Electric Fuel Pump to Prime carb after car sits for period of time

Be careful - most of the electric pumps are much higher pressure - up to 60-70 Psi. You would have to run a pressure reduction and bypass set up.

You will be lucky to find one that is in the 5-7Psi seat pressure limit range for a conventional carb. I have not seen one.

Thanks Percy, I've found a couple that max to 5.5psi. Facet makes one but would prefer to hear if someone has already done this to their Pantera before proceeding. Thanks again!

I have all my cars set up this way, so never a problem with starting after they set for a length of time. Airtex makes a number of inline pumps with different pressure settings (available on Amazon). Choose one with 12 volts and 3-5 psi. On the Pantera, I installed it in the line between the tank and the mechanical pump. These pumps are designed to have fuel pulled through them by the mechanical pumps, so I have a toggle switch under the dash and turn it off after the cold start. If I should ever experience vapor lock in hot weather, I can turn on the electric to boost the fuel flow.

Holley Red pumps are designed for carbureted applications. I run one on my car. No issues

Thanks to both DWR46 and Tajon. Much appreciated. I was thinking of mounting switch on the console back by the cig lighter for easy wiring?, or toggle as suggested under dash. Thanks again, Ron

One last question if you don't mind. Did you mount high on the firewall close to where the fuel line comes out of the tank sending unit? Or, lower to the bottom before the gas line goes into the mechanical gas pump? Any photos would be much appreciated on mounting location. Thanks

A buddy likes to quote pumps pump.  The don't suck...  Mount it low.  There's enough room to run the lines behind the gas tank shield and there's enough space under the tank for pre and post fuel filters.

Ron: The Airtex pumps are "inline" and, in the case of the Pantera can just be installed in the line from the tank to the pump. As I recall, it is quite short and easily supported the weight of the pump by making sure the line was secured at a couple of places along its travel. The Airtex pumps come with a Pre-filter, and you can remove it if you already have a good fuel filter in the system. This gives you a few additional inches to work with in the relatively tight quarters.

Rick, pumps & pumps for sure, nice setup. thanks for photos!

DWE46, I ordered an Airtex pump so should have no problem with setup. Thanks again!

I'm set up this way, i.e., an inline prime pump using the red Holley. A week to 10 days is all you will get without evaporation. Just turning the ignition switch to run primes the carbs, then when they are full, the pump shuts off.

I'm using the "electric fuel pump" feature on the Haas' Pantera-Electronics Ignition Controller that shuts the pump off when not needed while the car is running.

Jon is a bit of a genius, but don't tell him I said so. I'll never be able to deal with his ego.

Mine is located low, below the tank on the chassis along with a Fram canister filter. That was easiest access for me, under the car, rather then on top.

The fuel line is run between the tank and the shield to a red Holley regulator on the firewall, then to the Webers. The system is set to run 3 psi at the carbs but can be dialed up at the regulator on the firewall. So far I haven't found this necessary but haven't done any track days with the car yet.

There is an electronic fuel pressure gauge sender plumbed in that you can see here half way through the stainless fuel lines in the back. There are lots of combinations that you can go to but the threat of heat sink and vapor lock isn't down low near the pumps, it's up high so you need to have lots of "air" circulating around the lines.

You can see that gauge in this picture of the dash at 3 o'clock through the steering wheel spokes.

Is that a paddle shifter arrangement on the dash ??? Or are they for something else ?

Sorry Steering wheel spokes ...

The red buttons? No. The one on the right is my engine start button. The one on the left is still vacant and available for use. I just haven't found something to use it for yet. They are attached to the steering wheel's rotating hub and run through a commutator.

Thanks PanteraDoug... Beautiful setup ....what a beast! I'm putting my elec. pump low on the frame, Still not sure where to mount the no off switch as only going to use for prime then shut off. I guess to be safe will tie into ignition switch with a relay. Was thinking of putting close to the cig lighter and but not enough amps on the cig wire. Also, it's a hot wire all the time... thoughts? Thanks, Ron

Mine is controlled by the Ignition Controller which "ramps" the EP down once the car is running.

Just turning the ignition to "run" without starting it and giving it a few minutes for the carb floats to adjust after a long time off and not running, is fine for me.

Webers don't have the same issues with drying out the gaskets like Holley's do since the reservoir is cast into the bottom portion of the carb. You just need to verify that the inlet valves aren't stuck and if you switch away from the Viton seat valves to the glass ball valves that 99% likely eliminates that issue altogether.

