fuel pump question

[DH Comet]

My '53 Manhattan has been running on an electric pump only for awhile and it has just quit.  I'd kind of like to go to a mechanical pump, perhaps with a free-flow backup electric, but I'm having trouble finding a single-stage mechanical pump.  Can I put a double-action pump on the car, even though it only needs a single?
Does anyone know of a single-action pump that's available these days?  And, for that matter, a good free-flow electric one?  Other threads on this topic are pretty old.

[MarkH]

I'm not familiar with your model, no doubt others here will know much more. I did have my pump rebuilt here http://www.then-now-auto.com/ very well done, and some axle bumpers vulcanized. The owner happened to mention he had quite a large inventory of vintage pumps at the time. Might be worth a call.

[Doc]

Rudy Phillips 2017 catalog:
51-54 Kaiser single action fuel pump - P/N 209983 $105 with $65 core.
http://circlekf.com/vendor/RudyCatalog2017.pdf

You can find an electric pump at NAPA, E8011, I think, but check it is 6 volt and not 12 volt. It's an easy in-line installation. Carter also offers quiet electric pumps.

[joefrazer]

I've had two pumps done by then-and-now and I have a third on its way. They do great work and when the pump arrives, it needs nothing more than installed. They're reasonably priced as well.

[Doc]

I also have used "Then-and-Now" for at least two fuel pump rebuilds. Turn-around was very quick.

[DH Comet]

So if you have a mechanical pump running it doesn't mind being "pushed from behind" when you turn on a backup electric pump?

[Corsairdeluxe]

Carburetor flooding is most likely with both running in series.

[Doc]

Electric pump typically only used for priming after long down times or in case of the dreaded vapor lock. I have pressure regulators on mine.

[DH Comet]

So I'm going to try running mechanical only.  Not that I keep track of it particularly, but is there a fuel consumption difference between all-mechanical and all-electrical?

[kaiserfrazerlibrary]

I had an electric pump discretely hidden in the rear axle area because of vapor lock issues.  I did not notice any difference in fuel economy. 

The problem is today's gasolines.  Removal of various additives (including tetraethyl lead) and substituting more enviornmently friendly compounds resulted in lowering the evaporation point of the product.  Old (and new) cars that never had the problem before were falling prone to vapor lock.  When the Saturn SUV was under development in the 1990's it ran fine under all kinds of conditions at GM's Milford proving grounds but locked up when sent out to the Arizona facility for desert testing.  By modifying the mounting of the fuel rail to the engine we found out that the air flow under (with modification) and over air circulation, the temperature at the rail was reduced 45 degrees.  This, and the normal 60 psi fuel pressure in the casting was enough to keep the gas liquid and get rid of the vapor lock.  In older cars like ours, the extra pressure of the electric pump (around 8psi compared to the around 4-5psi on the mechanical pumps) keeps the fuel bubbles moving and increases the fuel flow into the carb and that helps reduce the vapor lock risk.

[DH Comet]

So the mechanical pump is on now (thanks for supplying the part, Chris!) and I like it.  The car just feels better somehow, and it doesn't have that subtle electric sound that always seemed wrong.  It's running well - I think it likes being all mechanical again!