PA28/38 Fuel Strainer Drain Check
 

Concerning the preflight check of the fuel strainer drain and checking for water etc., nowhere in the Flight Manual/POH is any mention made of switching the electrical fuel pump ON for this check, although some pilots seem to feel this is necessary. Indeed the fuel pump is downstream of the fuel strainer so can anyone tell me how switching the electrical fuel pump on will enhance the flow of fuel from the fuel strainer?

Interestingly though the Flight Manual/POH does mention that this check should be made on both left AND right tanks.

Thanks for any help.

ffb,

Im assuming you are talking about the main fuel tank strainer (under the wings) check in which case the fuel pump has got sod all to do with the checking of the left and right fuel tanks for any water.

There is unlikely to be any water collected between the main tanks and the engine, unless it has been taken from contaminated fuel in the main tanks. The main check to worry about is making sure there isnt any water present in BOTH L and R fuel tanks. Most likely to be found first thing in the morning after sitting all night, or if the aircraft has been parked up for a while.

Hope this helps you!!

Gascolater check
 

There's also the drain on the gascolater to check, just forward of the port wing leading edge. You won't get a flow here unless the fuel selector is selected to a tank - some pilots turn it to'off' after a flight, so check it's got the LOWER tank selected (ready for startup)

An essential point with all these tank drains (we've got FIVE of the little darlin's on our PA28-151) is to make sure they're seated back properly once you've done the check. We had to buy an expensive new tyre when one dripped onto a wheel and ruined it. Even more critical is the aforementioned gascolator drain. A serious crach has occurred in the past when the engine failed on takeoff due to some of the fuel leaking out of here...

The Odd One

I suspect that The Odd One has hit the nail on the head. It's not the fuel pump you want turned on, it's the fuel tap. I've (accidentally) tried to strain the forward gascolator on a PA28 (the one described by TOO) with the tap off. Nothing comes out at all.