTTOM.THIS SLED HAS THE KEIHN D SLID CARBS I BELIEVE AND THESE ARE VERY PICKY TO SYNCRONIZATION AND IT TAKES A SPECIAL TOOL TO DO THIS.i WOULD SUGGEST YOU BRING IT TO A DEALER TO GAT THE CARBS CHECKED AND ADJUSTED.
</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (SNORAT @ Jan. 21 2002, 10:46pm)</td></tr><tr><td id="QUOTE">fIRST OFF THIS SLED NEEDS TO BE WARMED UP REAL GOOD AS THESE ARE VERY COLD BLOODED.SECOND,GET YOUR CARBS CHECKED AND CLEANED AS I BELIEVE YOU HAVE A SLIGHT RESTRICTION IN THE PILOT SYSTEM OF THE CARBS AND IT IS RUNNING TO LEAN ON THE BOTTOM.THIS SLED HAS THE KEIHN D SLID CARBS I BELIEVE AND THESE ARE VERY PICKY TO SYNCRONIZATION AND IT TAKES A SPECIAL TOOL TO DO THIS.i WOULD SUGGEST YOU BRING IT TO A DEALER TO GAT THE CARBS CHECKED AND ADJUSTED.[/b][/quote]
Thanks for the information.  I took my sled to the local Polaris dealer today.  He said  that they had the same problem with a 700 and it was a pinched gas line.   They are checking the charging system as it will  not start after sitting for several days. I got a new battery on warranty but I still have the same starting problems.  My sled is a good starter but you have to pull the rope to help the electric starter.
See less See more
I too have a 2001 700 Classic and I have found that you need to let it warm up far longer than you think you should have to to eliminate the backfire. I am still struggling to figure out how to get it to warm up without babying the choke and throttle for 5 minutes. My previous Polaris sleds took full choke till it started then just bump it to half choke a couple of times and you could walk away, not this one! Otherwise a great sled.
Try turning the airscrews 1/8 to 1/4 turn if this doesn't help go to the next size richer pilot jet.
I picked up my 700 classic from the local dealer today and found out that the original dealer that I got my sled from had jetted it too lean.   The original dealer had instlalled a 185 in the PTO side and a 190 in the mag side.  Stock calls for a 190 PTO side and a 195 on the mag side.  My  pilot jets are number 35 and stock calls for a 38.  The needle clip was one slot too high.  The original dealer attempted to fix a idle problem by working on the carbs and found out on a later visit that it was a bad ignition box. He never did set the carbs back to their original settings.  I am unable to go back to the dealer that I purchased the sled from as I have moved 300 miles to a new work location.  I was disapointed with my new dealer as he did not have any of the richer gets in stock so I will only be able to ride on warm days until the new gets get in.  My warranty ran out a month ago so I have to pay for all parts and labour.  My new dealer assured me that the backfire problem will go away when the new jets are  installed.  I am rather disapointed with Polaris and their dealers.  My local dealer said that an electric start 700 must be pulled over by hand on cold days before using the electic starter.  Makes me wonder why I spent the extra money on electric start as I have been having problems starting my sled when it is -10F even after installing a new battery.
See less See more
YOUR DEALER IS WRONG!! Check all the connections and make sure they are tight,also check grounds for good connection,take them apart and lightly sand them make sure there is no corrosion on anyconnections if there is clean them or lightly sand them,sand all painted sufaces were a ground cable connects after this is done apply dielectric grease to connections to keep them from coroding.If this doesn't help do a voltage drop test on the wiring and have the starter check for voltage drop under load.Yes the 700 does have pretty high compression but Polaris would not sell a starter kit if you had to pull it over by hand to start it when it was cold.I think you have a problem with dirty or corroded connections or a bad cable.Also how did you charge the battery?You can only charge it with a 1 to 1 1/2 amp charger if you charged it with a bigger charger than that you could smoke the battery.I use a trickle charger and leave it on for about 12 hours.
See less See more
1 - 7 of 7 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top