ringo234

What is a Sump? Is it to prevent gas from sloshing around and keep the pump from momentarily running dry? If so how do you do this Mod? Is it very hard?

Thanks

87CIZ

iTrader: (8)

basically its just like an oil pan it has a spot where oil stays to keep the pickup from going dry so you have the right idea as to what it is. I dont know if you've noticed but when you go around a turn pulling some lateral g's all the gas goes to one side and you might let the fuel pump go dry for a second or 2. well the sump keeps it wet. It's basically drilling a couple good size holes in your gas tank having the sump welded on and getting an external fuel pump to supply the fuel.

BMmonteSS

Keep in mind you HAVE to do this to a brand new tank, there is just no safe way to weld on a tank once it's had gasoline in it. I know several people who have been serisously disfigured or killed from welding on gas tanks, or even welding near a gas tank.

If you have to ask what sumping is you don't need it. The only time this becomes an issue is under extremely high lateral G's with less than a 1/4 tank. GM designed a swinging pickup for the 1LE cars, you migh want to try to mimic this design and stay away from fabbing on gas tanks.

ringo234

I just wanted to know what a sump was. That doesn't mean I didn't notice the pump running dry when getting low on fuel. In fact since my fuel gauge doesn’t work all that well that's one of the ways I no to buy gas, that and keeping track of my miles.

Is it possible to swap in a 4th gen tank?
Would that fix both my problems?

Thanks

xpndbl3

iTrader: (5)

bmmonteSS has no idea what he's talking about. Pull out your tank and take it to ANY radiator repair shop around the country, they will then drain it and fill it with water, then fill it with an inert gas to weld a sump on the bottom. Almost every serious drag racer has it done to his tank or runs a fuel cell. Under hard acceleration it keeps fuel available for the pump. Typically it uses -8 or -10 lines out of it. If safety concerns are addressed welding an old gas tank should not cause serious injury.

Unless you're running such a high demand fuel system it's not needed as a walrbo 255lph can fuel some serious HP.

BMmonteSS

Thats funny because every radiator shop around here won't touch a gas tank. There is just too much to go wrong with relying on an inert gas to keep the gasoline vapors from igniting. I work in the natural gas industry, I work around blowing gas on a daily basis. The same welders that will weld on a 20" gas line with 100 psi of pressure on it won't even think about welding on gas tanks no matter what their filled with.

BigDreams92

iTrader: (1)

Sumping of used tanks happens everyday. Radiator shops tend to shy away from our tanks b/c I guess some of the newer ones are lined and are a PITA to weld. Atleast that's why the radiator shop stayed away from mine.

83 Crossfire TA

iTrader: (2)

Hot taps in gas lines are significantly different then welding on a gas tank in that you have a presureized, non flamable gas in the gas line (the natural gas has no O2 in it and will not burn without adding O2 to it). Both can be done safely, but in both cases you absolutely HAVE to keep any O2 away from the weld area or you’re in deep kaka…