problem with sled

[summit x 670]

hi i have a 1999 summit x 670 and the sled when i first take off from the truck runs great and then will bogg down then run great and then bogg down it sounds as if i am hitting the kill switch and then releasing. it also has been fowling plugs in the left cilinder and the right cylinders plug is white when i pull it out any sugestions would be much appreciated

 

[99summitx]

First off welcome to the site. Have you pulled the carbs off yet and cleaned them ? Could be plugged up jets, needle and seat also check clips are still attached on top of throttle needle. If you need any spec # for carb setting let me know. I'm sure you'll get more suggestions ....hey Summitric

 

[summit x 670]

no i haven't tried that stuff i am not very mechanicaly inclined when it comes to snowmobiles but what i don't get is why it runs fine after about 15 minutes of riding i was wondering if it is something wrong with the dpm

 

[Summiteer]

White plugs are bad, sounds like you need to get your carbs cleaned, maybe check the rubber boots between carb and engine for cracks.

 

[milton]

Had a rm 125 a long time ago and had the same problem. Re did the whole top end and the works over the winter. Took it out in the spring and the same thing. Someone told me to check the needle and seat and the problem the whole time was the clip on the top of needle was off and laying in the top of the carb. Clip it back on and a way we went. Just something to try.

 

[summit x 670]

hey thanx for all the helpful info this is the best site i have found for help i appreciate it greatly

 

[DRD]

For the bogging issue, you need new solid top plugs and new caps, maybe wires. My 99 would always do this, the arcing in the plugs would mess with it's tiny electronic brain. The white plug is a different issue IMO.

 

[Modman]

For the bogging issue, you need new solid top plugs and new caps, maybe wires. My 99 would always do this, the arcing in the plugs would mess with it's tiny electronic brain. The white plug is a different issue IMO.

I run the screw cap plugs on my 670 and no problems. I think the bogging and white plugs are related, sounds like it is lean on the bottom end? White plugs are only good if you are running av gas because it burns them white, on reg fuel it means it is lean. Air screw hole could be plugged, pilot jet could be plugged, needle jet and jet needle could be too lean, c-clip could be in top position, slide cut-away could be wrong, carbs may not be sync'd, venting might be wrong, air leak in one cylinder....

Something is not right with the carbs would be my guess, since you're fouling on one side and lean on the other (unless you have an air leak in the motor somewhere). 99summitx suggestion is bang on IMO, pull carbs and check specs on all components and give a thorough cleaning, clean all jets and passages. While they are soaking or drying, check timing at TDC and then confirm that you have a good spark on both cylinders. Then I would check hoses to DPM at the same time. Let us know how it goes.

 

[DRD]

If it's a true "bog" then it might be carbs. If it's cutting out like someone's hitting the kill switch, try the plugs/caps. Does it cure itself after a while or a few miles down the road?

I could never run screw top plugs and I had to make sure the caps were in good condition or my 99X would do the same thing (cut out) without fail.

 

[magnet]

mine does the exact same thing until warms up. i think dpm related myself. as soon as it warms runs good. but my plugs aren't fouling or going white. just kiss the hood once in a while:d:d if you find out what it is for sure pm me please.

 

[summit x 670]

thanx for all he info guys i actually ended up having somebody offer to buy it for enough that i couldn't turn them down so i told them to let me know if they figured out what it was. so now i am looking for a new sled any suggestions on what kind of good used sled to buy