I'm a bit confused about how to release the fuel pressure so that I can install a new fuel pump in my 1994 850 Turbo. Trouble is, I just filled the tank with gas before my old fuel pump died so I can't drain the tank (don't have the equipment to drain the tank either).

So far I think the simplest method I've read for releasing the fuel pressure is to remove the cap from the Schrader valve on the fuel rail. But I'm a little confused about this as well. Will gas start gushing out of the valve? Or do I have to unscrew the cap and then push in a pin? Or do you just remove the cap and 'pssssst!' the excess pressure is released without the entire tank of gas pouring out?

Thanks for you help.

 

If your fuel pump went out you likely won't have a lot of pressure in the fuel system.

There is a pin to push in on the Schrader valve, and no the whole tank won't come rushing out. It'll likely be a little disappointing how much fuel actually comes out.

Don't forget to change your fuel filter after changing your pump.

 

Best way to relieve fuel pressure is to pull the fuel pump fuse or disconnect the electrical connections to the pump, then start the engine. When it dies, or if it never started to begin with, crank the engine for 15- 20 seconds. This will purge the lines of pressure and let you change the pump.
and +1,000 on changing the filter afterward!

 

Thanks guys. Turns out there was no fuel pressure to speak of after all. Took the cap off the Schrader valve and depressed the pin. No gas came out. Was able to replace the fuel pump with no gas spilling out.