As you can see by the interior shot, I did a lot of work cleaning up the mess on the console and dash.

I just had a traumatic experience in finding a nice location for the electric parking brake switch location. It took me weeks to decide where to put it.

It eventually went into the location for the instrument panel dim switch which par for the course, after ONLY 50 years, kicked the bucket.

4460 isn't a beast. It's just misunderstood and needs nurturing, sensitivity. acknowledgement of it's sophistication and potential. Is that too much to ask?

Ron: My memory is a little sketchy, but I believe we found a wire that was hot with the ignition ON in the area of all the relays under the drivers side kick panel. We took our power from there and mounted a toggle switch under the dash to the left of the steering wheel, then easily ran a power wire to the pump under the carpet beside the drivers seat and through the engine access panel. The Airtex pumps use very little amperage, so you should have no issues with circuit capacity.

DWR46, Perfect, thanks!

Panteradoug, certainly understand nurturing, sensitivity and potential. Very nice!

Maybe a button instead of a switch? Should only need to run the pump for a few moments. Avoid the chance of forgetting to shut it off?

Larry, good idea, button switch would certainly prevent leaving the toggle switch on. Was thinking if I had a vapor lock (VL) situation again the toggle might be good. I had VL happen several summers ago and was not good. I put some heat shielding on the fuel lines and hasn't happened again, but if it did leaving the fuel pump on until the engine ran/cooled might be a good option. It's a flow-thru electric pump so can leave on or off depending on what I want.

Thanks for your good recommendation.. Ron

@ronwitt posted:

DWR46, Perfect, thanks!

Panteradoug, certainly understand nurturing, sensitivity and potential. Very nice!

Part of the "cat's" survival for this long.

@ronwitt posted:

Hi All, Happy New Year! I have a stock Pre-L 72 Pantera with Motorcraft 4300D D2ZF-AA carb. If I dont start the car every week the carb fuel bowl seems to evaporate and needs a lot of cranking to start the engine. If I start one day and turn around and start again the next day it fires right up. I'm thinking about adding an Electric fuel pump to just fill the carb bowl with a separate on/off switch. I will only use to prime the carb then turn off so need a flow-thru pump and probably 5.5psi rate? Has anyone done this for recommendations on type of pump, location of mounting pump and switch? Thanks for advice, not interested in switching to different carb/manifold or EFI. Thanks and Happy New Year! Ron

Hi Ron, before you invest in an electric pump and all manor of other bits and pieces, you might want to try my trick. I have a pretty stock 351C with mechanical pump and carb with electric choke. When the car has sat for a while, e.g. one or more months. I get in the car, don't touch the accelerator, and I crank the car for around 10-15 seconds, during this time, I see the oil pressure come up, which is a nice benefit when cold starting an engine. I stop cranking and pump the accelerator about 9-10 times to cock the choke and put some fuel into the intake, then I crank again and it starts immediately.

Cheers, Tim.

Hi Tim, thanks for your comments. I've been going through close to the same cold start process as you but concerned about the strain on starter and battery drain. I don't have an electric choke, but know it's set correctly. I figure for less than $50 I can install an electric pump for prime only and not have to worry about overworking other components for a smooth quick cold start. The pump arrives on Monday so will start next week and document the process to share with those interested. Thanks again and Happy New Year! Ron

Installing an electric pump to prime the carb does reduce the stress on the entire system of starting a dry engine and it does no harm.

Hi Ron, no worries, it sounds like a good solution,

cheers, Tim.

Hi Tim, always great to hear the opinions, advice, and experiences of other Pantera owners/lovers. Happy New Year!

Hi Ron. I did this exact mod, for the same reason a decade or so ago. I used a late '80s stock Ford TBI electric fuel pump permanently attached to the fuel sender inside the fuel tank. The TBI pump puts out 10-12 psi and can be easily regulated down to 5-7 psi for carbs. An EFI pump runs at 48-55 psi and will overheat and quit if you try to regulate it down that much.

Fuel pumps are not marked and look identical, so with used parts- unless you physically pull them off a wreck, you cannot tell them apart. Running a pump inside an uncut Pantera fuel tank is far quieter and handier than running a usually noisy external pump where the power wire can be knocked off, stopping the engine.

There's a POCA Newsletter article in the POCA Archives detailing the mod. I use both a mechanical pump and the TBI pump with a reverse flow valve between the two to my Holley. Still works fine & the e-pump can substitute for a failing mechanical pump on the road. .

Hi Bosswrench, Happy New Year! Thanks for sharing your insight and experience with your electric fuel pump.

