I have a 95 425 mag and it runs great but i loaded it up on the pickup with ramps the other day and when i came back later it had dumped all of its oil in the back of the truck.
I then took it home refilled it drove it around on flat ground,it ran good and i shut it off and let it sit over night and it did not drop the oil. The next day I reran it and then drove it slightly up hill to the garage and shut it off and by the next morning it dropped all the oil. Is there a check valve between the crankcase and an oil reservoir where if i go up or down a hill it may be putting to much oil in the crankcase and buidling up too much pressure where it then it kicks out the oil? Any other ideas?

 

First off how much oil was in the atv to begin with and how much did you put back in? The oil tank has a vent at the top of the tank that goes to the air box and also I believe the crank case vent also. If over filled would usually go out the vents into the air box and out the bottom if the drain plug is missing? Check in the air box for any oil first. Plus check that the vent lines aren't kinked.Plus check all the fittings on the tank and oil lines going into the engine. Keep us updated. OPT

 

thanks, i will take a look, i have more time than money

 

Don't we all! OPT