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I think that is definitely something to look into though I only have 60 hrs on the machine, I literally only use it around my yard. Would that be something that would all of a sudden cause the engine not to start?
If you look in the owners manual, look for the recommended time/hours to check the valve lash.
Then a lot of start/stopping usage without blowing the cobs out and building engine heat will slightly foul the plug. These are low compression, low output engines so small changes cause problems.
On my bike at 60 hours I would have been around 600 miles, with several heat cycles on the engine and this causes any valve stem stretching.
Based upon the thread title, something has changed and I would check the valves and install a new plug. Then once you get this figured out blow the cobs out every week or two on a good long day ride.
 

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Sorry to start this thread back up, did you ever figure out the issue? My 16 just died on me last night and I cannot get it fired back up. Getting fuel, has spark, I'm lost.
How do you know it is getting fuel? Can you hear the pump? Did you remove the fuel line to check for fuel?
Do you have a service manual?

Yep, replaced the spark plug last night, had one already for my next oil change. Hopefully the battery will help. In the past when spraying chemicals on the Grizz, the motor has died, I'm guessing from the power draw of the sprayer pump, but fired back up.
Check and clean all of the battery connections from the battery to the starter and to ground.
The fuel injector need 7 volts to open. Low voltage will stall the engine.
A bad battery, cables, and/or dirty lose connections maybe the problem.
A bad stator not charging the battery properly is another possibility. Do the easy stuff first.

Valves can go 4-5000 mile before needing adjustment. The valves tend to tight up overtime. This causes the intakes to hang open a little, leading to hard or no starting but not stalling.
 

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Hey all, just wanted to come back and tell you what happened. I took the fuel pump out and there was all sorts of slimy gunk in the tank, the strainer had a jelly-like film all over it. I'm not sure if my youngest kid put something in the gas tank (he likes to put gas in the mowers and in his little quad, and maybe once he dumped used oil in my lawnmower gas tank), but it was cloudy and there was definitely some chemical separation going on. I used my air compressor to blow the fuel pump strainer out and reinstalled it. I blew the fuel line out and it fired up. It ran okay for a while but is still cutting out on me. I have ordered a new strainer but I am worried maybe the injector or fuel pump may have some of the gunk clogged in them. I may consider ordering a new fuel pump and injector just to cancel out all doubts. I will post back when I install the new strainer and let you know if that fixes it.
 

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2017 Kodiak 700 ESP SE
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Even If that works add a good injector cleaner to the gas also.
 

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And if you can take'er for a good long day ride and run some fresh gas through'er to clean out the system. You can bet there is crap in the pump and the injector that needs pushed out with a few gallons of new gas.
I use injector cleaner in mine every now and then, and try to run most of out to not let is stay in the tank for weeks at a time. Over night is OK, but some cleaners are hard on the rubber line so once I am done riding with a gallon or so left in the tank I top of the tank to dilute what remains of the cleaner. If you're unsure how long you can ride, do a couple gallons and carry extra gas, untreated, to add during the ride.
 

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And if you can take'er for a good long day ride and run some fresh gas through'er to clean out the system. You can bet there is crap in the pump and the injector that needs pushed out with a few gallons of new gas.
I use injector cleaner in mine every now and then, and try to run most of out to not let is stay in the tank for weeks at a time. Over night is OK, but some cleaners are hard on the rubber line so once I am done riding with a gallon or so left in the tank I top of the tank to dilute what remains of the cleaner. If you're unsure how long you can ride, do a couple gallons and carry extra gas, untreated, to add during the ride.
I went ahead and ordered a new pump and injector, I'll probably clean the tank one more time and blow the fuel supply line out again real good... I am just happy not to have to buy a new ECM. I will also look into a locking gas cap to ensure nothing makes it's way back into the tank. Once I am done with that I'll take it on a long ride along the railroad tracks and get the system all blown out. I took advantage of having it all apart and flushed the coolant and replaced it with engine ice, it always treated my YFZ450 well.
 
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