Ok, I posted a thread about this problem a while back and took yall's advice and installed a needle valve to dampen the noise on my fp gauge. It worked great for a week or two then the noise came back. And when I mean back, it came back sounding like a MAD rattlesnake and the needle would shake like helk too. The needle would fluctuate (at cruise) by as much as 5 psi!! Any time I ride in my truck, I have to have the windows down and stereo up to keep from hearing that darn noise.

I've noticed that if I disconnect the hose to the needle valve, and reconnect it, that the noise goes away for a day or so, then comes right back to normal. What can I do about this? This noise is driving me crazy!!!

Is it possibly a faulty gauge? Should I relocate my fp hose to another location (currently hooked up to the needle valve which is hooked up to a tapped banjo bolt)? I just want to be able to drive down the road and not get road-rage from that freaking gauge!!!

Thanks for any help,
Hunter

 

Is the needle valve closed almost all the way?

On mine, I close it off completely, then start the truck and crack it open just until I get a good reading that will rise and fall rapidly with the pressure variance.
I had to reset mine once in 3 years.

Ed

 

Ed's advice is right on. The reason the noise stops when you disconnect the line is because air gets in the line and dampens the pulsations. I run my needle valves open less than an eighth turn from full off. Tighten the nut under the needle valve handle after you adjust it to keep the setting from changing.

 

I've tried every adjustment on the valve that I could think of. A hair open, less than an 8th, an 8th, barely more than an 8th, and so on. I can't seem to win this on going battle.

 

No one else does it this way and now I don't need to but what worked for me for a long time is to trap the air in the line. I looped the line over and around the master cylinder a couple of times and that way the air could not get out completely, cured th eproblem. Disconnect the line at both ends, blow it out to get the fuel out of it. Get a loop or two in it to keep the air in the line and hook it back up. Ran mine that was for a long time.

 

TST suggests using an inline fuel filter to trap air. My experience is that no matter what you do the fuel will eventually displace the air.

 

I do the same as Haulin' Loop it over the master cylinder. It's actually zip tied to the oil dipstick tube on the intake air horn. Been almost 2 years now with no problem.

 

I just got a fuel psi gauge for my 12v, I piped into the fuel pump banjo and got a needle valve to install off the banjo.I'm going to use air brake line for the piping, but I must say I have picked up some good pointer's from this post on the piping!

 

Let's move the line to the outlet of the fuel filter. It's a little farther away from the VP pump so the pulsations might not be as bad. You've seen where mine hooks in at on the line and I don't have the noise at all.

 

Ya, sounds like a good idea to me.

 

I used 1/16" Stainless Steel tubing after my needle valve to the guage. No pulsations at all with the valve 100% open...only bad thing is that the tubing and fittings are pretty steep in price...unless you have a friend in the instrumentation field.

 

http://www.differentialpressure.com/psnub.htm


Mod edit to repair link

 

Only problem with snubbers is the smallest size you can find is 1/4'', most folks need 1/8''. Nothing a couple bushings won't fix but it starts getting heavy and has two more potential leak sources.

 

I had the same thing with our 24v..I used the needle valve to dampen the pulsation of the pump. Well I am not sure that its the VP44 supplying the pulsations. The reason that I say this is because when I installed my FASS system..the problem went away. I did not change anything as far as where the fp gauge is connected..so if there is pulsations coming from the 44 it should still be there but its not. It think what we are seeing is pulsations from the lift pump!
On the FASS system I do have 12' of rubber 3/8" line that would dampen all the pulsation that a pump would give so maybe it was not the 44.
On the fuel system doesnt the fuel move in one direction??? As it is pumped to the 44 it continues to move in one direction on thru the pump and then the unused fuel is returned to the tank??
Anyway just a thought of why our fp gauge is as quiet as a church mouse

Rick

 

I have no gauge noise, and I run braided line directly off my max-flow adapter at the VP! I guarantee that the braided SS doesn't dampen the vibes. If I DID have a problem, I would insert a length of grease gun hose to help dampen. Before I did the max-flow, I had GG to my braided, now I run the braided direct-- still no noise, except if the gauge comes loose in its cup.

A lot of this has to do with guage quality, IMHO. I have a Hewitt 30psi mech FP gauge from Enterprise Engine, and I couldn't be happier with it- no isolator, no leaks.

Justin