I've got a 1990 F150 with some really old gas in the rear tank I was wondering if there is a plug to drain it or not. Thanks
Draining a 1990 F150 gas tank
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I am not certain about an F150, but a friend of mine has an '88 F250, and removing the bed was the most straightforward way to get to the tank.
If I were you, I would clear out as much as possible with a siphon, dump in a couple of gallons, and do it again. Good luck.
If I were you, I would clear out as much as possible with a siphon, dump in a couple of gallons, and do it again. Good luck.
Pop a fuel line off after filter....turn key on to drain tank...refill with clean fuel..turn key on to flush out fuel lines...put new filter on...connect everything back...done...let truck do the work.
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Originally Posted By: DSparks
Pop a fuel line off after filter....turn key on to drain tank...refill with clean fuel..turn key on to flush out fuel lines...put new filter on...connect everything back...done...let truck do the work.
The fuel pump will probably only go 10 seconds unless the relay sees a signal from the oil pressure sender or similar. They have some kind of safety feature you would need to override to get the pump to go continuously.
Pop a fuel line off after filter....turn key on to drain tank...refill with clean fuel..turn key on to flush out fuel lines...put new filter on...connect everything back...done...let truck do the work.
The fuel pump will probably only go 10 seconds unless the relay sees a signal from the oil pressure sender or similar. They have some kind of safety feature you would need to override to get the pump to go continuously.
Turn key off...turn key back on...sure beats pulling tank or bed imho...
Under the hood, fuel relay is marked, wiring/contact diagram should be cast into the relay body. Short the secondary to hotwire the pump. Simple as it gets.
Originally Posted By: punisher
Under the hood, fuel relay is marked, wiring/contact diagram should be cast into the relay body. Short the secondary to hotwire the pump. Simple as it gets.
Yeah, no point getting carpal-tunnel turning the ignition switch back and forth
Under the hood, fuel relay is marked, wiring/contact diagram should be cast into the relay body. Short the secondary to hotwire the pump. Simple as it gets.
Yeah, no point getting carpal-tunnel turning the ignition switch back and forth
No drain plug. You will have to jump the relay to make it pump with the engine off. Turning the key on and off will take weeks @ 1/2 oz every time you turn the Key on.
I'll 2nd pulling the bed. Takes about 1/2 hr and is much better than dropping the tank.
I'll 2nd pulling the bed. Takes about 1/2 hr and is much better than dropping the tank.
How old is the gas?
Originally Posted By: Donald
Originally Posted By: DSparks
Pop a fuel line off after filter....turn key on to drain tank...refill with clean fuel..turn key on to flush out fuel lines...put new filter on...connect everything back...done...let truck do the work.
The fuel pump will probably only go 10 seconds unless the relay sees a signal from the oil pressure sender or similar. They have some kind of safety feature you would need to override to get the pump to go continuously.
Won't run more than two seconds unless ECM is receiving a ign pulse that verifies engine is running...
You all are doing it the hard way...
On test connector, ground pin marked fuel pump(grounds control side of relay coil), pump will continually run with ign on..
Originally Posted By: DSparks
Pop a fuel line off after filter....turn key on to drain tank...refill with clean fuel..turn key on to flush out fuel lines...put new filter on...connect everything back...done...let truck do the work.
The fuel pump will probably only go 10 seconds unless the relay sees a signal from the oil pressure sender or similar. They have some kind of safety feature you would need to override to get the pump to go continuously.
Won't run more than two seconds unless ECM is receiving a ign pulse that verifies engine is running...
You all are doing it the hard way...
On test connector, ground pin marked fuel pump(grounds control side of relay coil), pump will continually run with ign on..
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