I finally got rid of my junk isolator.

I ran 1/4" air brake line. I used a needle valve at the pump, followed by a snubber. Before when my gauge was working right with the isolator, as soon as I hit the key, the FASS would slam the gauge to 21psi. Now with the new set up, it take's it own sweet time to get there. Do I need to bleed the line. If so, is that a bleed screw on the right side of the needle valve in the pic below.

Or could it be the snubber. As I was typing this, I found the instruction's for the snubber. It say's, "If the instrument seems to be sluggish or to lack responsiveness to transient pressure change's within the system, the next more porous snubber should be used".

So what do you guy's think. Thank's.

 

no , if you want to bleed it do it at the back of gauge your snubber is not porous enough, for anything i use one for i like mine as yours is now

 

I went on a short run today with my trailer. The gauge was slowly loosing pressure , then back up , going up and down big hill's. Would that be the snubber issue, or air in the line.

 

no , that is normal, under load the pressure will drop make a note of the loaded reading , when it drops a couple of pounds more than this it is time to change filter

 

I just changed all filter's. The pressure dropped from 22psi to 16psi. I think there's something else going on. I never had this kind of drop before.

 

I know you don't want to hear this but.....get a fp gauge with an electric sender and you'll be much happier.

 

I would not get an electric gauge, JMO. It seems like every electric sender fails, quickly.

I'm not running a needle valve, even though I probably should be. But anyways, compression fitting to 1/4" air line, into cab into a snubber then to the Isspro gauge. I did run the 1/4" Parker airline inside of a larger Parker airline to help insulate and protect from damage. When I just turn on the key, the pump primes. The gauge will jump up to about 10 psi. Then I start the motor it it jumps (not lightning speed, but quick) to 21.5 - 22 psi. And stays there idleing. Light throttle it'll drop tp 17 - 18 psi. Cruising speed on the freeway it'll sit at about 19-20 psi. WOT it gets to 15-16 psi. Even while cruising, the pressure will move around abit depending on terrain. When I start climbing freeway grades/hills, it'll drop a psi or 2. The pressure will drop and rise depending on injection pump needs.

 

Well it sound's like your's is messed up too. Maybe I'm wrong though. I had mine with an isolator and anti freeze in the line. It only fluctuated 1 or 2 psi, ever. Not the 8-10 we are seeing now.

Where did you get your snubber. Maybe you have the same problem,,,maybe not. Diesel Manor say's the snubber goes farthest away from the gauge.

I just orderd the fancy smancy $26 snubber from them. I'll see if it perform's any better.

How about you other guy's. How fast does your gauge work, and what snubber are you using, if any.

 

My snubber is an Isspro, and the instructios say to mount it on the back of the gauge (also Isspro). And I KNOW mine is working correctly. I've connected my Snap-On analog fuel injection fuel pressure gauge to 1/8" port right next to where the compression fitting mounts. And the readin are almost identical. The Snap-On gauge has a more defined, larger pressure grid. So the speed of the highs and lows seem different, yet the pressure values are the same.

 

you are ok you have the fass system that gives higher pressure than stock our stock is about 10 lbs max and drops about a pound , the cp3 is not like the vp44 it does not require fuel for lube or cooling where the vp44 can not go below 4 psi under load come commercial cp3 equipped engines do not even have lift pumps and work in vacuum , the hot roders are the only ones that might be worried, at huge hp draws you do not want the rail to run dry

 

Wich snubber do you have. The $4.00, or the $26 one. I'm guessing the $26 since you say the intruction's say to mount it to the back of the gauge. The cheaper one say's mount it furthest away from the gauge. Does it have the 3 little piston's that you can change. If so,,,that's the one I ordered too.

Also,,,did you bleed the line in any way.

 

the advantage of mounting a snubber closer to the pump it eliminates noise from vibration of the copper line to the gauge you can run even a cheap gauge a week or two with out it vibrating it to death with out a snubber or needle valve , note the average needle shake reading while driving and that is what you will see when the snubber is installed

 

No. It pretty much did it's own self-bleed. I've even had to disconnect the line at the pump for various reasons while working on the truck in general. I reconnected it and voila, everything works fine each and every time.

 

I have a needle valve but still get some pulsing noises from my gauge, how's a snubber work?

 

the snubber is a shock absorber the $26 comes with 3 pistons the fluid surges has to overcome the inertia of the piston. you size the piston by the viscosity of the liquid , others work like a muffler some use a bladder and some are more like the isolator with a diaphragm. cant spell but maybe you can make it out