Greetings, 
I don't believe there is, and why should there be ?
Unless something blocks the fuel lines, which I can't imagine ever
happening...
There is no need for any kind of fuel pressure relief valve.

I don't know why anyone would do this 'test' that you did. The fuel pump was
just responding like it should.

 In the over all scheme of taking care of your vanagon, I don't think this
was a wise thing to do, unless you intentionally are checking for
weakness.....like a hose clamp not tight enough or something like that, or a
hose about to fail. 

  It just does not seem like a kosher, or safe, or wise thing to do, to go
pinching off fuel lines on a running engine.  You could cause a problem were
there wasn't one in the first place at all. 

< btw, this is why I had to bail on this list a few years ago - I see some
of the most amateurish,  uninformed things here. It IS very educational
though, thanks for that ! ....learning what people 'make up' in their minds
to do on vanagons - and I don't mean to be harsh, but it is scary at times !
) 

smiles, Scott
www.turbovans.com 

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Sam Payne
Sent: Friday, July 20, 2007 1:17 PM
To: vanagon@GERRY.VANAGON.COM
Subject: fuel pump relief valve?

Does anyone out there know if an '86 vanagon fuel pump has a built-in
pressure relief valve? If it does, what should maximum pressure be before
the valve opens? I found no mention of this in Bentley.
     I pinched shut my fuel return line expecting to see pressure relieved
at about 80 lbs. but it climbed to 100 before I released the hose, worried
about popping a line off or damaging the system. Seems to me there must be
a relief valve since it's common in other FI systems.

                            Thanks for your help,   Sam