Remote filter vacuum switch

[CaptnBry]

A gauge to indicate if a fuel filter is clogging should be monitored at the helm, preferably with an alarm buzzer and/or light, IMHO.

Yet all the gauges i find mount at the filter, or are mechanical remotes ( no buzzer or switch).
Further complications arrises because the "trip point" varies wildly depending on many vessle unique factors.

So, where can i get an adjustable vacuum switch, diesel rated, please?

This seems obvious, but my Searches can't find anything even on Trucker sites.

Heck, i think i could fabricate one, but a diesel leak is forbidden on my boat.

Thanks in advance, Cruisers!

[Roy M]

I used to do a bit of delivery work along the Pacific coast. The most common issue for me was dirty fuel. Entering a restricted harbor in bad weather is not a nice experience. So, I made a simple alarm system using stock parts. First, I attached a Racor vacuum gauge in the cockpit, adjacent to the fuel gauge, and further, installed the small LED indicator lamps above it (more on this in a moment). To the rear side of the gauge I added a Racor vacuum switch. It is attached, via vacuum hose, and tees into the supply hose between the fuel filter output side and the fuel pump. As an aside, the fine particle fuel filter attached to my engine is in an awkward place to inspect and service, so I simply removed the filter element, installed a new filter assembly with fine filter between the filter assembly (because I have TWO standard 30 micron filters, with a selector for one or the other) and the fuel pump. Then, just because I can do it, I put water sensors in all the Racor fuel filter bowls. So, here's how it is to live in my paranoid world of having lost my engine entering a crowded harbor in rough conditions. As I'm entering the harbor, distracted by the heavy breakers and fatigue, the fuel in the tank well shakened by the rough seas offshore, chooses THIS MOMENT (Murphy's Law in action) to plug the fuel filter in use. Hearing the characteristic increase in RPM , before shutoff by fuel starvation, hearing the alarm buzzer (each alarm in my boat uses a different time frequency), glancing at the instrument panel to see the red LED lamp above the fuel gauge (the second LED, bright yellow, warns of water rising in the fuel filter, also with its own characteristic buzzer tone), and for repetition, the fuel vacuum gauge displaying its needle in the red zone, I make a quick leap below and switch from one filter to the other. Instantly, the engine gets its grip, the alarm shuts off, the vacuum gauge drops into it's normal state and I holler at someone for a fresh cup of coffee. I also have alarms and buzzers for rising water in the bilge, the engine overheating from a shutoff of cooling water supply (plastic bag or kelp blocking the intake filter) or loss of a vane on the impeller, meaning overheating within minutes, or an overheating for other reasons (loss of antifreeze, thermostat issues, etc.), Electrical issues (charger, etc.), Oil pressure, fire alarm from Automatic Halotron Discharge, and to fully express my paranoia, a pair of switches at my bunk to declare my unhappinessbof unexpected visitors or things that go bump in the night. One switch turns on the High Output flood lights that turn night into day,.and the other that notifies everyone in the anchorage to come outside for a good show using strobes, 130 dB alarms (with voice translations in English, Spanish and French) that inform surprise visitors that this is their only warning and should go away while able. All of this stuff is available online. Some assembly required.

[thinwater]

McMaster Carr has several.


https://www.mcmaster.com/vacuum-switches/

[CaptnBry]

McMaster, shows one for $130 as splash rated, assume the diesel rating, i guess.

https://www.mcmaster.com/2957N11
$155usd
Is a diesel rated current loop Transducer, then make and calibrate your own gauge and alarm trip point in Arduino firmware and an LCD display from parts.

[RaymondR]

Since what you are mist interested in is the differential pressure across the filter rather than a value dependent upon other effects, such as the depth of fuel in the tank, a differential pressure transducer with a meter at the helm position may give better results.

[Bill O]

Originally Posted by CaptnBry

A gauge to indicate if a fuel filter is clogging should be monitored at the helm, preferably with an alarm buzzer and/or light, IMHO.

Yet all the gauges i find mount at the filter, or are mechanical remotes ( no buzzer or switch).
Further complications arrises because the "trip point" varies wildly depending on many vessle unique factors.

Thanks in advance, Cruisers!

Not really certain why you would want another idiot alarm instead of a vacuum gauge. While you can do various set points on the alarms, I like to see what is happening and notice a creep in the increased vacuum and possibly switch tanks/change filters before a real problem occurs.
On my last 2 boats have installed remote vac. gauges (not in the engine room)we can monitor if there is a problem before it gets too bad.
A simple automotive vac. gauge installed between the filter and engine is all you need to do the job, then mount it where is convenient/is easy to monitor.