fuel pump check valve question

["Livolsi, Stephane" <livols1@investorsgroup.com>]

Due to hard starting problems, misfires at low speed and failing to
idle, I have been replacing components in the fuel and ignition system
on the 5KTQ.  Working my way up from to the more expensive stuff.
Crankcase breather hose was replaced (fixed major vac leak), new plugs,
wires, rotor and distributor, fuel filter,airfilter.  Michelin man hose
is good

Today I took out the fuel pump.  It runs strong but I have been advised
on this list to check the "check valve" for proper operation.  First of
all, the gas tank looks good inside.  It is bare metal.  I see no
evidence of this "coating" that I have heard about that peels off so
maybe it has already been replaced.  The screen at the bottom of the
pump had a bit of "stuff" on it but very little so no problem there.
When I released the pressure at the warm up valve, I had really good
pressure.  This was after the car had been sitting for a couple of
hours.
Anyway, I disassembled the fuel pump to test the check valve and here is
where someone might be able to help me.  Should this check valve be very
easy to blow through in the direction of fuel flow? or does it need high
pressure because when I blew into it, it was quite difficult to get any
air through.  Also, when I blew against the direction of fuel flow, some
air did get through, but very little.  Should any air be getting through
at all, against the flow?  I didn't use compressed air or anything, just
the good old lungs.

TIA
Stephane Livolsi
180 Yorston St
Williams Lake, BC, V2G 3Z1
ph 250-392-2637
fax 250-392-2693

'86 5KTQ stock (if you don't know what it means, you aren't in the club)