NOT changing the primary fuel filter every year?

Hi
I would definitely say it's worth changing every year. Surely at little expense and effort ?
The primary is the first line of defence against the odd and random slug of poor and/or water saturated fuel.
As for the condition based monitoring theory...as an engineer, I'm all for that, but not in a boat. If a shore based engine/generator/turbine or whatever breaks down...it stays where it is until someone can fix it and lives are seldom at risk....Boats don't and are a different matter.

Yes to everything you say and add that with the advent of bio fuels we should check the lift pump valves and its strainer. We just returned from a cruise to south Netherlands and on return the tank drain showed far less grud than expected after rolling around the north sea for 36 hours. I changed in-line and engine filters as planned after the trip but then the engine suffered repeated bouts of fuel starvation. Having checked filter seals and pipe connections the only thing left was the lift pump. In the head was a well hidden strainer which was completely choked and both valves were gummed solid. A replacement pump cost £26+vat+p&p from Parts4Engines. How long we had been running on a static feed from the tank I have no idea but the added effort of checking the lift pump and filters each year beats the hassle of drifting down tide and wind through the moorings at 3 knots!
 
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I am perhaps the only person who was glad to switch from Racor to CAV. I used to begrudge putting in a new £15 filter element if I suspected a problem. Then when I changed boats, I inherited a CAV filter, fortunately in a very accessible spot, and bought a ten pack of filters for £12. So I can, and do, change filters as though I were changing my socks- the slightest hiccup or hesitation and I will shove a new filter in. At that price it's an absolute no brainer.
I would also say that it's worth being familiar enough with filter changes that you can do it in the dark with your eyes closed.
 
I don't think I will be skimping on annual fuel filter changes despite having two engines . The filters cost on average only £5 each.

A little spillage from the engine mounted fuel filter it inevitable in my case too .
I use an old 5 lite clear plastic water bottle with the top cut off to drop the removed filter into. The fuel and the filter may then be inspected. An oil absorbent pad deals with any spillage under the engine. I have heard of a nappy being used, which obviously only needs cheap budget brand so is surprisingly cheap .
So try to improvise or make something cheap and simple to catch manage spills .
 
The installation instructions for my BUKH DV10 do not require any filter between the tank and the lift pump. The only filtering being done by the disposable cartridge filter on the engine, which is downstream of the lift pump.
However, on my boat, a previous owner fitted a CAV filter between tank and lift pump and I replaced this with a Racor filter, which is very accessible and it is easy to change the element without mess.

Having now got this Racor filter, I can’t see why I still need the filter on the engine, which is messy and awkward to change and invariably lets some diesel fall onto the engine mount below it; which rots it. I’m thinking of doing away with this filter altogether and just relying on the Racor.

Anyone see any objection to this?

I did exactly that with my diesel generator engine. I bought a cheap spin on filter head from Ebay and removed the crappy little filter unit on the engine. The spin on filter is external to the generator acoustic box so is easy access. The filters are £4 each from motor factors. Works well as the filter is now huge compared to the old tiny engine mounted filter. I only change it about every three years or three hundred hours
 
I am perhaps the only person who was glad to switch from Racor to CAV. I used to begrudge putting in a new £15 filter element if I suspected a problem. Then when I changed boats, I inherited a CAV filter, fortunately in a very accessible spot, and bought a ten pack of filters for £12. So I can, and do, change filters as though I were changing my socks- the slightest hiccup or hesitation and I will shove a new filter in. At that price it's an absolute no brainer.
I would also say that it's worth being familiar enough with filter changes that you can do it in the dark with your eyes closed.
If you have a spin on filter you can do it in the dark with your eyes closed........:)
 
Having now got this Racor filter, I can’t see why I still need the filter on the engine, which is messy and awkward to change and invariably lets some diesel fall onto the engine mount below it; which rots it. I’m thinking of doing away with this filter altogether and just relying on the Racor.

My engine-mounted filter was awkward and messy to change too. Rather than doing away with it, though, I unbolted the housing from the engine, fitted longer hoses, and mounted it on an easily-accessible bulkhead next to the primary filters.

Given the crud encountered in boat diesel vs road fuel, I would not be inclined to reduce the amount of filtering.

Pete
 
Having now got this Racor filter, I can’t see why I still need the filter on the engine, which is messy and awkward to change and invariably lets some diesel fall onto the engine mount below it; which rots it. I’m thinking of doing away with this filter altogether and just relying on the Racor.

Anyone see any objection to this?

I do! Naturally, you will first make sure the Racor filter cartridge is a suitable spec; some boats have say a 30 micron primary and a 5/10 micron secondary. If using a single filter you'll have to go with the lowest in the line. But that's fairly obvious.

Think, however, about when you change the Racor filter; can you flat guarantee that no unfiltered diesel sneaks itself onto the downstream side, and that zero contamination is introduced during the changeover procedure?

If you can't, then you need the secondary; not so much as a filter in normal running, but as a goalie with a near 100% track record of safely catching the odd injector-destroying detritus, which somehow manages to slip through your otherwise formidable defences!

Now consider whether Mourinho would clean up a few diesel drips for one of those ;)
 
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Actually a lot more goes through the filter as diesel engines draw fuel from the tank and return unused fuel back to it, with the result that the filter does a lot more work than you might think.

Well, sort of. He's still only putting 100-150 litres per year through it, but he's putting it through many times. I suspect that's not a lot of extra work for the filter, because the fuel will never get very grubby.
 
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