Fuel pressure regulator??????

I got a problem, I put a weber carb on my 256 awhile back and have noticed that it has been running rich. After many hours of adjusting and tweaking the carb I called Weber and they said that I need to knock down my fuel pressure. The mechanical fuel pump puts out aprox 5-6 psi and the carb needs

2.5-3psi. All the parts stores that I have talked to say that there is nothing I can use to drop the pressure. I would think that there has to be some sort of regulator that will output a fixed or adjustable pressure that I can put in the fuel line after the pump. If anyone knows of a part # or manufacture that I can get something to fix this I would be forever in your debt. Thanks

Scott

90YJ
Reply to
Foot Loose
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For what it's worth ... the fuel pressure sounds ok to me (my V6 boat engine spec is 3-7 psi). You need that pressure to supply sufficient fuel at running speed. Might I suggest the carb may have been modified either for a larger engine or by someone to run rich(er) ... meaning the primary jets/metering rods (I'm a 4 bbl guy, excuse my ignorance here) may be "oversize".

Reply to
bowgus

Also, if fuel is actually "leaking" past the float/needle valve and "dripping" into the carb, check that out. It's the job of that assembly to enable/disable fuel flow keeping the fuel bowl topped up. So you can see where I'm going with this ... my thinking, the problem can in no way be caused by 5-6 psi fuel pressure.

Reply to
bowgus

Reply to
L.W.(ßill)

Well bud, I have been a wrench for many years and everyone looks the obvious first, check the float level and make sure it is set properly and that there is nothing obstructing the float needle. If all is ok rejet the carb on both the idle and high speed jet. Get the two next smaller jets for each try the next smallest first. Put a fresh set of plugs in drive it for about

50 miles, pull the #1 plug and look at it. If it is light tan to a dull whitish color you are right on, if it is black you should install the second of smaller jet. If equipped with an idle mixture screw turn it in till it seats (gently) and then turn it out 21/2 turns, tweak as required.
Reply to
HarryS

You need a regulator for your system. These are readily available from many places. Weber carbs "like" lower fuel pressure than most carbs (2-4 PSI). Here is some info on recommended pressure for the Weber carbs:

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Here is a regulator you can use:

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Chris

Reply to
c

That is what the guys at weber said that I need to lower the pressure. Thanks for the link Chris I'm gona give it a try.

Scott

90YJ

Reply to
Foot Loose

I had this same problem. I fiddled around with everything in the carberator and tried the pressure regulator. The pressure regulator could not be turned down to a low enough pressure without starving the carberator for fuel. I bought an electric fuel pump rated for the correct low pressure and it has run like a dream for two years. I was able to lower the float to keep off camber flooding to a minimum. Another trick if your replace a one barrel with the Weber is to turn the carb. 90 degrees which puts the bowl stick out toward the drivers side. The thing will not flood out even when the wheels start coming up (I don't like to talk about how I know that). I bought a Purolator universal replacement pump at Advanced with the right pressure rating.

Reply to
cj573cj5

There are different regulators for different ranges of fuel pressure. The one I recommended is rated for 1-4 PSI, which will not restrict the fuel flow like the higher pressure regulators will. Most regulators are rated to go down to about 4 PSI, and trying to get them to run at 2 PSI or so will cause a fuel starvation problem.

Chris

Reply to
c

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