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400 scrambler hard start

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Old 03-07-2012, 03:54 PM
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Default 400 scrambler hard start

It likes to wet the plug easily. Just barely idle and if i time it right can go otherwise she floods and big backfire when trying to start again. Once running she runs great! I have added stp gas booster to no help. I have tried 3 new plugs and usually starts decent first time but after that no. Any ideas?
 
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Old 03-07-2012, 04:03 PM
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Old 03-07-2012, 04:19 PM
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Have you gone through the carb,replaced the needle and seat,plus cleaned the jets?Plus have you done a compression check?
Plus sounds like it's revving high,slipping?(could be the snow) have you checked the belt? Any exhaust leaks? OPT
 
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Old 03-07-2012, 04:53 PM
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Was raining today I'll pull carb tomorrow and check reeds while Im there.. Wasn't belt slip was tire spin never once felt give. Just likes to not run as well under half but hard starting and gumming up really the problem.
 
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Old 03-07-2012, 04:55 PM
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I stuck my finger in the hole and it got blown out and sucked back in on one stroke. Forgot about pull back scared me a bit lol.
 
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Old 03-13-2012, 08:37 PM
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Check the timing! I had that happen to me, hard to start- wet plug - when got running would backfire and blow exhaust off the machine. the keyway on the flywheel stripped and the timing was way off. I would look here first! let me know if this helps.....
 
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Old 03-14-2012, 07:31 AM
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I will check that thanks!
Checked water pump and fins looked all good but the bearing on end of crank was half gone! Do i need a whole crank bearing kit or can i just get the one?
Also did a compression test and it was 90 but didn't hold throttle wide open so is it okay?
 
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Old 03-14-2012, 11:31 AM
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You can look at Pure Polaris Parts Catalog OR to get prices look at Cycle Parts Warehouse for the engine breakdown of your model! You can either order individual bearings or also try to match em up at auto stores or if you have a bearing supply house nearby,even better! A four stroke gets it's most accurate compression reading by holding the throttle wide open,but not that critical on a two stroke.Try again though with the throttle cracked open and if it's still 90 psi then awfully low!! OPT
 
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Old 03-14-2012, 02:11 PM
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I was just wondering with a bearing bad if it should get a full crank/bearing kit? Still have to figure out how to get the race off she is on there! Thanks for the help guys but Im leaning toward a tear down and rebuild..
 
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Old 03-14-2012, 03:23 PM
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If you're not sure,then its best either to get a manual or tear it down! Don't just try to partially repair something only to have something else bad along with it. Manual will help you decide. OPT
 

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