You are certainly right about fuel pumps not being marked and look alike. I received my Airtex pump yesterday, part# not market on the box or pump, fittings looked rusted and bag with misc. items opened. Part number on box didn't match to anything I could find on the internet with several labels placed over weird numbers. I sent back and reordered from Amazon. Not going to install just a random look alike pump...crazy.

Thanks again, Ron

...You can see where I mounted the E. Fuel Pump, high on the Chassis. NO hoses near the Header!

1. The Mechanical Fuel Pump was Gone on the First Day! I don't trust them, I have had a few go-out on me...at the worst of times. Never had an Electric Fail. but I do Travel with a Spare E. Pump. also, the Mechanical pump, being mounted next to the Header IS the Cause of any Vapor-Lock! The Electric Does NOT Have to be mounted LOW!! Take it from Experience...You want this pump as FAR from any Heat Source, as You Can Possibly Get IT.

2. It is a Holley 'LOW" Pressure pump producing 4-5 PSI Max.

3. It is mounted to a Jacobs pressure regulator and the pressure is Calibrated at a Steady 4.0 PSI, working Engine Running.

4. The Regulator was NOT Needed, but I used it for the feature of Detouring Fuel back to the tank, once set pressure is reached, relieving the stress on the pump. Any 'Heating' of the Fuel, has not been noticed.

5. Holley E. Pumps are VERY Noisy. Where this is mounted, I could hear it 'Barely', over the Engine Sounds. The In-Cockpit Gopro Camera, caught it on Audio. When I played the Video back it struck My Nervous System Badly, as I realized, I had Listened to the Vibration, constantly, during a Desert Trip, for well over 1400 Miles. As soon as I was back in the Garage, I immediately added Two Rubber 'Vibration/Noise Isolators', (the Isolators with Dual Threaded STUDS 1-1/2" OD 1" Thick studs are 3/8" NC), between the Pump and Chassis. ALL is Very Good, Now.

6. The switch is mounted on a Gauge Plate to the right of the center console, with a RED Protection anti-accidental ON) Flip-Cover. Before starting the Engine. I fill the float bowls, shut the pump off, so the needle seats aren't 'stressed' (especially when the Engine is Already HOT, to prevent Flooding), No need to prime when it's already Hot. For start-up, I hit the accelerator 4 times (Only when COLD) and it fires right-up. Then the pump is turned back on. When temp starts to come up, I turn on the Main Rad Fan, Aux Fans are use when needed. The Aux Fans are OFF when cruising on the Freeway, as the coolant runs cooler. The Aux's actually 'Block' the air flow, when at 75-80 MPH, proven in Testing.

MJ   

Those in-tank factory pumps (either TBI or EFI) are deceiving. Not only do they not carry a stamped or decal part number, the roller-impeller pump itself is only the size of a silver dollar. The rest of the assembly is the high rpm drive motor and the fuel return mechanism (if it has one). There's a fine shear-wire final connection to the motor, so if you routinely run the tank dry on payday, after 2 or 3 times the lack of gas to cool the submerged pump can overheat the motor and burn the fine wire in two.

We found this out the hard way with Judy's EFI-powered '97 Z-28 which uses the same appearing pump as the one I used, from a TBI-powered Ford Bronco. As an aside, to change pumps in a GM Z-28, the whole live rear axle & rear brake assembly must be removed, then the fuel tank to access the submerged pump- all for want of a simple 50 cent access door in the trunk. Besides the complication, the shear wire is an undocumented "feature." Not only is it theoretically dangerous to burn it out inside a tank, it is not easily repairable. I've not found a source of correct shear-wire. Luckily, the Z-28 was fixed under warranty. Unluckily, a month later the ring & pinion went out, so out came the rear end again. Second new GM I owned and the second diff I lost. GM just doesn't know how to set up a limited slip differential.

So while you could rewire a blown fuel pump with heavier gauge wire or hot-wire a new pump to check its pressure output with a bucket of water and a gauge, you can't submerge the ungrounded pump in a conducting fluid like water. I guess after thinking about it, you could use safer diesel for a submerged check. Buto don't try check-running any such pump dry for more than a few seconds even if you temporarily plumb the pump with plastic hose. Wrecking yard roll-over fuel pumps can be blown this way too, because apparently many drivers of roll-over crashes keep their foot buried while the noisy/sky/ground thing is going on.

I can hear all electric fuel pumps when they come on. Including the in tank. In fact, turning the ignition switch to run without starting the engine is one of the tests on EFI cars to confirm the pump isn't bad.

