I picked up a really clean kept in a garage since new, I think 1993 V Max 4 750 , it has sat for a long time somehow oil backed up into the fuel lines, I pulled the carbs everything is Factory perfect, I have not run across this before, it was moved from Wi to Il recently, the former owner said it has not been run for 10 years except on starting fluid sprayed into the boost bottles
NorthofSixty
Member
A friend of mine had the same problem on his 700 triple. On his there is a small check valve in the oil feed line to the fuel pump. I found a thread that described the problem and fix. The check ball in the valve prevents fuel from back flowing into the oil reservoir but also is lightly spring loaded to prevent oil bleeding through the fuel pump and filling the float bowls during storage. Cleaning or replacing the check valve is supposed to fix the problem on the sleds that have a check valve. I had the same problem on my 95 VMax 600 and it turned out to be an oil pump failure and was fixed by replacing it with an upgraded pump from a 98 VMax. Hopefully this helps.