FE-FC Holden Discussion Forum

Technical Board => Modification Help => Topic started by: Old_Mt_Isa_Boy on April 21, 2013, 11:12:26 AM



Title: Electric fuel pump for the grey motor
Post by: Old_Mt_Isa_Boy on April 21, 2013, 11:12:26 AM
Cannot find a direct reference by searching. Any suggestions for the type and size (PSI etc) of an electric fuel pump for my grey motor. I'm over it not starting already if I don't start it every week.

Regards

Wayne b



Title: Re: Electric fuel pump for the grey motor
Post by: Harv on April 21, 2013, 01:48:51 PM
G'day Wayne,

I'm guessing that after the car sits for a week, you have to crank it over forever to get it to fire? This could be due to leakage (the drips from the carb can be subtle), or could be the fuel bowl evaporating over time, leaving the carb dry (the fuel bowl vents to the carb throat, which in turn vents to the air cleaner and from there to the engine bay). Mine does the same thing, though takes about a month to dry the bowl. As a quick check, I'd suggest letting the old girl sit for a week, then take off the carb air horn and visually confirm the bowl level is dry.

If your fuel pump is on it's way out, it can take forever to reprime the bowl. You can check the pump with a tee-piece and pint glass (as per the workshop manual), but this is not so easy if you still have the original steel fuel lines (easier if they have been replaced with rubber hoses).

An electric pump may not help the issue if it is "loss of fuel bowl level over a week causing hard starting". The stock factory pump will prime the bowl pretty quick even from stone empty.... not much slower than an electric pump. The electric helps you out by being able to switch it on before starting the engine. This is fiddly - you need a fuel pump switch in the cabin. It is also reccomended to use an electric cutout that stops the fuel pump with low oil pressure or loss of ignition (Peel Instruments makes a black box, commonly used in LPG conversions). Add to this the power and mounting for the electric pump and the noise fro th electric pump, and the pain-in-the-bum factor gets pretty high.

If it was mine and I was determined to replace the fuel pump, I'd buy one of the new red motor mechanical pumps available. Not much help if you are running a vacuum pump admitedly  ;D

If you do absolutely want to go electric, the info below (culled from the Stromberg and Holley 350 Guides) may be handy:

Stromberg carburettors operate on approximately 2½-4½ psi of fuel inlet pressure (SUs are happy to run on 1½-3½ psi and overflow around 5 psi, and 350 Holley carburettors run happily at 5-7psi). Too low a fuel pressure and the fuel level drops in the bowl. Too high a level and the needle and seat is forced open, flooding the engine. This is a particular risk when the original Holden mechanical fuel pump has been replaced with an electric inline pump – see chart and table below. When using inline fuel pumps (notably Holley), a pressure regulator is mandatory to prevent flooding.
Fuel Pump   Maximum Pressure (psi)   Free Flow (GPH)
Facet SS208   3½   14
Facet SS171   3½   14
Later Holden (blue motor steel can)   3.9   9½
Facet SS500   4   25
Facet 60104   4   25
Facet IP002   4   32
Early Holden (grey/red glass bowl)   4½   9
Facet SS148   4½   24
Facet SS501   4½   30
Facet SS165   5   15
Carter GP4600HP   5   100
Facet STS504   5½    30
Facet IP007   5½    36
Facet IP131   5½    36
Facet IP220   5½    36
Facet 60106   6   32
Facet SS135   6   34
Carter GP4603HD   6   43
Carter GP4070   6   72
Facet SS502   7   32
Facet STC505   7   35
Facet IP051   8   30
Facet RTW506   8   40
Facet BTP001   8   40
Facet BTP001   8   40
Carter GP4594, GP4389, GP4259 and GP4602RV   8   72
Facet SS200   9   32
Facet SS503   10   34
Facet 60107   10   34
Holley Red   10   100
Facet SS185   11½    29
Facet 40222   11½    33
Facet 40223   11½    33
Facet 40237   11½    33
Carter GP4601HP   18   100
Holley Blue   18   110
Holley Black   18   145

Cheers,
Harv


Title: Re: Electric fuel pump for the grey motor
Post by: Old_Mt_Isa_Boy on April 21, 2013, 02:08:36 PM
I agree Harv and will keep the mechanical. Certainly appreciate your speedy response. Was ready to hit the buy button. ;D

Regards

Wayne b


Title: Re: Electric fuel pump for the grey motor
Post by: pedro on April 22, 2013, 05:11:24 PM
G'day Wayne, have to agree with Harv there must be another issue as it shouldn't be hard to start after one week, the fuel bowls shouldn't be empty after that short a time and even if they were a few turns of the crank should put enough fuel in to start the old girl, did you replace your fuel pump when you did the build.
              Pedro


Title: Re: Electric fuel pump for the grey motor
Post by: Old_Mt_Isa_Boy on April 22, 2013, 08:51:28 PM
It was replaced. Spoke to an old matetoday and heagrees with you, it must be leaking. Will look at this weekend.


RGds Wayne b


Title: Re: Electric fuel pump for the grey motor
Post by: FCRB26 on April 22, 2013, 09:19:33 PM
Mine does this anything after a week and its winds for a while.
when i did the electronic ign conversion it stopped doing it.
When the electronic ign shit itself after a week it started doing it again?
Just a thought


Title: Re: Electric fuel pump for the grey motor
Post by: GOA350 on April 23, 2013, 09:06:22 AM
I wouldnt think it would be such an issue to turn the engine over a fair few times before it fires because you are getting oil pressure up to the rocker gear and other places before ignition which isnt a bad thing.


Title: Re: Electric fuel pump for the grey motor
Post by: newman on April 23, 2013, 11:52:05 AM
I wouldnt think it would be such an issue to turn the engine over a fair few times before it fires because you are getting oil pressure up to the rocker gear and other places before ignition which isnt a bad thing.

Good point ;) although I ended putting an electric fuel pump on my 36 Ford (flathead of course) as a back up, because it's not an everyday driver I found it took some winding over before she'd fire up. I put the electric pump on set up through a toggle switch, hit the switch, let it tick away for a minute then hit the key and away it goes, turn the electric pump off and drive away ;D ;D ;D I guess it makes it easier for the mechanical pump to do its job after sitting for a few weeks.

Mick 8)


Title: Re: Electric fuel pump for the grey motor
Post by: ACE on April 23, 2013, 06:49:19 PM
One of my cars has a inline primer pump from a outboard motor tank fitted where the flexible hose goes before the fuel pump.
The original owner fitted it years ago.
Works great ;)
ACE  8)


Title: Re: Electric fuel pump for the grey motor
Post by: Old_Mt_Isa_Boy on April 23, 2013, 07:24:44 PM
Thanks guys more to think about.

Regards

Wayne b