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Mon Apr 09, 2012 1:08 pm

I have a holley fuel pressure regulator. I am needing the pressure at no more than 3 psi (due to the Weber ICT's)
Cold I can set the pressure to 3 psi and after it warms up a few minutes the pressure on the dial goes to near 0 psi.
Do I set the PSI cold and then run with it or do I have bigger problems with the regulator. I have a new fuel pump.

Mon Apr 09, 2012 5:34 pm

Bypass regulator at run for a while.... You may find the required FPR is a joke....

People insisted there would be a problem with my Weber IDFs with Carter Electric 4 psi pump.... So far not a problem....

Dale

Mon Apr 09, 2012 7:32 pm

you can run 8psi with webers IF YOU KNOW HOW TO DO IT.

Which "regulator" are you using?

Tue Apr 10, 2012 7:50 am

I am running the 12-804 Holley regulator. I have been told to keep the pressure at 3 psi or under. My carbs are little 34ict's. After setting the floats with Mark Harney's help and getting the fuel pressure down the carbs really ran well.
I

Tue Apr 10, 2012 8:43 am

Quote: you can run 8psi with webers IF YOU KNOW HOW TO DO IT.

Since everyone says to run 3psi for pressure, why would you want to run 8psi (unless it is an emergency situation) and what is necessary to do it

Tue Apr 10, 2012 8:52 am

to get more volume for higher power capability. It's too complicated and I don't have the time to go into why/how right now.

Tue Apr 10, 2012 9:26 am

Saucerman ...... I had what sounds like exactly the same problem. Fuel pressure starts out fine then drops to near zero. I assume you are running a mechanical fuel pump.

For me, the problem was a bad pump ...... two of them to be exact. They were both NEW Brosol pumps. I really don't know what was wrong with them since I didn't bother to cut them open, but I was able to confirm with testing that the pumps were in fact the problem. Replaced the Brosol's with a Bocar ..... problem solved. BTW, after evaluating the Bocar I determined a regulator was not needed. One less thing to fail.

Good luck.

Tue Apr 10, 2012 10:26 am

You know, I had not thought of the "new" pump being bad also. I ordered a spare also so maybe I will try it out tonight and see if that makes a difference.

Tue Apr 10, 2012 11:29 am

I ran the same 12-804 and liquid filled gauge and had the same problem as you and hundreds of other guys (including the V8 crowd) tried the famous BS fix by removing rubber plug in back to reset pressure. I dont know which was bad but both went in the trash faster then I could blink, now I run Carter w/3 psi pump straight to IDA's of course through couple filters. 12-804 is a POS even if it has Holley written all over it, I think my buddy took it from the trash when I wasnt looking.

Tue Apr 10, 2012 11:45 am

Carter huh? Is that the type of regulator that has the glass bowl in the middle? I think I have seen them in Midway USA or something.

Tue Apr 10, 2012 11:49 am

Midway USA? What was I thinking? That is guns, not VW's. Midamerica Motorworks I mean.
http://www.mamotorworkstv.com/vw/product/vintage-s...ly_319758/

Is this a Carter?

Tue Apr 10, 2012 11:55 am

Sorry Carter rotary fuel pump, no regulator no gauge. Temporarily used another gauge only to see pump was putting out descent pressure. Ignore my ranting just felt like I got duped with crappy product and seen others return exchange.

Tue Apr 10, 2012 12:51 pm

No, that's cool. Thanks for the info.

Tue Apr 10, 2012 1:51 pm

These directions came with my Aeromotive Regulator:
Most standard carburetor regulators, including Aeromotive’, require some flow through the unit while pressure is being adjusted. the proper method is to set pressure with the pump on and the engine running. Correct procedure for a new regulator installation includes: 1) Turn the adjustment screw counter clockwise to the lowest pressure setting. 2.) Power and run the pump, with the engine off, until the bowls are full. 3.) Turn the pump off. 4.) Start the engine. 5.) Turn the pump back on. 6.) Adjust base fuel pressure up to the desired set-point by turning the set screw clockwise and locking the jam nut.

My regulator doesn’t seem to keep consistent pressure, every time I look at the gauge it reads something different, what is going on?
Chances are good you have a liquid filled fuel pressure gauge. This type of gauge will change it’s reading as the temperature of the gauge case changes. Because it’s sealed to contain the liquid inside, a liquid filled gauge no longer compares fuel line pressure to actual atmospheric pressure, reporting the difference. Instead, it compares fuel line pressure to the pressure inside the gauge case. Unfortunately, as the liquid in the case heats or cools, it expands and contracts, causing case pressure to change as much as 7 psi plus or minus. As a result, gauge readings can fluctuate from 8 psi cold to as little as 1 psi hot! Note: Fuel line pressure is NOT actually changing, just the pressure in the gauge case. To confirm if this is occurring, procure a heat gun or blow dryer and heat the gauge from cold to warm and then hot, while running the fuel pump. Observe if the pressure reading drops, if so, you found the problem

Tue Apr 10, 2012 6:32 pm

There is no switching the pump on and off. Mechanical pump. The pump produced too much pressure for the 34 ICT's so I put in a regulator.