Fuel Filter Gauges - Necessary or Not?

[Wotname]

Originally Posted by Capt Gill

Count me in on the Beta and definitely analog. My present Racor gauge is has a range of 0 hg to 30 hg with colour white ranging 0-7 hg, yellow 7-10, red 10-30. I guess Racor didn't see a need to account for positive press. Gravity feed or installing the Racor downstream of the lift pump would be an issue. I don't want a mech. gauge any further away than it is(top of the filter).

You are in
Thanks for the numbers, that is very helpful
Positive pressure only a small issue as the transducer I'm thinking off goes from 0 to 30 psi absolute so that is 15 psi (7.5"Hg) either side of the standard atmosphere or what you and I call 15 psi vacuum and 15 psi positive. It is just a case of providing a suitable meter for whatever section we want to observe.

[Wotname]

Originally Posted by GrahamHO

I appreciate what you are all trying to achieve with a pressure gauge. I didn't realise that blocked filters could be so common. I wonder if the same energy that is put into detection could better be put into keeping the fuel clean in the first place. I recall seeing large funnels that have a filter built in, once being used to refuel small aircraft. Also how vulnerable are your filler caps to letting water in? Maybe in a location with dodgy fuel the primary filter elements should be changed regularly. Then an inspection of the old element will tell you something.

I don't think blocked fuel filters is a problem with long distance trucks so why is it a problem with our boats? A truck might use in one day more diesel than I would use in a few years. Do trucks fit a fuel filter pressure gauge? I don't know.

Like you, I have never had a blocked filter - ever; and like you I am also quite pedantic about keeping the whole fuel system "clean"!

I had a thread about the occurrence of blocked filters awhile back and more didn't have a problem than did.

But enough people have had blocked filters and it's stops them dead in the water and unexpectedly. Mechanical gauges probably suffice for many but in a small boat (30') without an engine room, they just aren't practical IMO.

In some ways, this is more of a fun project than a necessity but if achievable for small(ish) dollars and effort, it might be something to look while motoring .

Might be a sign of ageing but these days I want to see real time temps etc than rely on idiot lights and alarms as in the past and so it is with fuel delivery. Perhaps also a case that technology has made all of this much easier than in the past.

Some helicopters have fuel filter idiot lights but these normally operate well before the engine goes quiet and these guys are very pedantic about fuel!!!.

Dunno about trucks!

[HappyMdRSailor]

Originally Posted by Wotname

Hmm… you experience is somewhat different from mine w.r.t. non metal tubing. Most small / light general aviation use PE or nylon tubing for their pitot and static air systems (airspeed and altitude), IME they fail reasonably often. Some of the runs are complex and I run a mile when they report problems as chasing small leaks is time consuming and frustrating (at the best). And a leak in their systems doesn't shut the engine down

I accept that metal (Cu or Al) tubing is far superior, at least it is IME.

YMMV

HA HA...

That's funny... Two guys with reasonable experience are tasked with the same tube run, and there's only one coil each, Al/Cu and PE/Nylon... And we both end up happy...

Your experience would DEFINITELY cause me to rip the metal tubing outta your hands! I guess I go by what I'm used to.... Static installations and long runs... But metal fatigue worries me on a boat more than it really should... Also, I figure high pressure hydraulics have been Nylon on boats for years... Of course every damn fitting leaks now that I think about it!

***starts marketing plan for nylon/pe lined metal tubing***

[captain58sailin]

On all of my previous vessels, I never had a vacuum gauge, nor at the time did I feel the need for one. On my current vessel, the gauge came with the boat, and after having some issues with contaminated fuel, I saw how it might come in handy. I keep a pretty tuned in ear for any variations of RPM that might indicate an engine (Fuel) problem. Like some of the previous posters I am also maniacal about not introducing contamination at the source, to limit the chances of killing my engine at the most inopportune time, which is when they always die. The gauge is mounted on the manifold that supplies both the gen set and the main, down stream of the dual filters, it does have the colored arcs and it is a good quick check when I am in the engine compartment. I built my own dual racor system that I can change filters on the fly, for about 20% of what the prefabbed systems run, but I already had both filter housings and all I had to hire out was the pipe bending and that was cheap. Would I go out to try and install a gauge on an existing system? My answer would be "depends" on if I was familiar with the system and if I was fairly certain that the tankage was clean, if the answer is yes, then I probably wouldn't go to the trouble, because of my handling of the fuel before it goes into the tank. In my current case, I became aware of contamination in the tanks fairly soon after I bought the vessel, and have taken measures to clean up the fuel as I go, I installed a passive centrifuge between the tanks and the filters, which gets drained religiously and that has eliminated the fuel filter plugging so far and eventually I will get all the crap out of my tanks and I will be a happier camper. I was going to post a photo of my setup, but for some reason the program here won't let me browse my computer for photos to upload. If the run wasn't so long, I would favor a second gauge on my instrument panel.

