Summit 670 Starting problems

Toy4Fun

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My 1996 Summit 670 has been starting good when its cold but once warmed up its not starting. I rode it for the first time yesterday and it ripped down the trail. I shut it off when we came to a downhill overflow area and after pulling it about 200 times it wouldn't start. It has spark, I put new plugs in it, burned off the fuel in the cylinders with a lighter about 10 times. It would almost start when I held the throttle open like it was flooded but it wouldn't run. I eventually left it and my friend gave me a ride to the trail head. I have to go tow it home today with my polaris and wondering if there are any tips that you guys use to get the 670's started.
 

Toy4Fun

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This is the same machine that I recently went through the whole engine, its fresh so compression isn't the issue. It wasn't running rich and ran good going to where it wouldn't start. I when I shut it off it was slightly down hill so I suspected flooding but can't figure out why it wouldn't start... Oh and the HAC system has been eliminated, it is straight jetted 240-260 mains with powerjets to make up the difference.
 

Modman

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This is the same machine that I recently went through the whole engine, its fresh so compression isn't the issue. It wasn't running rich and ran good going to where it wouldn't start. I when I shut it off it was slightly down hill so I suspected flooding but can't figure out why it wouldn't start... Oh and the HAC system has been eliminated, it is straight jetted 240-260 mains with powerjets to make up the difference.

Your float levels need to be changed. If you park facing downhill and it floods then they are set wrong. The 583's were really bad for this, I think the spec was like 22mm or something but guys were setting them a little higher to cut off flow when pointing downhill. Turn the fuel off if you gotta park facing downhill or if you flip it over, a common mod was to move the fuel shut off to the outside of the pull cord panel so that you could shut it off without lifting the hood (in the event the sled flipped on its lid - lifting the hood is impossible anyway).
 

Toy4Fun

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It started up when I went back today, it ran like it was flooded then cleared out and ran good. I rode it for about an hour and shut it off in the flat parking lot at the truck and it did the same thing. Floats may be the cause or possibly the needle valve and seat?
 

Plattler

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I had a 95 Yammy that ended up with "sinks" instead of floats. Fuel saturated them. I put them in a small jar with gas and they went right to the bottom. After replacing them the sled ran great.
 
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