56 Fuel pump

[dplotkin]

My 10 year old Airtex pump failed today on my 30th anniversary and a day after I buried my Mother from this virus. So stay safe. I cannot find a replacement anywhere. What is the best electric in line pump to use?

Dan

[Lexi]

Dan so sorry to learn about your Mom. Although we have never met, I feel that we are all family here. Let us pray that she is now in a better place.

Regarding your fuel pump, on my '56 I installed a "Spectra Premium SP1025". Mine came with a steel cased fuel filter on the inlet side. I only use mine for back up & starting after sitting for long intervals, as my mechanical  pump is still operational. I have switched it on for long periods when driving, (has it's own separate line), and was fine. A buddy of mine who owned a '56 Caddy used the same pump exclusively on his ride (he removed and blocked off the casting where the mechanical pump had been mounted). So he drove for years with this pump only, on his car. So I am safe to conclude that this pump will work for you, on a stock 365 V8.

If you have trouble locating it, I still have the box and could post a photograph of the SKU if needed. I paid around $148.00 Canadian for this unit about 3 years ago. Hope this helps at this sad time for you.

Clay/Lexi

[Jon S]

Likewise so sorry to hear your sad news about your mother. Rock Auto is currently out of stock for the Spectra Pump you need ( pictured below).  I was curious if anybody knows if a 1957 to 1962 Mechanical Fuel Pump will work on a 1956 as opposed to going to electric pump?   If so that would be a very simple replacement.

[cadman56]

Dan, so sorry to hear about your Mom.
I purchased rebuild kits from Terrill Machine for my pumps and used Airtex E12S (? or E8012S) electrics as backup or start up only.
Larry

[dplotkin]

Gentlemen, thank you for your kind words. Stay safe please. As for my Fleetwood...the pump was fine. The pump push rod is fine. The push rod travel is to spec. The tank and lines were replaced 10 years ago. There is fuel in the tank. We can blow air through the line to the tank. We can suck gas up from the tank with an electric pump. But we cannot get either fuel pump to pump enough fuel for the engine to run. The engine otherwise runs fine. The car has run fine for 10 years and ran fine until the moment it didn't. The only thing I can think of is the rubber hose to the pump. It blows fine, maybe that's it?

Dan

[35-709]

Maybe so.  Deteriorated rubber hose can suck air, it can also fail internally blocking passage of fuel or whatever it is supposed to be carrying.  Often seen with rubber brake line hoses, I had one fail internally that fed vacuum from the carb to the brake booster.  Would be fine when cool, but as the temp rose in the engine compartment the hose would swell internally blocking off the vacuum to the booster causing a hard pedal with a lot of effort to stop the car.  Hose appeared to be fine on the outside.

[Lexi]

Hello Dan. Don't know if this helps, but I believe the following specs for volume output for the mechanical pump should also be consistent with an electric one. If so, read on. A mechanical pump on a '56 Cadillac stock 365 V8 engine should:

Fill a 1/2 pint bottle in about 9 strokes, at cranking speed.

At idle, pump should put out 1 pint in 45 - 60  seconds.

Vacuum intake side at idle minimum 10 inches (think this number is correct).

Pressure at outlet side should be between 3 -5 PSI.

Push rod length as per Shop Manual 7.1425 - 7.1475 inches long.

Fuel stroke is .245 - .250 of an inch.

If your electric pump and other related equipment meet these specifications, then start looking elsewhere for problems. Like a clogged fuel filter, inline or even the mesh filter (if still there) at your carb inlet. Other issues inside the carb itself or a vacuum leak (as G. Newcombe suggested). Hopefully this can help narrow the issues for you. Clay/Lexi

Edit: You need that very useful old car diagnostic tool, a vacuum gauge with a fuel pump indicator on it, to assist in this troubleshooting.

[dplotkin]

I will now disclose the following problem solved to encourage those who are confounded to take a hard look. The new pump was clocked 180 degrees and my shop was asking the pump to suck from the Carb. Old pump had failed, new pump in place and I pick her up tomorrow.

Thanks everyone

Dan

[35-709]

Rotfl !!