Fuel filter change safety question

[afonseca]

Hi everyone, I'm going to be replacing the fuel filter on my '88 944 and thought I'd ask a question about safety since it's my first time doing this.

Reading up about the procedure I'm thinking of going with the pull the fuel pump fuse and run the car until it kills to depressurize the system method. This seems better instead of clamping on an old fuel line. I'll also open the gas cap to release any pressure before starting. The thought is this should minimize any fuel showers while getting the filter loose.

The question I have is if it's safe to do this in my garage which houses the water heater with a gas pilot light on. The heater has a warning about danger from gas fumes nearby. The garage is a two car garage in an L shape with the heater tucked in on the short side of the L and the car rear would be about 20 feet from the end so I won't be working "near" it where any fuel spill/spray would be an issue.

Should I be concerned with any fumes making their way over to the flame and posing a fire hazard if I'm working with the garage door closed? The thought is depressurizing the system would prevent that but I'd rather be safe than roasted.

Thanks!

[Gawernator]

It would make more sense to me to not do that in an enclosed space. At least have the doors/windows open

[afonseca]

Thanks, that makes sense. Thinking about it maybe I'll go a step further and turn off the water heater while I do this and then let the garage vent a bit before I fire it back up.

[flash75]

My 86 944 wouldn't run with the fuel pump fuse removed.

Clifton

[afonseca]

Originally Posted by flash75

My 86 944 wouldn't run with the fuel pump fuse removed.

Oh yea? Just wouldn't start when you pulled the fuse? Do you think it's because it didn't have enough fuel to start or because the fuse wasn't in? If the former, then that probably accomplished depressurizing the system.

[flash75]

Originally Posted by afonseca

Oh yea? Just wouldn't start when you pulled the fuse? Do you think it's because it didn't have enough fuel to start or because the fuse wasn't in? If the former, then that probably accomplished depressurizing the system.

I think It was because the fuse was out. After not getting it to start I removed the fuel
rail and it appeared to be full of fuel.

[FransB85]

just clamp the fuel line, if it can't handle that it should probably be replaced anyway. take a pair of vice grips and line them with something softer like strips of wood (I sometimes use chop sticks to put the vice grips on) and clamp them off, making sure it's not too tight. you'll want to clamp it shut, not squeeze it too much. there should be no problem and as I said, if they crack it's better they do when you are there anyway because it means they're bad.
good luck!

[89-944NA]

If nothing more, I'd put the rear of the car OUTSIDE, fuel vapors travel, and the slightest breeze can carry those vapors right over to the pilot light....best case would be to either do the job outside or temporarily turn off the water heater pilot light

[afonseca]

Thanks for the tips everyone. I'll definitely play it safe and just turn off the water heater while I do this as the weather's been pretty rainy here. I had my doubts which is why I asked and just wasn't sure about the fuel vapors.

I got the idea to depressurize the system from the fuel pump replacement instructions on Clark's Garage so thought this would save any strain on the fuel line.
Fuel Pump Information and Replacement

Reading back over the instructions again it does mention the car may not start, but if it does to let it run until it does so I think this should work. I don't mind replacing the fuel line if needed but would rather not push it if I can help it.

[skyhawk5421]

My early car ran for at least 5 minutes with the fuel pump disconnected, and it still made a mess. If you've got the same style low pressure pre-pump hose that the early cars have I recommend clamping that with a pair of vise-grips, mine is original and still very flexible.

[afonseca]

Wow, 5 minutes? Okay, I think I'll go ahead and get some hose clamp pliers and do that as well.