Is it worth the expense of putting a pressure gauge onto the Racor

tudorsailor

tudorsailor

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Having had lots of problems with dirty fuel this season - which is still being resolved, I had the advice from the owner of a similar yacht, to fit a pressure gauge to the Racor. They apparently fit in the top in place of the T handle. Apparently then one can monitor the state of the filter and how dirty it is. Details are here
The gauge is only available from the States so costs £100+vat+carriage. This seems a lot for a simple gauge
So my questions are:
  • Is fitting a gauge a worthwhile exercise?
  • Is there a cheaper alternative to a badged Racor gauge
Will I save money by not changing the filters until the gauge says its time???

TudorSailor
 
Not bad, not bad price but...
If you have fuel lines such that adding a few t pieces wont wreck the system then there are better ways to go.

The product will only tell you the pressure after the filter, not what is more relevant, the pressure across the filter. Should to decide to roll your own then an electric/electronic differential pressure sensor with remote display would be the dogs.

edit: didnt like the tone of the first line
 
I would definitely recommend a vacuum gauge. Not having one is a bit like not having a fuel gauge, and filling the tank every 20 engine hours (or whatever) just in case. Except that the rate of filter "consumption" varies much more than the rate of fuel consumption, and rather than just topping up a tank you're throwing away whatever's left in it (the part-used filter).

As well as routine monitoring it's also helpful for diagnostics, if the engine starts stuttering you know instantly if it's fuel starvation and whether it's before or after the lift pump.

Fortunately, you don't need to pay the £100 for a special Racor gauge. A perfectly suitable one can be had from eBay for under a tenner, and tee-d into the fuel line between lift pump and filter. You can have a length of narrow hose between tee and gauge, allowing you to mount the latter somewhere visible instead of hidden away like the filter-top one.

Mine is next to the companionway steps, I've formed the habit of glancing at it on my way out of the cabin when under power. I also stick my head through the hatch for a quick check before proceeding into critical points like a tide-racked rocky passage in the Channel Islands. Exactly the same way my dad checks his "Ts and Ps" (a row of engine temperature and pressure gauges) in his aircraft before starting a manoeuvre.

Pete
 
prv said:
I would definitely recommend a vacuum gauge. Not having one is a bit like not having a fuel gauge, and filling the tank every 20 engine hours (or whatever) just in case. Except that the rate of filter "consumption" varies much more than the rate of fuel consumption, and rather than just topping up a tank you're throwing away whatever's left in it (the part-used filter).

As well as routine monitoring it's also helpful for diagnostics, if the engine starts stuttering you know instantly if it's fuel starvation and whether it's before or after the lift pump.

Fortunately, you don't need to pay the £100 for a special Racor gauge. A perfectly suitable one can be had from eBay for under a tenner, and tee-d into the fuel line between lift pump and filter. You can have a length of narrow hose between tee and gauge, allowing you to mount the latter somewhere visible instead of hidden away like the filter-top one.

Mine is next to the companionway steps, I've formed the habit of glancing at it on my way out of the cabin when under power. I also stick my head through the hatch for a quick check before proceeding into critical points like a tide-racked rocky passage in the Channel Islands. Exactly the same way my dad checks his "Ts and Ps" (a row of engine temperature and pressure gauges) in his aircraft before starting a manoeuvre.

Pete
Click to expand...

+1

I fitted one of these. http://www.banggood.com/2-p-906588.html Cost about €7 at the time. Whole project cost me less than €30 including buying a set of hole cutters, wiring and switch for the light, a T-piece and better fuel hose than the plastic pipe that came with the gauge.
 
So this goes between the (coarse) filter and the engine? What sort of length can the tee off be? Sounds a brilliant idea!
 
Kelpie said:
So this goes between the (coarse) filter and the engine? What sort of length can the tee off be? Sounds a brilliant idea!
Click to expand...

That's right. I don't know whether there's a limit to the length of the gauge hose; to a first approximation the pressure inside it ought to be the same everywhere, but maybe there's eventually some kind of fluid-dynamics limit or an effect from the hose being sucked inwards ever so slightly? Anyway, mine's a couple of metres and works fine. I routed it with a loop upwards from the tee so that it doesn't have diesel in it, but I'm not sure that's actually necessary. Perhaps allowing diesel into the hose and gauge would actually improve accuracy by being incompressible? The advert does say suitable for oil.

Pete
 
Kelpie said:
So this goes between the (coarse) filter and the engine? What sort of length can the tee off be? Sounds a brilliant idea!
Click to expand...

Yes.

Mine is about 2' from the T. I fitted it discretely in an aft cabin, but it does mean I have to go into that cabin and kneel down to view it. Sounds like prv may have had the better idea.
 
We have a Racor gauge. Bought from ASAP supplies. Personally I have found it very useful in determining when to change the filter.
No need to buy from the States especially with current exchange rates.
 
I'd support the view that a vacuum gauge is a good idea, but I think it needs to be remotely mounted somewhere where it's easy to see - I had mine on my last boat on the switch panel. The Racor gauge is good, and is fluid-filled, and can be bought from ASAP Supplies. You can mount it some distance from the fuel piping, mine must have had about a 4 metre pipe run.
 
prv said:
I suppose so, although it looks like more effort and complication for no obvious benefit in a typical yacht installation.

Does it sense vacuum rather than positive pressure? Not quite clear from the description.

Pete
Click to expand...
Not sure, looks like 20kpa to 250kpa - whats that - 0.2 to 2.5 bar? How low does the pressure on go?

I never really gave them much thought before, but it on my boat it would cost less than a tenner and a few wires, everything else is there already with a Raspberry Pi & arduino. Then it would record and could set an alarm. . Might be worth an afternoon and few quid on ebay.
 
GHA said:
Not sure, looks like 20kpa to 250kpa - whats that - 0.2 to 2.5 bar? How low does the pressure on go?
Click to expand...

The pressure between the lift pump and filters is negative, that's the point.

The analogue gauge linked above goes from 0 to -1 bar.

Pete
 
nigelmercier said:
Found a 3-way Fulham Nozzle for 8mm I/D hose http://r.ebay.com/fDRvQV

I have 10mm hose, so still looking.
Click to expand...

I made mine up from bits - a tee with three female BSP threads, two large hose barbs with male BSP threads, and a third hose barb with male BSP thread and very narrow on the barb side - 3mm ID or something like that. I only wanted a narrow little tube running to the gauge, not a great fat pipe.

Pete
 
prv said:
The pressure between the lift pump and filters is negative, that's the point.

The analogue gauge linked above goes from 0 to -1 bar.

Pete
Click to expand...
Says "absolute" pressure, doesn't that mean anything under 1 bar is negative? A vacuum is just a pressure less than air pressure?
Not sure. Anyone?
 
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