External Fuel Pump confusion (1979 Eldo)

[T.Skytte]

Hi,

I'm a little confused about (external) fuel pumps for my 1979 Eldorado.

I had ordered a Spectra SP1252 but because they delivered the wrong pump my mechanic sourced another model that looks like a Carter P74015 and installed it.
Looking at Carters website I find it here: https://carter.opticatonline.com/part/bcqs-0-carter-p74015?ctx_bv=2826&ctx_region=usa&ctx_iam=1
This is also the one recommended at Rockauto for this model (1979 eldo): https://www.rockauto.com/en/moreinfo.php?pk=296441&cc=1025941&jsn=415

Only difference seems to be the one installed has a more black inlet/outlet at the top compared to the pic on Carters and Rockauto website (see attached photo).

So far so good.

I noticed the Max pressure on this pump is only 32 PSI and max flow rating is 19 gph (see Carter link).
But compared to Spectra that one has 125 Max PSI (and 115 Min) and 38 gph max flow rating.
Other pumps at Rockauto for this model also have similarly high PSIs.

So the question is: is 32 PSI and 19 gph enough?

Also a curiosity: On the Carter site it says 'in tank' in the specs next to 'In tank or External'. How can that be? At the Product Description it says 'Fuel Pump - Electric In Line'.
So since they obviously write wrongly 'in tank' then maybe the 32 PSI spec is also wrong?

Anybody have any idea about this?

Thanks!

Best regards,
TS

[bcroe]

The 5.7 gas engine runs at up to 39psi, so the external pump
should be capable of at least that.  19 gallons per hour sounds a
little on the wimpy side, not sure of the translation.  I use a 190
L/hour pump, which translates to about 50 gallons/hour. 

Some pumps are designed so they may be mounted either in the
tank or outside, hence the dual rating.  The in tank pump can have
issues and the car still runs if the tank is over half full.  I just pulled
this original 79 Eldo tank unit, note the hose connecting the pump
to the pipe has completely failed. 

There have been problems with 70s EFI dual pumps, noise, excess
current burning out ECU contacts, and all that stuff mounted under
the car.  A couple of us have taken a leap and converted the tank
unit to a high pressure pump.  This minimizes the noise, reduces
current to just one pump, and leaves only an in line fuel filter
in the frame.  A little tricky since all is submerged in gas.  My
pump is a WALBRO 190 (L/hour).

In any case any 70s Cad EFI should have a relay for pump current
added to protect the ECU, described in Dec 2010 The Self Starter
page 24, I also have a kit. 

Another thing I have added is an electric fuel pressure gauge
(old mechanical cannot be trusted).  Can be very useful to
track issues, I use Evil Bay

271992161854    Pressure Transducer Gauge 60 psi, 2-1/16"/52mm, analog voltage input, LED light $35

261508176203  Pressure transducer or sender, 60 psi, stainless steel, for oil,fuel,air,water $22

Bruce Roe