By mistake put regular gas into fuel tank HELP it only ran about 15 mi before it would just die out we drained all the gas out and put disel in it ran for a few mi then would die out,next day tryed it again turns over but wont fire

This would be pointing to the wrong fuel being filled up.
Drain the fuel tank, flush the system, change the filter and re-fill with correct fuel.

it has dirt or debris in the carburetor. you need to take it off and clean it real good. you will see water or dirt specs in the bowl. also before you put it back on. drain and clean the inside of the fuel tank and fuel lines. it will run like new after that.

drain tank put new fuel in it check fuel pressure maybe pump?

Sounds like you have some bad fuel. I would drain the tank and put some fresh fuel in it.

drain gas tank, fuel lines. replace fuel filter. refill gas tank with diesel. bleed fuel lines and fill fuel filter with clean diesel.

Pull the carburetor and clean it for staters.Be sure to change oil any little bit of moisture in the crankcase will let it smoke white by seeping by the valves and piston rings.Also put a little small amount of dry gas in the gas tank to rid all of the water that may have been left in the tank. I some of this will help you.

check all of the vaccum lines and check the timing and see if they have any thing at the auto store for diesel to put in the tank you may have also got a bad tank of diesel fuel. i also had something like this once happen to me and the tank i got it was not diesel someone had put unleaded in that tank by mistake

drain the tank change the fuel filter motor will be fine
it'll run funky until the e85 is flushed out

Follow fuel lines from tank forward, and you'll probably find it along the frame rail.

Check the glow plug timer relay. This is what determines the length of time your glow plugs stay on. If it is cycling off too soon, you will have this problem.,