Stock 73 fuel pump?

Hey all I been tinkering with this 1406 edlebrock carb for awhile now and have come to the conclusion that It may be receiving to much fuel from the stock pump. Does anyone know what a stock pump on a 73 gt might be putting out pressure wise?

I did order a fuel pressure regulator and a gauge as well a fuel filter. I’m thinking that the edlebrock is getting more fuel than what it wants, 5-6 from what I can gather.

Any help would be greatly appreciated.

It’s a stock 400, with a 1” insulator and a 1406 edlebrock.

 

Any Ford carb should be around 3-5, wavering, at idle, and 6 above 2000 RPM. If it's overfueling, I'd look at two things: the needle and seats, or an internal leak. The Carter Thermoquad is similar in design, and had a bad propensity to leak from the primary wells at the bottom of the phenolic body; it's entirely possible yours could be doing the same, but in a different way. I do remember that Quadrajets can also leak from the primary wells, if it is fairly old.

 

I had a similar setup on my 400, and later on my 302. Should measure about 4.5 - 5.0 psi. I made a T connector from some plastic vent parts to get a port so I could measure it with the engine running.

I have that same 1406 here -- I retired it because of a recurring plug-up of the idle circuits that I was never able to get cleaned with various carb soakers. So that might explain your idle problems.

 

The air filter is a bit dirty so maybe I got a clog. I’m Gunna pull the carb and clean it when I hook up the pressure gauge so maybe that will help do the trick too.

 

IIRC, the 1406 has an auto choke. Is that set up correctly?

Joseph

 

I just watched a video on how to reset that so I’ll give that a try too. The plugs keep fauling and there is gas sometimes on the valley of the intake manifold. So i think that it might be getting to much gas even at idle.

 

It's sounding like a leak somewhere. A faulty choke won't cause puddling outside, so you should pull the top, inspect the needle & seat, and verify they properly close. Just invert the airhorn so the float seats the needle, then blow breath through the fuel inlet. No air should pass through. And the top of the float should be fairly parallel with the gasket surface of the airhorn.

 

Well it turns out that with the fuel pressure gauge hooked up to the fuel line on the carb I’m getting a steady 3 psi of fuel. That sounds like that’s low compared to what I have heard these like to run...

How would I go about adding more fuel pressure? Inline fuel pump?

 

Also I just turned the car off and back on, and it’s reading zero on the gauge now. Car idles fine and revs good. .....

 

If 3 was the reading at idle, that's spec; 3 at 2000 RPM is way low, and in combo with the engine overfueling and the puddling fuel, I'd say the needle and seat aren't working and you have a float bowl leakout.

 

With a new needle and seat, that will allow the fuel line to properly pressurize.

 

I think you are on to something here.

 

Bumping this thread, I finally got back around to mess with around. Took awhile to fire up but it was idling just fine. My fuel psi gauge read 4 pounds. Took her for a spin. Got to my first stop light and the thing dies. Doesn’t want to idle. So I had to left foot brake gas type deal home. Popped the hood and now the gauge is reading zero but still idling and revs just fine. My buddy has suggested replacing the fuel filter. Perhaps it’s clogged?

 

They get replaced every 5000 miles, unless you or someone else plumbed in an aftermarket (i.e. bigger filter), then it's every 10K miles. So, yeah, pop a new one in. They're inexpensive.

 

Just a thought here, I see by your signature the you are in Denver since you are so high ( not the smoke kind) is it possible to rejet that to lean it out a little?
Maybe some of the others can offer some better advice
I know that is not all the answer to you issue

 

I would think that 4PSI is pretty low. I ended up taking the in-line filters off of my truck (352FE with a mechanical fuel pump), and just rely on the filter in the pump itself. I had read that the mechanical pumps don't like to "pull" fuel through a filter. They do better if they can "push" fuel through instead. Don't know if that's true, though.

As 62restomod said, hopefully better advice is on its way.

Joseph

 

It's not that pumps 'do or do not' like something, it's the fact that gasoline vaporizes, and putting it under vacuum, especially in the vicinity of heat, speeds up the vaporizing. Then the vapor reaches the carb, and causes all sorts of hate and discontent.

 

I’ll take the fuel pump off and see if there is some sludge stuck in there or maybe it’s not working well anymore it doesn’t look to old but who know , whatever is going on is happening before the carb because the gauge is on that 90 degree fuel line attached to the carb. .

 

Turns out that I don’t have a filter... I looked and double checked all the fuel lines and I can’t find one anywhere in the system...

 

I know it's overkill but I like two filters. One between the frame and fuel pump then another between the pump and carb.