Here is a little background on this ATV:
I bought it just before christmas 2012 for $300. No brakes, no electrical, no starter, no AWD. It actually ran pretty good though. Maintenance was a word the previous owner had never heard in his lifetime.
So far I have replaced the battery, all 3 brake calipers, starter, bored out the engine .020 with new piston and rings, replaced the stator, coil, cdi, start switch and a few other electrical parts. The bike runs very well now.
The oil tank looks like it hasn’t been used in decades. It is bone dry and the PO claimed he just pre-mixed his oil/gas. I have no idea if the oil pump works or not.
Now for the question: should I go through the trouble of checking it, or just run pre-mixed? If I run pre-mixed (I would rather not) what do I have to do to make sure everything is unhooked/plugged properly?
I have done extensive searches here and elsewhere and it just gets more confusing. I don’t want to remove the oil pump, or block it. Some posts say to do so, others say just block the line with a 6mm bolt and washer. Others give lengthy explanations of what to do to convert.
What exactly do I do? How do I check the oil pump to make sure it works? Or do I just block it and pre-mix?
What is the consensus, if there is one?

Thanks for you time and experience.
bob

 

The 6mm bolt and washer is for the 400 engine oil line block off.Loosen the 10 mm bleed screw on the pump first and remove any trapped air. If you're not sure on the pump,just pull the injector line from the cylinder base fitting that comes from the pump. (put a rubber plug over the cylinder fitting)You can either have an auxiliary tank mixed 50-1 hooked to the carb or just mix 50-1 in the tank,won't hurt, will only smoke a bit more until you refill. At an idle, hold the pump arm all the way up and see if the injector line dribbles oil. You can tell real quick if the pump is working or not. Pumps are usually dependable on the old 250 engines. It's the 400 pumps that freeze up or get water past the cover that have problems the most.

 

Thanks for the info OPT. I haven’t forgotten about this, I’ve just been slammed at work. I’m still having a little difficulty finding everything as it’s supposed to be.