I was pulling a yard sweeper prepping for fall overseed and the 700 stuttered and died like it was out of fuel. I switched to the rear tank and tried to start it up. It started but would barely run when you pushed the throttle. I could get it to limp along with partial choke long. Did it long enough to get the yard done. Quick research sounded like something in the carb from the tank. Figured I pulled something out of the back tank. Pulled the carb cleaned it and put it back in. Check fuel filter and didn't find anything, but went ahead and replaced it. Still wouldn't run for crap. Purchased new carb and installed and still having same issues. Even with the choke can't go over half throttle. With no choke immediately dies when you gas it. Fuel pump is new, filter is new. Recently wrapped the exhaust pipe to keep from baking my leg and replaced the donut gasket at the header. Spark plugs were replaced about two years ago. This is a small farm ATV; it may get an hour of riding a week on average.Both tanks yield the same result so not a vacuum issue. I've seen a few comments on other threads about checking valve clearance, but I'm finding mixed information that this may have hydraulic lifters and not need checked? Carb boot looks good. I'm on my third one and opted for OEM the generic ones wouldn't hold up. I've seen some other threads about the ignition system. This is a not so common breed of sportsman, so it's hard to find what changes were made for the DoD. Anyone have any ideas?

 

Did you check the fuel flow after replacing the fuel pump? It's not likely a problem but you never know. If that's good I suspect the ignition system but can't recall what years were bad, and don't know if the MV used the same bad one.

 

Check that you're getting fuel from the main tank and the reserve tank in to the fuel valve(#12). Not uncommon for fuel valves themselves to clog up also and need replacement. Also check that the vacuum line from the pump to the carb is ok,not kinked. Pulling vacuum on this line with a mityvac can check if fuel is at least flowing through the pump reaching the carb.If not then again it might be a fuel valve. MV7 came out in 2005 so it has the later Kokusan ignition.I'd keep the oem Mikuni carb. I don't trust these knock off Chinese BST34 carbs. Some are hit and miss.https://www.ebay.com/itm/Shindy-Carb...xZeW6U&vxp=mtr

 

Thanks! I'll double check fuel flow. I thought mine was a 2004 model. I had checked it when PurePolaris used to have their VIN check tool (4XACH68MX4A0Spam wordSpam word Spam wordSpam word Spam wordSpam word Spam wordSpam word Spam wordSpam word Spam wordSpam word Spam wordSpam word Spam wordSpam word *). That showed it as sold to the DoD. I got it from a state police auction.

 

Possible that it could have been made late 2004 but still considered a 2005 model. One year only model production run on the MV7. Also they had two Kokusan stators,one on models build prior to March/2005 and a different part number stator after this date.Tough machine over all and heavily reinforced.And HEAVY...

 

It is a tough machine. Taking it apart to access various areas for maintenance makes for a large pile of nuts and bolts. When it's running well it's a great machine.