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Discussion Starter #1
Hey gang. New user here.


I'm having a new problem with my 2002 Grizzly 660 where it will start and run great cold, then when it is warmed up and idling, it will sputter and die. Then it will be very difficult to restart. I have read about the vapor lock/fuel boiling issue now and did a bunch of searches but haven't found any real definitive solutions. I have also heard about the dealer 'heat kit' and I think my quad has that installed. When I bought it from the original owner he said something about that. The side panels are vented. I rebuilt the carb and it is still doing it, so that wasn't it.


I have read also about people buying electric fuel pumps and that sometimes working. Other people say to clean out the radiator - which I will do.


If it is vapor lock, which it seems like it is - is there any heat shielding I can do around or on the carb or fuel line? I have some header wrap that I can wrap stuff with. I also have some spark plug boots/wrap that I thought could maybe slip right over the fuel line. Thoughts?


thanks
 

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When was your valve clearances last checked, if they ever were?
If you have never done them, I would start there as they should be checked and adjusted, if required. If they are tight, it will give you running issues.
 
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If it is vapor lock issue opening the fuel cap should release the pressure and let it run better you could try that next time it does it.
 
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Discussion Starter #5
I did adjust the valves. The intakes were tight so I set those correctly. Exhausts were ok.


And I tried removing the gas cap - no difference. There was no pressure build up.


I am wrapping everything with header tape, and adding some heat resistant tape/material to the under side of the gas tank and where ever it looks like it might help. I will also see if I can find any octane booster, or just replace the fuel with premium. Over the next couple days. I'll post the results.


thanks
 

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I have a 2016 grizz, seems to be doing the same thing, try and ride it no power, backfires you have to finger the throttle to keep it running. I took it to dealer they said i had sand in my fuel system, ran good for a little while then done it again, cleaned out again then it done the same stuff again. Talked to a fella he said change fuel pump so i did, didnt help. so i rode it hard after putting the fuel pump in to make it do it, and then i pulled it in the shop and i unplugged the air temp sensor held the break and floored it and it immediately spun the tires, plugged the sensor back up and done the exact same thing and it went to spitting and sputtering until i fingered the throttle. I done the fuel sensor and TPS the same way no change with them, so i ordered an air temp and we will see if that fixes it
 

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Any luck robgriff? I've got the same thing on my 2012 Griz 700
 
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