View single post by Mark Rosenbaum
 Posted: 11-20-2005 05:54 am
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Mark Rosenbaum

Joined: 03-12-2005
Location: Kingman, Arizona USA
Posts: 532
Ed's fuel pump looks like the typical Facet / Purolator unit sold by Delta and many other sources.  The one in my car has been working fine for 4 or 5 years now.  It normally rattles fairly loudly but will occasionally become less noisy or even stop clattering entirely, all without any apparent effect on the way the car runs.  It's been doing this ever since I installed it, and the fuel pressure has remained a constant 2.5 psi at the carbs, so I feel safe in presuming this to be its normal behavior.

Upon reading Ed's report, my first thought was that there was debris in the fuel.  A single flake could hold open one of the pump's valves and thus halt fuel flow.  The pump relies on this flow to remove much of the heat generated by its operation, and on good contact with the chassis to dispose of the rest.  If there were no fuel flow, a pump installed in the manner shown by Ed's photo could easily get fairly hot.  Perhaps the pump might even quit working as a result.

This hypothetical debris could easily have come with the purchased fuel.  A gas station's underground fuel tank(s) will rust, often heavily, and their pumps' fuel delivery hoses tend to rot from the inside out after prolonged exposure to fuel blends containing MTBE (which would have been the case in Ed's location).  I would suspect this is why the Facet / Purolator instructions state that the pump should have a filter on its inlet line.

In general, electric fuel pumps don't develop much suction, and the lack of suction from Ed's pump may not be significant.  Also, the Facet / Purolator pump has both a ground wire and a power wire and therefore does not require a ground through the chassis.  (However, as noted above, a good connection to the chassis may be needed to remove excess heat.)

I've attached a photo of my car's pump installation.  The filter is on the pump's inlet side, and there's another in the engine bay, just before the tee for the carbs.  The two 90° elbow fittings were very inexpensive and allow a neat installation.  The green tape secures the pump's power wiring.  The black painted steel mounting bracket I ginned up for the pump is pretty much hidden, but it's there.

What I would do in Ed's position would be (a) install a filter in the pump's inlet line and (b) secure the pump to the chassis via a good mounting bracket.  I'd replace the pump only if it were to quit again once this was done.

Attachment: facet pump & filter.jpg (Downloaded 69 times)

Last edited on 11-20-2005 06:00 am by Mark Rosenbaum