Noisy F. P. Gauge

[Big White Beast]

I am trying to save up for my transmission mods and didn't want to drop a lot on a fuel pressure gauge & senders. So I went with a mechanical gauge & pre-made 4' braided line.



As if these Ram's aren't noisy enough (Besides the wonderful purr of the Cummins ) Now I have the noise from the VP44 transmitted down the line into the cab. I went from the schroeder valve by the filter too, not the one by the VP44. Not noticably bad at speed, truck & radio make enough noise by then. Idling it's really noticable. I tye wrapped the line as well as possible to stop any vibration, you can actually feel it pulsing, but it's still noisy.



Guess I'll have to ante up for the electrical stuff after my mods.



The good news is 14 PSI at idle and never got it to go below 6 PSI and 7 to 8 at freeway speeds. Just changed my filter 2 weeks ago so I'm sure post filter is near the same. I'll probably monitor both if I go electrical.



Just my 2¢ worth,



Garrett



P. S. KAT when I checked with XK they raised the prices on the gauges, $59 now, senders $39. And only with a chrome bezel. Salesman said there was a run on these by diesel drivers Go figure!

 

[SEmerson]

I had the same problem. I wrapped the braided line with electrical tape and then put heat sink on the whole tube. Worked great.

 

[dieselboy25]

What noise?

I have my mechanical fuel pressure (Autometer) mounted in the top hole of my three hole pillar mount and I have never heard anything noise or vibration. I also have braided line from the firewall into the cab up through the pillar.

Eric

 

[SEmerson]

mine was very noisy.

 

[illflem]

Add a gauge snubber or needle valve to the end of the line closest to engine. The noise will go away and the gauge will last longer. This one worked for me.

 

[Big White Beast]

Do they make smaller ones?

I see in the link that the thread is 1/4 NPT, I am currently hooked up to the schroeder valve with a -4AN fitting. I would need several adapters to configure it again. I was looking at Geno's banjo bolts and they are tapped at 1/8 NPT. Was wondering if a snubber is available in that size. My typical experience with plumbing is keep it simple as possible to avoid leaks.



Besides Schroeder to -4AN adapter to 1/4 NPT to snubber to 1/4 NPT adpter to -4AN would end up about 6" long



I do like the idea of having a shut off availble if the unthinkable happened. Besides putting the schroeder back in, Guess I should keep it in the truck instead of the tool box at home



Garrett

 

[SEmerson]

what is the snubber valve for? What applications is it used in? Just trying to figure out where to find one and what to ask for.

 

[illflem]

Gauge snubbers are used on hydraulic, steam and high pressure pump systems to protect the gauge from rapid pulsations. A hydraulic shop or ag equipment supplier are good sources. Most widely used gauges are 1/4" NPT and the snubber is installed right on the gauge, it may be difficult to find one with different threads. Needle valves are made in all sizes though and will work just as well. All a snubber is a solid fitting with a VERY small hole though it. Some folks make their own by filling a fitting with solder or brazing then drilling a hole. The way I got around using a bunch of fittings, I needed 1/8"NPT, was to install a 1/4 to 1/8 bushing in the female end of the snubber. On the male end I tapped 1/8" threads into the inside of the fitting, the ID is exactly the right size for a 1/8" tap. This only added 1/4" to the length of the valve I linked to above. Another option if you are using braided line would be to cut it and install 1/4" fittings in a part of the line that is easily accessible. Yet another option would be to take your Schroeder to -4AN fitting to a machine shop and have them weld it shut then drill a hole. We're talking a hole just a little larger than the diameter of a human hair. My experience has been if you don't use a snubber even on an electric gauge that the sender won't last long, on a mechanical the gauge will go out. 12 valves are much worse than 24s for fuel pressure pusation.

 

[Big White Beast]

Illflem, Thanks for the info......

I did a search last night and think I found one that will work. It doesn't have the shut off feature though. I would prefer it in the engine compartment though. I can hear the noise down the whole line. The gauge does pulse but not really bad. A liquid filled gauge might slow that down but I hear they are slow to respond.



Anyway you have given me several ideas that I think I can incorporate. I might just pick up a -4AN and braze it shut then drill it. I have some tiny drills. Looks like "the little shop that could" will get some action this weekend



Thanks again for the info,



Garrett

 

[Double 6]

You may be able to find a small 1/8'' sized needle valve at a oil and gas supply store. Just a suggestion anyway.

 

[SEmerson]

After I covered my line the sound is pretty good. But the hose still viberates and sometimes i have to move it around a bit. So the snubber valve sounds good. I looked all day for one with no luck. So what i did was to take the valve that is in the injector pump line connection that i had removed. Whe I put my fp line on and cut the center out then crip it down to a small hole. Line vibration is way down.

 

[Ron Bissett]

Use fuel hose and leave some slack ,15 psi don't require any braid only if for show, as for snubers any hardware store has brass fittings and brass plugs a small orffice from a furnice RV will work or a small drill will do the job , use any place in line ,slows flow , just hose with plenty slack loop if needed will take out the shock to line , Last ten years testing stuff for US Navy (OEM test) NOSL. (closed) 94. Ron in Louisville KY