My 670 does not like to start very well when she's warm. Usually, if I don't give a little bit of thorttle, she won't go. If I just pull the rope, sometimes it will start but barely idle. I have heard that some of the "older" sleds (90's) are tough to start that way.
* * * Is there a fix for it or do I just have to give it a bit of gas every time? http://www.snowmobileworld.com/forums/iB_html/non-cgi/emoticons/confused.gif

I have a 97' mxz 670 that does the same thing. *It starts better when it is cold than when it is hot. *All I know to do is sit on your seat, give about 1/4 throttle with one hand and pull with the other hand. *I would also like to read sugestions on how to fix this. http://www.snowmobileworld.com/forums/iB_html/non-cgi/emoticons/wink.gif

The idle circuit is too rich, back out the mixture screw a turn, technically they say a quarter at a time but you`ll probably wind up a turn out.

which one is the mixture screw? How will that affect the cold start because these sleds have a lean condition warming up?

Rocketman: One of the main causes could be wear on the crankcase at the R.V. openings. As these motors get older is becomes more of a problem. As you pull the engine over it has very little vacuum signal to pull fuel in to start, thats why all of the R.V. engines have primers and not enrichment valves. Dino http://www.snowmobileworld.com/forums/iB_html/non-cgi/emoticons/wink.gif

For whatever reason, my '00 700 MXZ with DPM was the same way. If it was warm, you'd have to give it a little throttle to start it. The '01 800 seems to be OK in this regard.

dino...where would this wear occur? Behind the rotary valve?

My 00' MXZ 700 W/DPM *has the same problem also. It starts cold on the 2nd or 3rd pull everytime, but when it's warm it sometimes takes about 4. I find that holding the throttle open a hair helps though.

I have a 2000 MXZ 700 with the same problem. *I crack my throttle 1/2 open and pull. *It starts on the first pull everytime. *Cold starts, second to third time. *Most of the series 3 motors are like this.

Rocketman : Yes behind the R.V., As the motor sucks it a fresh charge, it also tries to suck in the R.V. as well and it wears just above the mag port and below the pto port. Skidoo changed the design back a few years ago to prevent this and from what I see it helped. Dino http://www.snowmobileworld.com/forums/iB_html/non-cgi/emoticons/confused.gif

Oh...mine starts well cold...if I prime it right! http://www.snowmobileworld.com/forums/iB_html/non-cgi/emoticons/wow.gif *I think I've cracked the code. I can get it to start 1st pull in the morning at -25C most times. http://www.snowmobileworld.com/forums/iB_html/non-cgi/emoticons/biggrin.gif