my 89 wouldnt start. i found water in gas doing pressure test, how do i flush out the system?????????????????????????

 

since you don't really know how much water is in the tank you have a couple options buy a hand pump from an auto parts store and pump the tank. then fill the tank with good premium fuel with some alcohol also. 2nd option is seafoam the tank and hope that evaporates the water

 

Sounds like the drain line in the rubber boot around your gas cap is plugged. When it rains or you wash your car, water goes in thru the gas cap.

 

first thing i checked was the fuel cap.there is some rust but you can see that the o ring sealed good. a gm tech i know told me the tank should come out. im going to lay down under the back of it and think.

 

I don't know why the tank would have to come out.. Just decide which of the 2 answers above you want to use and do it..If it were me I would start with using the Dry Gas to try to evaporate the water out, then if that doesn't work pump the tank out, but theres no need to pull the tank.Just make sure you clean out the drain hose before it happens again...WW

 

what do you mean by dry gas? i know premium has alchol in it.

 

The water doesn't enter through the O ring where the cap screws on, it enters through the vent valve.
That vent valve is supposed to close when there is positive pressure in the tank, but open when the car cools off to prevent collapsing the tank when the temp falls.
Say you go for a 30 minute drive.........
You park your car, and decided to see if there was any pressure in the tank. You shut the car off, and open the gas cap. you are greeted with warm gasoline vaporous air.
Where did the heat come from? well, other than the exhaust heat surrounding the gas tank, the heated engine might vapor lock if you didn't get the hot gas out of the engine compartment.
Soooooo
The fuel pressure regulator bypasses some fuel to the tank to eliminate gasoline from heating up to the vapor point, creating a bubble of warm air stopping the flow of gas. THen that hot gas goes back to the tank, elevating the tank temp.
Then your car sits for 3 hours. the heat in the fuel dissipates and the gas cools down, and the air in the tank contracts, and if the cap didn't let in air, the tank would collapse.
Say you washed your car instead of let it sit and go watch a movie on the DVD.
You hose off the car, and soap it down. You fill up the boot with water and it doesn't drain fast enough. The tank cools off, and now the cap sucks in your soapy wash water.
That's how it works.

 

go to the parts store and get (heat) i think thats what its called. its a alcahol gas additive.

 

I new it went in the cap, and I new it was vented, but I didnt understand thats how it worked.

Thanks Coupeguy I learned something already this morning. At my age, hopefully I can remember it.

Mike

 

thanks guys