fuel pump check valve(s) dilemma

Phil Rose pjrose@frontiernet.net
Mon, 30 Jun 2003 10:49:09 -0400

I'm just getting around to trying to fix the hot-start problem in our
red car ('91 200q), and I intend to replace the fuel pump's
check-valve. The pump itself seems fine (very quiet). But when I
looked closely at the new (replacement) check valve, I realized there
would be a fitment problem...

There evidently are two different versions of check valve used on
Bosch/Audi 60 mm fuel pumps--the difference involves whether (or not)
an external pressure damper is used. The original oem pump in my car
has a 60mm dia. pump with a pressure damper installed above the check
valve (443 906 093). This check valve is elongated to enable use with
a banjo-style fuel line. However some 60 mm pumps claim "requiring no
pressure damper". Instead, they use just a 12 mm cap nut that allows
the fuel line banjo fitting to be connected via a *shorter* version
of check valve (034 965 093).

The problem is that I was sold the shorter version of the check valve
(034 965 093), and it cannot be used to replace the original check
valve (443 906 093)--unless the pressure damper is *discarded* and a
12 mm cap nut (not supplied, BTW) is used in its place. I am very
hesitant to dispense with the pressure damper, since I am not
replacing the pump, just a leaky valve. I assume I need to find the
proper check valve and not use the short one. Has anyone else
encountered this situation? I don't recall any discussion of this
(the 20V list commonly focuses on the issue of 43mm vs 60 mm pump)s.
Will the cap nut arrangement (i.e., without a damper) work fine with
my old pump? I assume/hope the "long" valves are still available but
have not yet located one.


Phil Rose				Rochester, NY USA
'91 200q	(140K, Lago blue)
'91 200q   (64K, Tornado red)			mailto:pjrose@frontiernet.net