IslandVette808

Is there another way to relieve the fuel pressure when the engine's in pieces? I know its kinda a big over sight but I completely spaced it and now not sure how to go about it I'm thinking of slowly loosening the nuts on the fuel lines just enough to start letting pressure out. Would this be advisable? Im changing out the water pump and removing all things emission related on the 85. Thanks for any help!

Calderone

what mods are you doing ? from what i know,just remove the fuel cap

MK 82

Here we go again!

FICINJECTORS

to release the pressure from the rail. Just push the schrader valve thats located on the rail.
do it over a pan, make sure you get the nose up higher than the tank. then remove the lines from the rail and cap them,,

chevylu

Unless you want a puddle of gasoline under your Vet:
. Disconnect your battery
. Remove the gas cap and leave it off until everything is back together

Ask me how I know this . . . .

Ed Ramberger

Perhaps you could have simply offered the advice of pressing the schrader valve on the rail...

IslandVette808

Well according to the haynes manual the fuel lines have to be disconnected to remove the ac compressor bracket when changing the water pump. Is there another way to do this without removing the feull line? I forgot to relieve the pressure before taking apart so that's why I'm asking.

Calderone

i've just did the injector swap (3 days ago)
and i did relieve the pressure opening the gas cap...
when i unhooked the fuel lines,it dropped a bit of gas,nothing
that a rag can't absorv,too little,nothing that will leave your engine
all wet in gas,i put them back together and that was it.-
No big deal bout this ...

FICINJECTORS

there is no relationship to the pressure in the "tank" vs pressure in the "lines" the pressure in the tank is for the EVAP system which takes vapors from the tank and runs them through a charcol cannister and is reintroduced into the intake manifold to get mixed with the combustion mixture to get reburned instead of being released into the air as in older cars that had vented gas tanks. The pressure in the fuel rails is a result of the fuel pump pressurizing the system through the lines with the regulator holding the pressure at 43.5 psi. The rails hold a small amount of fuel so take off the tank cap because the pressure in the tank can push fuel through open lines, jack up the front to raise it above the fuel tank so you don't siphon the tank and push the schrader valve on the rail over a pan. It will take about 3 seconds to release any pressure (if any) then remove the fuel lines and cap them off. This is no big deal.

chevylu

I’m here to tell you that you are absolutely wrong about this under certain conditions and that your advice has the potential to cause a very serious fire hazard.

If the fuel tank is subject to an increase in temperature such as being exposed to the sun in the afternoon and the fuel cap is on, pressure will build in the tank. If the fuel lines are disconnected and not unconditionally capped the pressure will result in a fuel discharge.

It is a very big deal!

larryfs

I never capped the fuel lines. I just made sure they were higher than the engine. Never had a problem.

Let's say I wanted to cap them.
what size caps should I buy?
are they metric, or SAE?

Calderone

It's a very big deal if it catches fire,but how ?
How it's gonna catch fire ?
I told him before,better remove the fuel cap,and then follow FICINJECTORS advice,you should have no problem,of course it can cause a fuel discharge but ,not an explosion.-

MK 82

Please explain to us what was wrong with Jon's advice. He said to leave the cap off.

FICINJECTORS

I don't know exactly the size.. i have made a set of caps from a old fuel rail Its now a tool I use when working on TPI. I cut the tubes leaving the fittings and put vac plugs over the pipe ends.. did it like 20 yrs ago. You can always raise the lines but being safety minded i do not leave fuel lines open, too many cats. Most people don't have a problem untill its to late.

FICINJECTORS

what is'nt a big deal is relieving pressure of the fuel rail. If you read my post I said to take the cap off. My instructions were right. The OP seems to be afraid of this whole process. All I was doing was trying to tell him that it's no big deal to do what he needed to do. My advice was fine.

janarvae

5/16" vacuum caps (readily available at auto parts stores) have been on my fuel lines for a month or more with no leaks (battery is disconnected and gas cap is off) and there was no fuel leaked when I unscrewed the lines from the rails, BUT, there was fuel still in the rails.