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2000 Kodiak 400 installed known-good carb, but still won't start

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  #11  
Old 06-06-2016, 08:03 PM
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Originally Posted by DirtDevil101
Ah yes...was thinking 2-stroke...sorry! Well...you're definitely getting fuel, you say you have spark...I'm down to compression and timing...I wouldn't think the valves out a bit would keep it from starting...unless one is bent and stuck open/close.


How quickly did the engine flood with fuel? The leak-down past those rings should be pretty slow...
It's hard to say how quick. I just tried to start it and it acted like it was locked up. Later, I got the idea to check the airbox, and it was filled with gas. My buddy ordered an adapter for his compression checker to fit in the quad, so I should be able to test that soon. If the valves are tight, would compression also be affected?
 
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  #12  
Old 06-07-2016, 11:32 AM
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Short answer is yes...improper valve seating will impact compression. Does your head have valve windows to check them? Either way if you get a lower than spec compression reading you're probably going to need to start tearing it apart...not a fan of thumpers for this very reason...too many moving parts IMHO...
 
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  #13  
Old 06-07-2016, 09:05 PM
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Originally Posted by DirtDevil101
Short answer is yes...improper valve seating will impact compression. Does your head have valve windows to check them? Either way if you get a lower than spec compression reading you're probably going to need to start tearing it apart...not a fan of thumpers for this very reason...too many moving parts IMHO...
No, I have to take the cover off. My biggest issue is ensuring that I'm at top dead center on the compression stroke.
 
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  #14  
Old 06-07-2016, 11:47 PM
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Originally Posted by donw
No, I have to take the cover off. My biggest issue is ensuring that I'm at top dead center on the compression stroke.
If the airbox is full of fuel, the you built the carb incorrectly and it's flooding. Re-visit the carb, get it right, change the oil again and install a new spark plug.
 
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Old 06-08-2016, 12:29 AM
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Originally Posted by Fasteratv
If the airbox is full of fuel, the you built the carb incorrectly and it's flooding. Re-visit the carb, get it right, change the oil again and install a new spark plug.
Thanks, but I think you missed the post where I switched carbs with a known good one, and it still will not start.
 
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  #16  
Old 06-08-2016, 09:40 AM
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Originally Posted by donw
Thanks, but I think you missed the post where I switched carbs with a known good one, and it still will not start.
If you cleaned the airbox prior to installing the second carb ( I assume you did...LOL ), and the airbox is full of fuel again, then the float is hanging/stuck or you have the fuel line connected to a carb vent instead of the fuel inlet.
 
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Old 06-08-2016, 10:42 AM
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Originally Posted by Fasteratv
If you cleaned the airbox prior to installing the second carb ( I assume you did...LOL ), and the airbox is full of fuel again, then the float is hanging/stuck or you have the fuel line connected to a carb vent instead of the fuel inlet.
The airbox is not full of fuel again.
 
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Old 06-08-2016, 10:49 AM
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Originally Posted by donw
The airbox is not full of fuel again.
But the engine was...and it hydro locked with the known good carb? From excessive fuel? Just trying to follow you here.
 
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Old 06-08-2016, 11:36 AM
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Originally Posted by donw
No, I have to take the cover off. My biggest issue is ensuring that I'm at top dead center on the compression stroke.

Do you have a manual? I'd think there would be timing marks somewhere to assist in TDC/valve lash adj. Every machine is different and I'm no expert on the thumpers...
 
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  #20  
Old 06-08-2016, 11:43 AM
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Check this video...it'll get you started...



 
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