Need help with starting problems.

[A K MtnViper]

My sled starts great when cold with choke on. Runs super all day long. But, when I shut it off for 1 minute or 10, it will not start without full throttle and even then it acts like it is loaded up for several seconds. Ran perfect the first couple of rides this year but now I'm ethier getting worn out pulling at least 20 times or letting it run all day. Anyone have a idea what to look for.
Please help.

 

[snowdad4]

i always hold the throttle about 1/4 when pulling the rope. we call it the yamastart technic. have even passed this down to my kids. perhaps by giving full throttle your are causing a flooding of sorts. try the yamastart, it will become second nature.

 

[A K MtnViper]

i always hold the throttle about 1/4 when pulling the rope. we call it the yamastart technic. have even passed this down to my kids. perhaps by giving full throttle your are causing a flooding of sorts. try the yamastart, it will become second nature.

That is the way I always started it before. Now that does not work at all. I could pull 40 times at 1/8 to 1/4 throttle with no chance of it starting. I have had Yamahas since 94 and never seen this one before.

 

[tedgoesfast]

possible needles leaking by.My 700 did this replace needles and sets still have to give it a bit of throttle to start but not as bad

 

[maxdlx]

Are your carb heaters on

 

[snomoguy]

AK
Maybe float levels have changed (richened) if you haven't checked them lately. I usally check mine every fall and set them slightly to the lean side. During the season they will gradually get richer, due to trailering, jumping, or just normal riding on rough trails. You'll be surprised how that little tab can get bent.

 

[A K MtnViper]

possible needles leaking by.My 700 did this replace needles and sets still have to give it a bit of throttle to start but not as bad

I'll try that and Check the Float levels also.

Thanks for the suggestions, both of you.

 

[alswagg]

pressure test the needle valves, they should hold 3-5lb. pressure. When carb is uside down, pressure test through fuel inlet, hold float tab down with slight amount of pressure. Watch the gauge, and should remain constant. If pressure falls, needle valves are bad. You can verify where the leak is by spraying a small amount of WD 40 on the suspected area, bubbles will show where air is passing by. Good Luck Al

 

[gild]

Choke

Make sure your choke plungers are closing and not hung up. It will start cold but not hot . been there done that, electric start all the way

 

[A K MtnViper]

Make sure your choke plungers are closing and not hung up. It will start cold but not hot . been there done that, electric start all the way

Would the sled run great with the choke plungers stuck?

 

[gild]

idle

If it idled too long it would load up and got worse the higher you got but down low it ran fine at WO and trail speed

 

[snomoguy]

AK
What did you find out?????

 

[A K MtnViper]

AK
What did you find out?????

Have not even looked at it yet. Gone enough this year to be burned out a little. Going to do one more big trip March 15th ish in Southern Colorado. Will fix before than and post answer

 

[A K MtnViper]

Found the problem and fixed it. I'm not happy to report on the problem, but here goes. I forgot to replace my plugs, like I do every year. Put in new plugs, now runs and starts perfect. , I hope this is not the start of Oldtimers.

 

[Powder Trax]

Its called "SOMETIMERS Disease"

Sometimes you remember, sometimes you dont.

Good thing you remembered something to check.

Just poking some fun at you.

 

[A K MtnViper]

Its called "SOMETIMERS Disease"

Sometimes you remember, sometimes you don't.

Good thing you remembered something to check.

Just poking some fun at you.

I had that coming .
But on the brighter side, rode Friday and Saturday and never saw a sled or a track 10 miles out of the parking lot. What makes that remarkable is that the manufacturers were doing their tests on the new sleds on Saturday. Leaving for Steamboat area Thursday, snow is great according to my friends up that way.