Anyone who isn't hard of hearing clearly can hear it click on momentarily at that point.

In my case with my Pantera, there is little way to hear a chassis mounted electric pump. Installing a manual on/off switch for it, presuming that you retain a functioning mechanical pump would be the best option as well as mounting the pump on rubber blocks.

Considering the fuel pump repairs that I have done, it is more common to have the pump eccentric come loose internally or in fact the wrong pump installed to begin with then to have the actual pump fail.

New mechanical pumps are in stock in your local Pep Boys so I can't argue that there aren't problems with them.

In recent interviews with surviving factory drivers, when asked about the SW pumps installed in the factory racing Cobras, the drivers said, one the car was running, they switched them off.

Now if you have never heard the old SW pumps run, that thing actually vibrates the chassis where it is mounted. It's as loud as a mini-cement mixer and to have to turn it off in a race car running open exhaust headers makes quite a statement.

One of the first things that I did to my Pantera was to install 2" thick foam insulation under stainless steel fitted sheets on the firewall. That helps tremendously.

As MJ states, you don't NEED to mount it low. It's such a short rise up, none of the pumps I've run have ever had issues with running dry but considering how far away the mechanical pump is from the exhaust in my car (180° headers up and back) the vapor lock issue is more of where the fuel lines themselves are.

You should note though that 1/4" thick Delrin insulating gaskets are available for the mechanical pumps.

With any of the carbs available, you don't need to run more pressure then the mechanical pumps make to begin with and considering the failure rate that I have seen with the Viton carb inlet needle and seat, it's risky to run much more then about 5psi.

Having a car sit for only a week and have the carb be dry sounds more like a leakage problem. I know with a Holley carb if the power valve begins to leak it will eventually drain the bowl where the valve is. If you are going to install an electriced powered booster fuel pump, then just be sure that you get one for a carb and not EFI. An inline pressure regulator might be a good idea to keep the fuel pressure on or about 5 psi.

Absolutely agree with Doug on the incredible e-pump noise. I had a Holley Super-pump on my do-everything Corvair and after 2 weeks of changing its mount spot, I took it off. That car had a totally tuned exhaust clear back to the exhaust valves & lots of tire noise. Had Holley's rubber-grommet-insulated mount. Didn't help at all, so don't waste your money if its not going on a full race car. That experience is why I went to an in-tank pump on the Pantera. I can hear the Ford pump come on but not when the engine is running.

@bosswrench posted:

Absolutely agree with Doug on the incredible e-pump noise. I had a Holley Super-pump on my do-everything Corvair and after 2 weeks of changing its mount spot, I took it off. That car had a totally tuned exhaust clear back to the exhaust valves & lots of tire noise. Had Holley's rubber-grommet-insulated mount. Didn't help at all, so don't waste your money if its not going on a full race car. That experience is why I went to an in-tank pump on the Pantera. I can hear the Ford pump come on but not when the engine is running.

CORVAIR? E'tu Brutis?

Yes- I bought the thing new as a family sedan in '65 (wife & 2 kids at the time), drove it 275,000 miles and only(?) used one spare body-shell, 4 engines (five cranks), plus three transaxles. Commuter, touring car on Club runs & vacations, autocrosser etc. To say I beat upon it is understating the facts. When I sold it in 2000 (for more than I paid new), it had 4-wheel Z-28 disc brakes, 15x 7" & 15 x 8" wheels, two Weber 3-bbl carbs and about 200 bhp. Luckily, too old for CA SMOG laws. Literally nothing was stock except the door handles.  I still miss it.

A momentary start switch. Push the rubber covered button to energize and it springs back to the off position when it's released. About $8 on Amazon.

Mike Mileski

Tucson, AZ

Mike, seems like another good push button option. I decided to go with a small black toggle switch. Mounted it under the dash left of the steering column by the trip odometer reset. Decided if I ever want leave the pump on because of maybe vapor lock it would be better to have the toggle instead of using one of my hands to hold in a button for a period of time.
Thanks, Ron

Carter also makes electric pumps for carbs that don't require a regulator. My car is away right now, but will look to see what model number if I still have the box. Not silent, but not overly noisy setup in line.

Thanks Otis, I already bought an Airtex pump but others might be interested in your Carter # when you get your car back to check. 99% of the time I will only use my pump to prime carb when needed so noise of pump not a concern. Understand if someone runs the pump all the time noisy pump might be an issue.

Thanks, Ron