97 Yamaha VMAX 600

[muddpuppy]

getting ready for the season to come. For the last 2 seasons I have been trying to figure out why the sled is getting so cold blooded. It used to be 2-3 pulls done when it gets cold. Now I could pull all day and nothin unless I use some good ole either.

I have had the carb rebiult and the fule filter replaced. all the fule lines look good. What else could be wrong?

Thanks in advance for the help!

[NAMASafetyDirector]

Could be a small crack or hole worn through the impulse line from the crankcase to the fuel pump causing the fuel pump to work incorrectly making it hard to start.

[muddpuppy]

Thank you for your input, I am wondering if this Impulse line is a fuel or a vacuum line? I was thinking of replacing all the fuel lines and cleaning connectors thinking air may be getting in the lines. But once the sled is started all is good. I would think if there is a fuel or vacuum issue I would get backfires and irregular throttle?

[NAMASafetyDirector]

The impulse line is the hose that goes from the crankcase (usually on back,carb side) to the fuel pump. If the impulse line is cracked or has a small hole in it, the sled will be extremly difficult to start. It may still run after you get it started but if it's cracked the fuel pump won't operate properly making it hard to start.

[Deep_Sinker]

Visit totallyamaha.net. You will find a ton of information on their tech pages as well as asking some of the most passionate yamaha riders.

[icecold]

When is the last time u had the carbs cleaned, usually the pilot jets will become plugged or the choke circut will be restricted with old gas varnish , this is a common problem with todays poor gas, cleaned hundreds of carbs over the past 23 years as a sled mechanic, also check your compression, should be 130-150 if in good shape.

[muddpuppy]

Deep thanks for the link I will check that out. Ice I just had the carbs cleaned and the fuelfilter replaced last season. when it is warm out like 15 and up I have no problem starting just when it gets cold below 15'f