Schraeder valve

[maddzz1]

i thought you were supposed to release the pressure in the system using the scraeder valve before disconnecting the fuel filter or anything else in the fuel line. But after reading the thread about the guy who put 2 stroke gas in his MJ i am a little confused.

 

Do I push in the scraeder valve and drain the gas from the fuel rail to relieve the pressure before changing the fuel filter? or do I just disconnect the line from the filter first and that relieves the pressure?

[mvusse]

I think the safer way would be to disconnect the line at the filter, Just keep the gas aimed away from your face, and away from the (hot?) exhaust. It'd be best for the environment to catch it in a pan.

[Geonovast]

I think the safer way would be to disconnect the line at the filter, Just keep the gas aimed away from your face, and away from the (hot?) exhaust. It'd be best for the environment to catch it in a pan.

 

If you have a fuel pressure gauge with a bleed off hose attached using the valve would be a lot safer. Then you bleed it into a container at the rail, and you don't have to worry about it spraying all over your face and arms 10 seconds after you decided to put on safety glasses while you're under the truck disconnecting hoses...

[maddzz1]

So once the fuel is drained from the rail the line is no longer pressurized?

[CWLONGSHOT]

So once the fuel is drained from the rail the line is no longer pressurized?

 

Yes...

 

Don't be surprised to find little to no pressure. ours are old vehicles and the pressure can "bleed" off on its own.

 

CW

[Eagle]

The Schraeder valve can be used to bleed off fuel pressure. Keep in mind, I wrote "fuel" pressure. If the line has been pressurized, you're not letting out air, you're squirting gasoline. You can put an absorbant rag there to catch it, or try to direct it into a container. Yes, it's probably more controllable than disconnecting a pressurized hose at the fuel filter underneath.

 

The post with which I took issue earlier today referred to using the Scraeder valve to bleed off 'air" -- after having been trying to start a truck that isn't cooperating. That's a good way to spray gasoline around, and gasoline squirting unexpectedly has a way of seeking out anything hot or glowing and starting fires.

 

I wasn't suggesting that the Scraeder valve should not be used as intended. I just wanted to cauthion that it should be used as intended, and not carelessly by people who don't understand what's supposed to come out of it.

[bpm4x4]

couldn't you also remove the fuel pump relay (or fuse) with the truck running and just let it die?

[Pete M]

I imagine that would work too.

I just put a rag on the valve and push it with a screwdriver. A small amount of gas squirts out and you're done.

[chicofuentes0224]

i thought you were supposed to release the pressure in the system using the scraeder valve before disconnecting the fuel filter or anything else in the fuel line. But after reading the thread about the guy who put 2 stroke gas in his MJ i am a little confused.

 

Do I push in the scraeder valve and drain the gas from the fuel rail to relieve the pressure before changing the fuel filter? or do I just disconnect the line from the filter first and that relieves the pressure?

 

I disconected the line at the fuel filter and 2 oz of gas might have come out. Then again I had very little gas in the tank to begin with. Just put some bucket underneath to catch any thing that comes out.

[UNL1MTD]

couldn't you also remove the fuel pump relay (or fuse) with the truck running and just let it die?

 

That is the FSM recommended way to do it for my LJ '05. However it is not effective if the engine is hot/the vehicle has been driven for the last half hour. Basically there is enough gas vapors in the return line to keep the motor going at a terrible idle. Its ugly. So if you do that, just make sure the vehicle is cold.