After our trucks sit for a couple of days, especially in this heat, they get hard to start. So I put in an electric fuel pump. That helped considerably, but after a month or so, I've noticed that it's sometimes hard to start, due to too much fuel. Yes, Virginia, you can flood a 460! So I decided I needed a pressure regulator...

I ordered the Summit regulator, and enough hardware to actually install the darn thing. Hardest part was picking out a spot for the regulator, but I settled on the inner fender, drivers side, ahead of the window washer solvent reservoir - pretty much in-line with the former mechanical pump. Used my handy punch to make two dents, then drilled a couple holes...

Assembled the components to the regulator. A barb fitting for the inlet, an elbow for the outlet, and a plug for the other outlet. Mounted the regulator in the bracket, then mounted the bracket to the fender...





I thought I had done a fine job, until I reviewed the photos. The hose feeding the regulator was rubbing against the pressure line for the power steering...





So I trimmed the excess from the hose, and now it has a nice smooth and unobstructed curve to the fuel filter...





I used a right angle 3/8" npt to 3/8" barb to send the fuel back to the carburetor without introducing another bend to the hose. This way, the hose lays flat (well, in the same plane) as the rest of the assembly






The regulator has two outlets, so I plugged the second with a nice anodized aluminum plug from Summit. I bought the package of four so I could use the others in the intake manifold or thermostat housing. Or in another regulator for another truck...




The entire assembly looks pretty good, I think


And the pressure at the carb looks good too.





And in limited testing, the truck starts easier. But wait a month and ask again...

 

Keep us updated on how it does. My truck gets hard to start when its warm and I need to start it in hot weather. I was considering running an electric fuel pump/ regulator like you're doing. Did you just buy a block-off plate for the mechanical fuel pump location?

 

Yes, I pulled the mechanical, and replaced with a block-off plate from Summit. The plain chrome for the 460 was relatively cheap. The bolts from Lowe's may have cost more.

The pump is pretty quiet. I like it because I can tell by the change in tone when it's "pumped-up" and ready-to-go.

 

Good job. Since you are using an electric fuel pump, don't forget to put a cut-off switch for safety reasons.

 

How is it holding up? Was this a worthwhile upgrade? Thanks! -Greg

 

Thanks for asking. The electric fuel pump and regulator was the best thing I’ve done for the trucks.

It’s been really hot this summer (today was 122) and the trucks are starting and running great. No problem at all with the regulators, although I have changed a couple of the pumps.

i drive the 79 the most, and I don’t think I’ve replaced the electric pump in that truck. I drive the 77 and 78 less, and I’ve had to replace those. Same model pump across the trucks, so lack of use is apparently hard on them

 

I have the same regulator, not yet installed. I was thinking of using the second outlet for the pressure gauge.

 

I understand the most elec pumps are more suited to be a pusher than a puller and should be back by the fuel tank.

I also understand. " Ford 351M and 400 fuel pumps put out about 7 psi if "spot on". Holley and Motorcraft Carbs can take in excess of 7 psi due to longer float arms with large floats. Carter AFB & AVS & Edelbrock carbs have shorter float arms which is in part why they are more compact, and smaller floats and they are less tolerant of higher fuel pressures, 6 psi is the max that Edelbrock recommends for their carbs which are copies of the Carter carbs. They recommend that a max pressure used at 5.5 psi. High fuel pressure does not mean more power as many cars we considered as muscle cars used 4-6 psi. You likely need a decent Fuel Pressure Regulator like Holley's # 12-803 and use a fuel pressure tester in a tee between the carb and FPR to set pressure at 5.5 max. Do not waste money on a Spectre or Mr Gasket FPR. Once set you can remove the tee and tester."

I would move the elec pump back by the tank (to prevent the chance of burning it up) and turn the pressure down.

Electric Fuel Pump: How to Do It Right

https://www.hotrod.com/articles/safe...l-pump-wiring/

https://m.roadkillcustoms.com/wire-electric-fuel-pump/

 

Great to hear. I'm working on a 78 I6 and am learning about tuning. achieving and maintaining onsistent inputs are the things I hear a lot. Holly makes two fuel pressure regulators one for 1-4psi and a 4.5-9. Which one do you run and why? Thanks again!

 

That big blurb was not mine personally, just some saved advice. I have a Mr Gasket one (came on the Bronco) and it works great.

 

Fuel delivery in a carbureted system is different than many might think, there has to be an adequate amount of both pressure and volume. Excessively high pressure is not a substitute for inadequate volume. The fuel pump doesn't produce any pressure, it produces a flow. The restrictions are what produces pressure.

Why is this important? It's because the entire carburetor is designed and calibrated around a very specific fuel level in the bowl exerting a column height pressure on the air bleeds and orifices (also located at a specific height) "pulling" fuel from the well, this needs to be maintained at all times under all conditions.

While the inlet needle, seat, and float arrangement is sometimes compared to a toilet bowl that isn't how it works. Whether at idle or wide open throttle when fuel demands are greatest, the fuel height in the bowl ideally is supposed to stay at the specification height +/- 1/32" on a constant basis (unlike a toilet bowl) and that tiny viton tipped needle is required to start and stop the flow a gazillion times a minute.

The float itself has a certain range of adjustment height to allow for a range of pressures but, if the pump output pressure is too high, or too low, then the average fuel level height will likely be out of spec under certain operating conditions and/or vary widely. This interferes with the carb calibration and AFR jetting, possible lean conditions, or flooding.

Give the carburetor what it wants and it will give you what you want. The Holley system of fuel height adjustment "on the fly" is probably the most convenient method ever designed. A 5/8" box wrench iirc and a flat blade screwdriver is all it takes. Done.

 

Most carburetors are going to want anywhere between 5 and 6 pounds of pressure or slightly more maybe, with an Edelbrock carb wanting no more than 5 lbs.
Too much pressure will blow the needle valve open and deliver too much fuel into the carb, and too little pressure will starve the carb of fuel.

 

The 1979 Ford truck shop manual shows the specifications for the mechanical pump on the 460 engine in the F series as 5.0-7.0 P.S.I. static pressure with a minimum flow volume of 1 pint in 20 seconds.

 

Notice the volume spec - if my arithmetic is correct it pencils out to a minimum flow rate requirement of over 22 gallons per hour.

Obviously that far exceeds what the engine could ever need; at 60 mph it should only burn a couple few gallons - but the pump itself must be capable of flowing that much to be considered adequate.