[GrahamHO]

Originally Posted by Wotname

Like you, I have never had a blocked filter - ever; and like you I am also quite pedantic about keeping the whole fuel system "clean"!

I had a thread about the occurrence of blocked filters awhile back and more didn't have a problem than did.

But enough people have had blocked filters and it's stops them dead in the water and unexpectedly. Mechanical gauges probably suffice for many but in a small boat (30') without an engine room, they just aren't practical IMO.

In some ways, this is more of a fun project than a necessity but if achievable for small(ish) dollars and effort, it might be something to look while motoring .

Might be a sign of ageing but these days I want to see real time temps etc than rely on idiot lights and alarms as in the past and so it is with fuel delivery. Perhaps also a case that technology has made all of this much easier than in the past.

Some helicopters have fuel filter idiot lights but these normally operate well before the engine goes quiet and these guys are very pedantic about fuel!!!.

Dunno about trucks!

Thanks Wotname: doing a quick Google search I see the average large truck in USA travels 120000 miles / year @ average 6 mpg diesel. Rounding out the figures and using 4 litres / gallon ( between US and Imperial) if my math is correct I make that 220 litres / day. On that amount of fuel I could very conservatively motor more than 500 miles which is roughly 2 years assuming I use my engine 1/2 of the time.
Now as I change my filters every year, that is similar to a truck changing its filter twice a day. Of course doubtless they have larger filter capacity.

Doing another Google search I find there is an aftermarket filter pressure gauge available for trucks which suggests to me that the factories don't fit them. I'm not sure though if that applies to large Kenworth / Volvo / Mac etc. however I don't believe they change their fuel filters every day.

I've been fortunate to have been a passenger in many helicopters both military and civilian ranging from Blackhawk right down to Robinson 200. The only times I've experienced warnings was in an Australian Airforce Iriquois 50' over breakers on a remote Samoan island we lost steering and landed on a beach. Another time the red power over load light was on in a civilian chopper in NZ when we were in a downdraft in a ravine. So I'm very aware and grateful chopper pilots are pedantic about fuel and safety in general.

[Capt Gill]

Originally Posted by Wotname

You are in
Thanks for the numbers, that is very helpful
Positive pressure only a small issue as the transducer I'm thinking off goes from 0 to 30 psi absolute so that is 15 psi (7.5"Hg) either side of the standard atmosphere or what you and I call 15 psi vacuum and 15 psi positive. It is just a case of providing a suitable meter for whatever section we want to observe.

Addendum: maybe over the top,but since it seems u r getting into this project it'd be cool to have a simple self test built into the gauge/sensor unit something along the lines of the OP buzzer,turn key on "buzz", kill eng."buzz". However if gauge needle will move to a fixed spot from key off to key on I'd be happy with that.
Again,I'd like to monitor as much as practical as to the engine condition for the same reasons the instrumentation in a plane's cockpit differs from what's found in a '72 Chevy.

[Capt Gill]

Originally Posted by Wotname

You are in
Thanks for the numbers, that is very helpful
Positive pressure only a small issue as the transducer I'm thinking off goes from 0 to 30 psi absolute so that is 15 psi (7.5"Hg) either side of the standard atmosphere or what you and I call 15 psi vacuum and 15 psi positive. It is just a case of providing a suitable meter for whatever section we want to observe.

Addendum: maybe over the top,but since it seems u r getting into this project it'd be cool to have a simple self test built into the gauge/sensor unit something along the lines of the OP buzzer,turn key on "buzz", kill eng."buzz". However if gauge needle will move to a fixed spot from key off to key on I'd be happy with that.
Again,I'd like to monitor as much as practical as to the engine condition for the same reasons the instrumentation in a plane's cockpit differs from what's found in a '72 Chevy.

[markpierce]

When insufficient fuel-flow is available for desired speed, the filter needs to be changed, either by switching to a new filter using a dual-filter set-up or replacing your single filter.

[jhulmer]

Originally Posted by skipmac

Curious as to how the injector pump was damaged. If the filter clogged it would restrict fuel flow to the pump but unless the filter ruptured and passed dirt to the pump I don't understand how it was damaged by limited fuel supply.

Skipmac, sorry for the slow response. I just noticed your question.

The only answer I can give you is the one the repair facility guy gave me when I asked if a clogged filter could damage the injector pump? and his simple answer was "yes".