2007 Arctic Cat M8 hard to start when cold.

[Coffeeaddict]

I am new to sledding (15 yrs old) . . . I just got my own 2007 Arctic Cat M8 and am very happy with it! The only issue so far is on a cold start. When the machine is cold (even at outside temps of 70ºF) it takes aboutnten pulls to fire up. At about 7 pulls, it will try to start but sputters out. . . . It does this for a couple pulls and then finally starts and runs well. After its been started up and is shut down . . . . only takes one pull to start from then on. Can't imagine how much harder it will be on the mountain at zero degrees! The plugs have been changed with new . . .don't know what else to try. Anyone have any ideas? Thanks.

 

[Coldfinger]

Not sure, but try holding the throttle lever open while trying to pull start. Sometimes when my 10 M8 wont start I do that and it takes right off. Make sure to have your brake set before starting in case it starts quickly.

 

[Wheatie]

I have an 09 800 that I had one year now. Out of the blue one trip last season we shut it down, rested a bit and to our surprise it would not fire. After 30 minutes of wiggling wires and such we were just about going to tow it and one more try I decided to depress throttle a bit an fired right up.


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[greenmtnboys]

Try just opening the throttle a little and pulling it over if the throttle cables are too tight it could activate your throttle override switch.My sons did this and it would happen intermittently.We ended up disconnecting it but I don't recommend that as it is a safety switch.

 

[Old & slow]

I am new to sledding (15 yrs old) . . . I just got my own 2007 Arctic Cat M8 and am very happy with it! The only issue so far is on a cold start. When the machine is cold (even at outside temps of 70ºF) it takes aboutnten pulls to fire up. At about 7 pulls, it will try to start but sputters out. . . . It does this for a couple pulls and then finally starts and runs well. After its been started up and is shut down . . . . only takes one pull to start from then on. Can't imagine how much harder it will be on the mountain at zero degrees! The plugs have been changed with new . . .don't know what else to try. Anyone have any ideas? Thanks.

The way you are describing the issue it makes me think you aren't getting fuel right away. This could be numerous issues but start with the cheap easy stuff first. I would start with checking the fuel pickups, make sure they are clean the hoses look good and are working right. Make sure the fuel tank is clean inside no debris or something floating around. Then try fresh fuel with some Seafoam added run it for a bit to get the seafoam through out the system. Make sure the throttle cable is adjusted correctly. See if that make a difference. If you still have a starting issue I would check the fuel pump for pressure see if it is within specs. The sled should start within 2 or 3 pulls. If you go the Country Cat they have service manuals for that machine that may also be helpful. Good luck!

 

[MI1M600EFI]

My current M8 has a stator that's a bit weak. It also doesn't like to start when cold, and occasionally won't restart when it's good and hot. To confirm, you can run the pump for a few seconds off a 9v battery. It'll build pressure in the rail, and then it should start easily. If the stator is weak, the pump won't run enough to get it running unless you really rip it over. Unfortunately, that's hard to do when it's cold. Even at 70F mine takes a manly couple of tugs to get it to fire... At 15F, I've had to heat the engine with a torch to get it to pull over fast enough to start... My other M8 usually started on the second pull, and I din't have to yank nearly as hard on it...
Good luck!!

 

[Coffeeaddict]

Thank you all for your help! It was much appreciated! Unfortunately I am only now getting to work on my sled, darn school always gets in the way... I tried the fuel pump with the 9v battery and I did hear the fuel pump, but it didn't change anything on start up. Does the polarity matter? I connected the 9v battery to the red lead on the fuel pump, there is a red a black lead... I guess the next step is the test the fuel pressure. Can anyone help me understand how to relieve the fuel pressure so I can add a fuel pressure gage? Thank you