Fuel pump shuts off when hot?

SO, my VKPro ('11, 1000miles ) will stutter and then quit when running full out when warm. Or when I'm pulling a load. I work at 12,000 taking care of ski huts in Colorado. I pop the hood, and check to see if fuel is available by pulling the fuel line off the fuel pump (?). With fuel available, I can get the beast to run with some fuel tossed in the open carbs. I have struggled with it for an hour or two, but 15 miles out it seems worth it. Then, it seems to run again, just fine. An intermittent problem, seems to happen when operated at full throttle more than at half throttle. Would the fuel pump or distributor just lock up? Or is this a problem related to carberator heating? Seems awkward making it run by squirting fuel in the open carbs and then choking the #$%@ out of it.

This sounds to me like your engine compartment is getting way too hot. There is a rubber flap that covers the carbs to hold in heat in extremely cold temps, on milder days this cover should be flipped to lay on top of the air box so that the carbs are vented. What kinds of temperature are you experiencing this problem in? If excess heat is causing this I would suggest adding extra cooling such as a radiator or heat exchanger.

I have been running with the rubber flap down, no idea that was for a heat management thing. My problem does seem to occur on the warmer days, particularly after the machine has been thoroughly warmed up and then is run full throttle (for example to pull a long, steeper hill). Imagine getting to the crux point of a powder hill, and then having the machine stutter...
What exactly is shutting down? Is this computer driven shutoff for the fuel pump?

you might also want to pinch off the coolant line to the carbs. i used to use a strong wash line pinch pin on my rx when temps got this warm out. seemed to help quite a bit.

fuel pump is vacume operated so i would bet the gas is getting too hot in the carbs as i do not think the vk has gone fuelie yet.

I agree with maim that the fuel is getting too hot in the carbs. In my 05 vector owners manual it said to flip the rubber flap depending on outside air temps. Yes pinching off the coolant lines to carbs would also be effective.

OK, I will give it a try, flip the rubber cover back, and pinch off coolant leads to the carbs. I'll be dragging firewood logs in to the huts soon so I'll let you know if these measures help. Thanks!

my 09 viking has a shutoff for the carb coolant lines. I would think your 2011 has one too?

I'll have to investigate it! I think you may be right, I thought there was a fuel shut-off placed on a line to the carb bodies and just assumed it was a fuel line, not being quite clued in to the heated carbs thing. I'm regretting not following up with my out of area dealer and getting an owners/operators manual....

The '11 VK-pro does have the coolant/heater shutoff. I flipped the rubber heat map back off the carbs, shut off the coolant/heater to the carbs, and went logging. The temps were 30F to 40F, then the snow got too soft to continue hauling logs. I had one little stutter but primarily the machine performed flawlessly. I love it when my main worry is where the next good standing dead tree will be, and not whether or not I'll have to ski home...
Thank you guys for the operating tips! I'll try to post a pic of the logging drag I've been using.