53 replies to this topic

[Yellow Jacket]

 Rear PDC, Fuel Pump Relay.pdf   227.93KB   20 downloads

 

Per the service manual, you want your tank to be less than 5/8 full when you open it, but the lower the better. Instead of driving around to burn gas, you might find it easier to use the fuel pump to empty the tank. 

 

All you need is some tubing that you can attach to a fuel crossover. For instance, in the 6.4L engine, the stock crossover is 3/8" fuel line. Get some cheap 3/8" vinyl tubing and a "T" barb fitting. You can use this to tap into the crossover, emptying it into a gas can. If you've upgraded the fuel rails, you might might have some ports you can tap into, or crossovers that disconnect. If you have a lift, you could also just disconnect the fuel line from the rails at the quick disconnect and empty it straight down into a bucket.

 

Before you start disconnecting anything, though, you need to relieve the pressure in the fuel system. The more recently you've driven the vehicle, the more residual pressure you'll have.

 

1. Pull the fuel relay. It's located in the Power Distribution Center in the trunk. I've attached a PDF so you can find it easily.

 

2. Start the engine, or at least crank it a few times.

 

3. Now tap into your fuel system, and set it up so it drains into some sort of gas container.

 

4. Jump terminals 30 and 87 of the fuel pump relay. When you're looking into the trunk, with the fuel pump relay removed, those are the upper left and lower right terminals (or using the car's orientation, driver side front, and passenger side rear). You'll hear the fuel pump activate, and the fuel will start emptying into the can.

 

It takes just a few minutes to empty an entire tank this way. I always like to keep my tank nearly full, so it's hard for me to time the start of a project with an empty tank. Knowing how to empty your tank like this can save a lot of time, or at least allow you to start your project whenever you want to. 

 

 

[Roomraider]

Good stuff here Howie!

[J-Z]

Throw a match in it?

[toofart]

Shit for a minute I thought you were asking again.

[Yellow Jacket]

Denis. I did forget some of the details after I did it the first time, so I posted this as kind of a reminder to myself, if I ever have to do it again. Luckily I still had the tubing that I rigged from before.

[toofart]

Yep, good deal.

[Corrupted]

Good to know. I'll try this at the track once I get my car back.

[Yellow Jacket]

Oh yeah, it's nice not to have to carefully calculate your gas usage prior to switching to race fuel. And with your tank as empty as possible, you get the most out of the good stuff.

[novawagonmaster]

Good stuff Howie.

 

I took about 8' of plastic fuel line a put an end on it that mates to the factor feed line quick-disconnect fitting at the fuel rail. Just drop the other end into a gas can and clamp it in place so it cannot come out as the fuel begins to flow.

[Yellow Jacket]

John, where did you get the fitting that attaches to that factory fuel line quick-disconnect? I've been looking around for one that's a T because I need to tap into the pressurized fuel and don't have ports in my rails. I can T into the center crossover, but that seems less elegant to me.

 

Clamping it to the gas can is a great idea. Especially if you have kids or dogs walking around. I just stood next to it and guarded it until it was done.

[JS1977]

will be using this when I switch mine out this week!

[novawagonmaster]

Howie, I made it at work.

[Yellow Jacket]

 

The only useful thing I can get from work for my car is rags. Oh, and maybe some N2O, but that requires a little more work and sneakiness.

[Speedy]

Nova, you wanna make a few for us?  I could use one as well.

 

Howie, where the pics and vids?

[Yellow Jacket]

. That's your territory, dude. I can't compete with Speedy's Garage.

[novawagonmaster]

I'll see what I can do.

[Yellow Jacket]

That would be awesome, John! I need mine with a T to a 1/16" NPT hole, or a 4AN male. But I'm sure I can get an adapter fitting for whatever you can make.

[Speedy]

Sweet Jon.  Lemme know what you need cabbage wise for your time, or I can pay you in beer at CF5

[novawagonmaster]

That would be awesome, John! I need mine with a T to a 1/16" NPT hole, or a 4AN male. But I'm sure I can get an adapter fitting for whatever you can make.

 

I don't have that stuff on hand. I have what I need to hook up to the factory feed line quick disconnect at the fuel rail.

Sweet Jon.  Lemme know what you need cabbage wise for your time, or I can pay you in beer at CF5

I don't drink beer, but something along those lines will be fine.

[Yellow Jacket]

Oh, so it's not a T but an adapter for your tubing to drain the tank?