snubber for fuel PSI / vacuum gauge

[scenarioL113]

Does anyone use a snubber for a fuel pressure or vacuum gauge in their fuel system?

I have cummins 4BTs and installed vacuum gauges on my filter heads which are remote from the engine. Both my engines send pulses of pressure from the lift pumps that cause the gauges to flutter aggressively at idle and dont level out until I am bringing the rpms up over 1300rpms.

Both my gauges have broke their needles from (what I think) slamming the stopper pin @ the "0" reading. I never in my life had a needle on a gauge break. Both engines are doing it so I do not think it is a mechanical problem issue. this just may be an inherent problem of the 4BT which is known to be a rattly and shakey engine at idle. When cruising tho they will put you to sleep in harmonic bliss...

Tony @ seaboard marine agrees that the engines seem to be "pulsy" but not abnormally so.

Just wondering if any one has had any similar disturbances in their fuel monitoring and had to install a snubber which can help in this type of situation. Snubber are listed as being helpful for PSI pulses but do not mention for vacuum issues.

My now broken Wika gauges are liquid filled and were not cheapies.
Here is a video that shows it but disregard the red drag needle (it was not adjusted properly and searched by itself)

https://www.youtube.com/watch?v=Toc5E6AyQbo

[Carl]

No, but they do work well at reducing the pulsations caused when pumping fluids.

[Rawleigh]

I think I had to get them for my Floscans.

http://www.floscan.com/html/blue/access ... php?aid=98

[Bruce]

Cummins have a penchant for violent pulsation on the fuel systems but it is normal.
If your fuel lines are steel braided or heavy wrapped cloth it won't allow fuel lines expand and contract to act as pulsation dampeners. I've had some luck with reducing pulsation by using red stripe rubber fuel hose and at times increasing to next size, i.e. 3/8 to 1/2.

I was a flowscan distributor and had many issues with them on cummins engines even with the pulsation dampers they came which were the size of a ph30 oil filter.

If you install dampers they have to be the highest point in the fuel system as they trap a bubble of air to work.

[Carl]

We may be talking about different things, the Snubbers I refer to are these

https://www.bucksales.com/chemiquip/snubbers/25.html


They have sintered elements crimped into the end which reduces the pulsations...there are others on the market which may function differently but can only speak to these.

[scenarioL113]

Yes, that is what I am referring to.
They seem to come in different types.

Some offer a very small hole to allow pulsations to be dampered and others that have some kind of porous material that acts kind of like a screen/filter (for lack of a better description by me) that produced the same end result.

Different liquids have different viscosity etc... that require a more or less porous "dampener" to adequately do its job with whichever liquid you are trying to damper.

From what I read on Dodge Cummin forums for the B-series was a snubber that has a .008 hole seemed to work for the fuel pressure gauges. I dont know if that will work for my particular application but will give it a try bc it is not expesive.

I am more concerned with dumping another $250 for a pair of gauges that I had to throw in the garbage after 60 hours of operation. It is frustrating when you try to do the right thing for proper maintenance and it still gives you a hard time...

Just like my CAV pump that was rebuilt by a local Delphi/CAV certified shop ($1300.00) in September 2020 (yes 2 moths ago) and it is still leaking fuel...
it works fine but still dripping diesel...gotta pull it AGAIN and bring it back....but that is another story...

[Rawleigh]

Frank, can you post a link when you find a snubber? I have one on the fuel pressure gauge of a 4-71 I have and I think it may be clogged as the new gauge shows no pressure.

Here is an inexpensive ISSPRO fuel pressure gauge you can try with the snubbers before you spend big bucks on a fancy gauge.

https://www.surpluscenter.com/Gauges/Au ... 1-1823.axd

[scenarioL113]

Rawleigh this is the snubber that some Cummins / DODGE guys are using on their 6BTs. Some of them suggest the .008 orifice hole but they also say you can try the ones that have multiple replaceable orifices

https://www.mcmaster.com/3820K52/

this one has a few different orifices that you can change to see what works best

https://www.mcmaster.com/3820K36/

Honestly I dont know anything about any of these things and frankly never even heard of one till I started researching my fuel pulsating problem....as usual I have to deal with another problem that most people never even heard of (seems to be the story of every project I have ever worked on...having idiotic problems that no one else gets...I can only laugh). (I cant wait for my next repower project...hehe)

[Rawleigh]

Thanks Frank! Should have known McMaster Carr would have them!

[Carl]

Thanks Frank! Should have known McMaster Carr would have them!

They have everything because they have a 50% markup over regular distributors and never budge on the prices.

That said my McMaster delivery will be here this morning between 9-11am as on top of their same day shipping, as everything is in stock, they ship every order RED Label Priority at standard shipping rates. So I'll pay more for the tooling, but save overall on the shipping as Red Label shipping would cost more then the tools...and I need then sooner then later. Its as amazing company and one of the best websites to navigate and order from.

[Rawleigh]

Yea, I have ordered from them at 6pm and had it on my desk the next morning by 11am at their regular shipping rate. Amazing.

[scenarioL113]

Yea, I have ordered from them at 6pm and had it on my desk the next morning by 11am at their regular shipping rate. Amazing.

I had the snubbers delivered by McMaster in less than 24hrs

I bought the .008 orifice 1/4npt male x 1/4npt female. I will install them with my broken gauges. (only the needles are partially broken) I will at least be able to see if the pulsating is corrected. The needles still work they just wont hit the stops. I will report back when I fire the engines which wont be for another 2 weeks.

I am installing them on top of the primary fuel filter housing. My primary filters are remote from engine and only connected by a rubber hose that is about 4 foot in length. I would have thought that distance alone would be enough to wipe out the pulsating but in my case I guess not. I guess the 4bt 150 is just pulsy with the 4 strokes and lift pump??? I would think the 6bt 210 would be the same but I guess not. (the 210 I think shares many attributes as its little brother...CAV pump and same lift pump???).
IDK just another idiot prob that will forever "only happen to me"....smh again...
(over $200 on high end SS gauges....right in the garbage... you try to do the right thing and you get bit)

[Rawleigh]

Frank: For that price have you checked on getting the gauges repaired? They may just need a new needle.

[scenarioL113]

I did speak to WIKA but I think it is a flat rate to repair and the cost was not conducive iirc. SBMAR has good gauges for $80 each. I will call wika again before I order. I dont remember actually what they said bc I was disgusted and it was before the winter.