Fuel Pump Check Valve...

[Stowe, Ted-SEA]

something like this exists, In fact I am trying to find a one-way check
valve myself for my v8 xj6. I had a mechanic put some of those on my 911
once when I had a hot starting problem.
If you find a source for a one way check valve please let me know.

Ted.

-----Original Message-----
From: Kurek, Larry [mailto:lkurek at anl.gov]
Sent: Friday, April 30, 1999 7:50 AM
To: 'DIY EFI Main List'
Subject: Fuel Pump Check Valve...


Another quick question for you guys... :)

Anyone know of a source for an inline, high pressure check valve...in either
a 5/16" or 3/8" (dual barbed), or -6AN? Reason I am asking, is I have an
older (about 8 years old) Bosch pump (that used to be sold by Accel for
applications up to 420HP) on my 67 Camaro TPI, that had a few problems. I
think the pump was built before they had any idea that MTBE and other such
nasty additives would be added to fuel...so they used plain old buna-N
O-rings to seal the pump internally. Well...when I was moving the car around
a bit ago...I noticed a nice stream of gas pouring out the back of the
car...about where the pump was (with maybe 300-400 miles on the pump).
Knowing that raw fuel dumping on my hot exhaust system was not a good thing
;) I immediately shut down the motor and verified it was the pump. After
quickly moving it back onto my lift, I pulled the pump and noticed the gas
was coming from between the outer housing and the pump outlet housing end
plate (?), right around where the crimp is. So..I undid the crimp, and
pulled the pump apart. There are two O-rings which seal the suction from the
pressure side and the pressure side from the outside of the pump. Both were
hard as rock and cracked...hence, the leak. So, I replaced them with Viton
O-rings, put the pump back into the housing, put down a nice bead of epoxy
around the housing and end plate and rebent the crimps down. Well...I should
have checked the check valve as well...since it also is a rubbery material.
I guess it leaks as well, since after I had the pump together, I could blow
through the pump both ways...although backwards WAS harder, it didn't seal
:( . I did verify this with a pressure gauge as well..when I put the key to
on, the pump runs for a couple of seconds and the pressure rises nicely to
42psi. As soon as the pump shuts down, the pressure drops...takes maybe 3-4
seconds to drop back to zero. Since the check valve is in the outlet of the
pump, and this particular one cannot be pulled from the outside, I need to
rig something up to maintain my fuel pressure for startup purposes. Any
ideas?

TIA!!

Larry