fuel vacuum gage

[tomcat rio]

i put one in downstream of the filter in parrelel with a tee fitting. i also installed and audio alarm. the engine runs fine, but the gage never moves.
what readings do other folks here get on their fuel vacuum gages?
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the insatllation instructions did not specify a reading.
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http://www.borelmfg.com/products_wet_exhast_alam.htm

[Mariner]

The whole point of the vacuum gauge is to tell if your filter has become clogged. You will notice that the vacuum will increase or decrease (depending on where you installed it) as the filter accumulates debris. When this happens, it is an early warning that your filter is about to become clogged and impact the engine's performance.

Basically, you're supposed to be watching for change over time. I suggest recording it in the log once on every outing.

[tomcat rio]

..the gage never moves off zero.

[DougSea]

..the gage never moves off zero.

That implies you have very little restriction in your filter (or something's wrong with the gauge!)

Think about drinking a glass of water through a straw - your cheeks don't pull in much and you get a good flow of water. Then switch to a cold milk shake (representing a clogged up filter) - your cheeks (gauge) suck in and you get hardly any flow.

Try shutting off your fuel supply before the gauge (fully or partially) and cranking the engine - that ought to get some movement out of the gauge.

You do have a vacuum gauge, right? The picture looks like a pressure gauge, the opposite of what you need.

[AlMar]

I get a reading of about 3 with a new filter. I'm useing a 10 micron Racor (moved down from the 3). When It gets up to about 5-7 I have to pay some attention to the filters. I have two gauges (one on each filter) and one at the instrument panel; the two in use always read the same, so distance from the filter or fuel tank doesn't seem to affect them.
AlMar

[tomcat rio]

sent this to the manufacturer:
from ed flanagan, mattituck new york....what vacuum level trips the sensor?...i'm pretty sure my gage and sensor are installed properly, but the gage has never moved off zero. i've checked it at several power levels. would this be normal?
thank you.
ed flanagan
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his response:

Hi Ed. With clean filters the reading will .5 to 1" Hg. This would be with the engine loaded. So you may not see a reading at this time until the filter have some run time. The vac alarm is set for 7" Hg. Typically a diesel can run even up to 10" Hg. ( I have had customers with this problem do to clogged pick up tubes.)If you want to do a test, carefully, very carefully, close down the diesel shut of valve very slowly and see if the vac gauge starts to provide a reading off or near zero.But, I do not recommend doing this.If you have any other questions, please advise. Regards, Van TaiariolBorel Mfg Inc.

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[tomcat rio]

see link. slide halfway down.
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http://www.borelmfg.com/products_wet_exhast_alam.htm
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the phantom and tomcat jets had 'fuel pressure' caution lights, but no fuel pressure gages. as i recall, that meant we couldn't select afterburner (2000 pounds or 300 gallons a minute fuel flow). maybe the lights in the jets should have been labeled 'fuel vacuum'.

[chiefrcd]

Tomcat...you're just not sucking enough bro...

[Russell]

I recently installed the vacuum gauge that mounts on top of the Racor filter housing and it did not register anything at cruise. At wide open throttle the needle moved just a little. The gauge shows up to 10 in. Hg in green and then turns to red. I plan to change the cartrige when it gets to 5. I have to open the hatch to see the gauge, but I like the simplicity for the sake of reliability.

[tomcat rio]

...some stuff you don't have to watch every minute.
one good deal with the 28 TE is that you can leave the helm to do the check and the boat won't care.