Pressure regulator

sturgis 39

sturgis 39

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I have two 81 carburetors feed by an electric fuel pump. The recommended fuel pressure is 1-1/2 to 2-1/2 psig. The pressure regulator that is now in the system is a chrome Speedway regulator that is adjustable with a dial on the top. The catalog number for the regulator is 560-58500. The pressure gauge is catalog number is 910-11852. The pressure jumps up and down. The electrical system is six volts. I would like to try a different pressure regulator. Could somebody recommend a regulator?

I thought i posted this on the V-8 site earlier but is on the Model A site.
 
the fuel pressure regulator i picked up at Kragens works, i needed to turn it down to the half mark to get the 2 1/2 pressure so the dial reads 2, but again it is at 2 1/2 instead of the 7 1/2 with out it, but it is steady. it is Mr.Gasket, though they all look the same.
rich
 
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If the pressure jumps up and down running that is normal. When the fuel is used in the bowl the float drops and the needle valve opens. When the needle valve is open the only back pressure on the pump is the small metering hole going into the needle valve. As the float rises the needle closes and the pressure rises. A ball type needle valve opens easier and in rapid motions and the pressure just slightly giggles keeping the fuel in the bowl almost level all the time. If the fuel to the carb is completely shut off it should have a high fairly steady reading. Also a meter needs a small hole in the threaded stem called a damper, with out a damper the needle will jump as you describe. I ran a 10-32 tap in the meter I am using, drilled a 1/16" hole in a brass 10-32 screw, put a screw driver slot in it and screwed that in the stem. This smoothed out my meter. G.M.
 
Holley makes a low pressure regulator (PN #510-12-804) which is preset at 2.7 P.S.I. and is adjustable from 1 to 4 P.S.I. It is chrome plated and sells at Jegs for $27.99. They also have a rebuild kit for this regulator. There website is: www.jegs.com Regards, Pat
 
4D Tom the pump pressure is pulsating due to the needle valve opening and closing. A needle valve will usually have larger voltage swings from 1-1/2 to 3-1/2 lbs. With a ball type valve the balls will sit there and just jiggle from 2-7/8 to 3-1/8 lbs. Most gauges are not made for rapid changes in pressure and will jump around. Some gauges have built in dampers which is a very small that traps some fluid and cushions pulsations. If you look in WW Grainger catalog in the area of gauges you will find a damper. This is like an 1/8" to 1/4" pipe adaptor with a very small hole in it. G.M.
 
G.M. said:
4D Tom the pump pressure is pulsating due to the needle valve opening and closing. A needle valve will usually have larger voltage swings from 1-1/2 to 3-1/2 lbs. With a ball type valve the balls will sit there and just jiggle from 2-7/8 to 3-1/8 lbs. Most gauges are not made for rapid changes in pressure and will jump around. Some gauges have built in dampers which is a very small that traps some fluid and cushions pulsations. If you look in WW Grainger catalog in the area of gauges you will find a damper. This is like an 1/8" to 1/4" pipe adaptor with a very small hole in it. G.M.
Click to expand...

GM,
Can 'ball valves' be purchased for 81s and where?
Where does the damper fit in system..i.e.-after regulator/where? lol , Rick
 
I use the Mallory regulator and a dampened pressure guage. Mine appears to hold steady and have used this set up for 6 years.
 
Uncle Max

I do not understand your post about the pressure regulator. Could you expand your response so I know what you are talking about.

Thanks
 
sturgis 39 said:
Uncle Max

I do not understand your post about the pressure regulator. Could you expand your response so I know what you are talking about.

Thanks
Click to expand...
... I was responding to the post directly above, where Hardtimes was asking where to get "ball valves".
 
Hardtimes The damper is not used in the normal operation of the engine this in the hole that is in the pipe threaded part of the gauge or like the one I described from Grainer which is and adaptor the gauge screws in. The Stromberg carb has a built in "damper" in the needle or ball valve body that is about .086 which keeps to much fuel from flowing into the bowl and overflowing. They tried different sizes of holes according to the service manuals and settled on this size. This is what makes me laugh when I see people with dual carbs and think they need 3/8" fuel hose then it's reduced down through 2- .086 holes. Uncle Max has the ball valves, rebuilds the Strombergs and also sells the new Strombergs and he's a good guy to deal with and knows what he is doing. G.M.
 
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