Author Topic: Fuel pump/ gas tank. 61 Devile  (Read 101 times)

Offline CDW

Fuel pump/ gas tank. 61 Devile
« on: January 08, 2019, 10:05:03 PM »
My mechanic changed my gas tank from the original because he said the fuel pump couldn’t go in the original tank.  The problem is the new tank sits 7” from the ground.  They have to have another option.  Has any one have any experience. 

Offline 6Caddy2

Re: Fuel pump/ gas tank. 61 Devile
« Reply #1 on: January 08, 2019, 11:34:59 PM »
"CDW not to much info as to why you are running a in tank fuel pump ??? I'm gonna take a stab in the dark and say you are running fuel injection?!?

So my help or advice would be put back original tank, and run an external fuel pump, I did after a complete motor overhaul, new fuel lines, cleaned tank, new pickup/fuel sending unit mounted back in original tank and mounted a new electric fuel pump, and drove her 3500 miles round trip from Utah to Texas in June of 2018, without one problem and still running strong, I plan on  switching to the Holley sniper efi system, as I drive this caddy everyday! My research on the efi system that I will run, does NOT require the fuel pump in tank! Here's some photos of what I did!
Hopefully this gives you some idea's or at least food for thought! Good luck!

Offline CDW

Re: Fuel pump/ gas tank. 61 Devile
« Reply #2 on: January 09, 2019, 09:44:30 AM »
6caddy thank you and you are correct I am running fuel injection.  We had the pump mounted outside the original tank.  The problem we had was the pump was so loud you could hear it inside the car.  That’s when the mechanic talked me into the new tank to put the pump inside the tank.

Is your pump extremely loud inside your car?

Offline Dan LeBlanc

Re: Fuel pump/ gas tank. 61 Devile
« Reply #3 on: January 11, 2019, 03:38:29 PM »
If it was loud inside the car, it would seem as if they didn't isolate the mounting points with rubber.  You're getting sound transmission from the pump, into the frame, and in the car.
1977 Fleetwood Brougham - 3x black with Astro Roof
1977 Continental Town Car

Offline 6Caddy2

Re: Fuel pump/ gas tank. 61 Devile
« Reply #4 on: January 12, 2019, 01:27:45 PM »
I isolated the fuel pump with a piece of rubber for the bracket to trunk pan, and a piece inside the bracket, it really deadens the vibration/noise from the pump, I can just barely hear the pump running and the caddy is a convertible.                                   
When I switch to the sniper system I will locate that fuel pump to the frame rail and isolate it in the same manner as what I'm using now, I have a few friends running the Holley EFI system and they have mounted there fuel pumps on there frames and used rubber to isolate the pump and they run very quiet, yes if you are standing outside of our cars you can just make out the hum of the fuel pump, but inside no sound, one is a 62 cdv, and a 65 Fleetwood. 

Offline 62droptop

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Re: Fuel pump/ gas tank. 61 Devile
« Reply #5 on: January 12, 2019, 11:53:42 PM »
cdw,sounds like you need a new mechanic

a fuel tank that low is a recipe for disaster!
I bet it will hit over a speed bump over bottom out during down the road and hit a dip
the original tank is very shallow making it a little difficult to add a electric fuel pump,but our own master Dan (62 Coupe)  has modified his tank for one

there should be no reason a external fuel pump mounted outside the tank to be extremely loud if (1) it is correct pump for application and (2) it is mounted as recommended (and like you actually take pride in your work)
I have mounted many fuel pump and some were a little noticeable, none were horribly bad

some fuel pumps are just noisier than others
1962 Cadillac series 62 ragtop

driven like it is stolen
broken because it was driven(still)