Can't comment on whether your pump should tick constantly or not, but fuel
overflowing from the carbs is definitely wrong (and dangerous). The usual
cause is dirt in the float valve(s) preventing them from closing (which
incidentally will cause the standard SU pump to stop ticking), but with an
after-market pump it could be excess pressure - the pressure at the carbs
should not exceed about 2.5psi. Dirt in the valves can usually be cleared
by disconnecting the 12v supply to the pump and letting the engine run till
the float bowls empty and the engine stops, then reconnecting the 12v to the
pump. The resulting rush of fuel into the float bowls through the (now)
wide-open valves usually clears any muck, but if the problem keeps happening
you need to investigate why i.e. dirt in the tank or excess pressure.
No factory MGB had recirculating fuel, although smogged cars had the carb
overflows routed to a charcoal cannister in the boot, which could hide
overflows.
PaulH.
MG Cars Webring MG Site of the Month - September '99
http://freespace.virgin.net/paul.hunt1/
(or if that URL doesn't work try )
(http://194.168.54.52/paul.hunt1)
-----Original Message-----
From: Tyson Sherman <mts3@ra.msstate.edu>
To: MG Mailing List <mgs@autox.team.net>
Date: 17 September 1999 23:07
Subject: 76 B - fuel pump
>For three years, my B did fine with its
>aftermarket fuel pump. It was installed by a
>previous owner, so I don't know a thing about it.
>
>Recently I converted from the original single carb
>to dual HIF4s.
>
>My crazy fuel pump was of the variety that
>seemingly doesn't stop pumping. It would always
>tick so it seemed, though sometimes it was louder.
>
>Now with the SUs, if I leave the ignition turned
>to 'on' and the car not running, the fuel pump
>won't stop ticking. Sometimes gas will spew from
>the front carb, usually out of the float bowl vent
>pipe.
>
>Is there any way to tell if this is the pump's
>fault or a stuck float? If I did the same thing
>(let the pump tick w/the car not running),
>sometimes the Z-Stromberg carb would flood.
>
>I haven't driven the car yet; it has high idle
>problems as well as other needs, but it will idle
>for a long time like this (not leaking gas).
>
>--
>Tyson Sherman
>mts3@ra.msstate.edu
>ICQ# 10494960
>http://www.tecinfo.com/~tsherman
>
>
>
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