Date:         Tue, 12 Oct 2004 15:14:08 -0400
Reply-To:     David Beierl <dbeierl@ATTGLOBAL.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         David Beierl <dbeierl@ATTGLOBAL.NET>
Subject:      Re: Fuel pump
Comments: To: Mike Miller <mwmiller@CWNET.COM>
In-Reply-To:  <BD90B90C.64BC%mwmiller@cwnet.com>
Content-Type: text/plain; charset="us-ascii"; format=flowed

At 01:26 10/12/2004, Mike Miller wrote:
>But when I measure voltage at the pump it's around 12-13 which is about what
>it is at the battery.
>
>Any ideas of what's going on?  Possible fixes?

Bad connection somewhere, mike...you're losing voltage across a high
resistance.  Problem is worst when the pump is trying to start.  Get out
your voltmeter and find out where it's going, then fix that terminal or
whatever.  *Ideally* you would have full battery voltage across the pump
and none anywhere else, but realistically every wire and every connection
consumes a little.  You can expect to lose a total of maybe half a volt in
the wiring -- more during startup of a motor or other device that draws
high current when starting.

Get someone to keep flipping the key for you, this will be easiest to find
when it's trying and failing to run.  Start by measuring directly across
the pump terminals (if possible the actual spade terminals of the pump, not
the females that are plugged into them).  That will tell you how much
you're losing.  Then check the ground side, see how much is going
there.  Then measure across sections of the +12 wiring.  It's quite
possible that you have several places with excessive losses...

david


>Mike

--
David Beierl - Providence RI USA -- http://pws.prserv.net/synergy/Vanagon/
'84 Westy "Dutiful Passage," '85 GL "Poor Relation"