Thanks Phil and Frank for your replies. To answer some questions:

I think the tanks are rated for 300-350 PSI if I recall correctly.

I am currently using 2" hoses with cam-lock fittings. The hoses are 15' long and I use the shortest hose length I can. Most of the time I use two hoses so figure 30'. The vacuum pump uses a 1" hose with 1 1/4" valves and fittings. We have the tanks rigged up with a 2" valve on the top and the bottom of the tank. I use the bottom valve to unload the oil, either by putting air pressure in the tank or using the now defunct pump to pump oil into the heater tanks. I use the top valve to receive oil from the farm. The 'stinger' I stick down in the tanks or barrels just fits inside a 2" bung. My problem with using the pump is that as soon as the pump sees air, it quits pumping and the oil quits moving. This leaves the suction line mostly full of oil and the pressure side completely full of oil. This is a mess at best.

The vacuum works great because it purges ALL the oil from the lines and it is self priming. With the pump I spent a LOT of time getting the pump to prime. I like the 40 cfm that this vacuum pump moves because the rush of air through the lines insures that no oil remains in them. I would like to maintain a continous vacuum in the nurse tank so that when the tank/barrel empties there will be no chance of oil staying in the lines waiting to spill out when I switch barrels, tanks, ect.

We usually begin running the heaters in October and it typically takes from October to December to burn the oil we accumulate over the summer in the shop. Also, during the summer, everyone is too busy doing billable work to gather oil, which is not billable (unless we can convince customers to pay us $64/hr to gather their oil). If it is really cold the water in the barrels is mostly frozen so the water stays on the farm--we can't seem to burn water very well.

If someone has an idea of how to separate the oil from the water I would be interested.

Remember 9-11-01--God Bless the USA
JUSTICE, not REVENGE, will prevail

1951 Chevy 1/2-ton Pickup truck