Rick:
The fuel pump is fed by gravity, so there is always a fresh
supply of fuel at the pump. In addition, there are one way check valves
in the fuel pump that insure the fuel can only flow towards the carbs.
I think the reason you get seepage is the temperature cycling
during day and night. At night, the fuel cools and contracts, which
pulls more fuel into the fuel line between the pump and carbs. Then as
the environment warms up during the day, the fuel expands and seeps out
the end of the line (remember that the check valves will prevent the
expanding fuel from returning to the fuel tank).
Unless you have a very good seal on the end of the fuel line,
the increased pressure will force fuel out of the line where you have
stubbed it off. Stuffing a bolt in the end of the fuel line is probably
not good enough, as the pressure will force the fuel past the threads.
Vance
-----Original Message-----
From: owner-6pack@Autox.Team.Net [mailto:owner-6pack@Autox.Team.Net] On
Behalf Of Rick Norris
Sent: September 12, 2007 11:46 AM
To: 6-Pack List Serve
Subject: [6pack] Rust and fuel pump questions
<snip>
The second issue is that I've disconnected the fuel lines from my carbs
as I prepare to remove them for rebuild and there is a persistent drip
of fuel from the front carb's hose. I've lifted the entire apparatus to
a level above the carbs and, indeed, as high as I can get the plumbing
in the engine compartment, plugged the end of hose and, still, there is
this persistent seepage. Is there that much pressure maintained by the
fuel pump? I opened the fuel filler cap thinking that might relieve any
pressure but walking into the garage this morning I got a whiff of fuel
fumes and the end of the hose was/is wet. What's up with that?
Thanks in advance for any assistance, it's greatly appreciated!
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