Dual diesel filtering fitments

[[2574]]

I'm keen to have a dual diesel filtering arrangement so that I can switch from a blocked to a clean filter instantly and then replace any blocked filter at leisure. I am considering the pre-formed dual filter units such as this:

http://www.hyphose.co.uk/75500max30-484-p.asp

Has anybody hereabouts experience of fitting such a thing? Is it a DIY job? Don't see why it shouldn't be; just redirecting the supply pipe from old to new and connected the upstream side. Should be simple?

TIA

Rob

 

[rogerthebodger]

I made up a change over fuel filter arrangement using 2 standard CAV filters heads, 2 three way fuel valves and some fittings sorted out by my local hydraulic fittings supplier.

Works very well as long as when you filter elements you bleed both filters.

My setup was a lot cheaper than that you posted 600 GBP I think is a rip off.

 

[SimbaDog]

At that price I would expect they send a bloke round to fit it foc

 

[pvb]

The Racor system is very good, but it's big and very expensive. And, at 680 litres/hour, perhaps rather over-specified for your engine.

It's easy to make up a twin filter system yourself with a couple of filters and some valves. You can use cheap and cheerful CAV filters, or go for spin-on filters instead. I prefer simple on/off valves, and you only need 2 (either on the 2 inlets or on the 2 outlets). This enables you to run on one filter, with a clean spare filter in reserve, which you can instantly switch over to. It also, if required, allows you to use both filters in parallel if they both start to get blocked. With this system, you can't replace a filter element with the engine running - indeed you can't do that with most twin filter systems.

My old HR had a twin CAV system, fitted by the first owner, and it worked well. I added a Racor vacuum gauge, which indicates when a filter starts to get blocked and needs changing. In normal conditions, filters last ages.

 

[prv]

It's definitely worth fitting a dual-filter system and a gauge, as pvb describes. I've done it in both our boats, once with a packaged dual-filter unit (not the same as in your link, but the same idea and also massively overpriced) and once with ball valves and copper tubing. In fact the home-made version was arguably the better of the two, as it allowed a filter to be changed when running on the other one, and the valve handles were arranged so that the in-use filter had a handle across it, blocking removal, and the isolated filter was invitingly clear.

The vacuum gauge on Ariam is mounted next to the companionway steps, so I can keep an eye on it each time I go from cabin to cockpit. When we had a serious bug/sludge problem earlier this year, I would check the gauge each time before heading into confined waters, to be sure the engine wasn't going to die on me (it died numerous times at sea).

Finally, either use filter housings with a built-in priming pump on top, or have a separate squeeze-bulb pump between tank and filters. This makes changing filters and bleeding a doddle.

Pete

 

[Trundlebug]

Here's mine, with 2 valves per filter to enable changing whilst running.
All the fittings and parts cost around £100 from ASAP.
Plus about £15 for the pipe bender from ebay

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[[2574]]

The Racor system is very good, but it's big and very expensive. And, at 680 litres/hour, perhaps rather over-specified for your engine.

Yes I agree, hugely over specified, but the over engineered capacity is not without benefit I think as the fuel will be constantly circulated (back via the return lines from the injectors) and repeatedly filtered. I'm assuming that the amount of fuel filtered is a function of the fuel lift pump capacity.

 

[Stemar]

I made my own with a couple of filter holders from a car breaker and 4 taps and a few other bits & pieces from ASAP. A couple of hours to make and total cost 1/10 of the Hyphose job.

I'll be changing both this year 'cos they're getting pitted with rust. The cartidges are a bit dear at £11 a pop, but after 10 years, I probably shouldn't complain.

 

[pvb]

Yes I agree, hugely over specified, but the over engineered capacity is not without benefit I think as the fuel will be constantly circulated (back via the return lines from the injectors) and repeatedly filtered. I'm assuming that the amount of fuel filtered is a function of the fuel lift pump capacity.

Interestingly, the Racor website suggests the max flow is only 450 litres/hour, still more than adequate! Fuel is constantly circulated back to the tank in most (but not all) engine installations, so the actual amount flowing through the filter may be several times the actual consumption. However, for a yacht engine it will still be a very small flow rate for the Racor system, and I doubt whether it'll be enough to give the "centrifuge" effect which the Racor uses to spin off dirt and water.

 

[lw395]

I'm keen to have a dual diesel filtering arrangement so that I can switch from a blocked to a clean filter instantly and then replace any blocked filter at leisure. .....
Rob

I've heard it said that if a filter suddenly blocks, and you switch over, it's very probable that the other filter will block very quickly too.
Particularly on a yacht where the normal cause of blockage is a dirty tank getting shaken up.
So there might be very little leisure in which to change the filter?

How many people have actually changed over in anger on a sailing boat?

 

[[2574]]

I doubt whether it'll be enough to give the "centrifuge" effect which the Racor uses to spin off dirt and water.

That's an interesting observation and a good question for Racor.

 

[[2574]]

So there might be very little leisure in which to change the filter?

Agreed, but it might be enough to make a critical difference.

 

[lw395]

Agreed, but it might be enough to make a critical difference.

Indeed it might.
But I've seen two engines not starting this year due to air leaks in fuel plumbing.
You have to balance introducing a whole lot of failure points against the ability to get around one particular failure for a while.

I guess filter blockage will be more common in some places than others?
Also it will be different for an engine flowing a lot of fuel every month and slowly blocking the filter.

 

[pvb]

I've heard it said that if a filter suddenly blocks, and you switch over, it's very probable that the other filter will block very quickly too.
Particularly on a yacht where the normal cause of blockage is a dirty tank getting shaken up.
So there might be very little leisure in which to change the filter?

How many people have actually changed over in anger on a sailing boat?

Unless there's a lot of crud in the tank, the filter tends to clog gradually, eventually leading to so much resistance that the engine falters and ultimately stops. I experienced the faltering when I had a dual filter set-up, and changing to the other filter resolved the problem immediately, and allowed me to motor safely for the rest of the day.

 

[Freebee]

due the large amount of pleated media inside the filter, it would be very unusual for the filter to block "suddenly" what you describe as a sudden blockage is more likely in a mesh type strainer where the filter area is limited. Yes a dual filter set up increases the chances of air leaks if its not done properly, but dual filtration sets ups are very common in large commercial or naval sets ups..... why would they do that if it was not thought to be extremely beneficial?

 

[[2574]]

That's an interesting observation and a good question for Racor.

I have spoken with Parker this afternoon and they respond that with the 500 Turbine series the fuel volume and speed is not critical for water and particulate separation the bulk of which happens in the filtration media.

 

[pvb]

I have spoken with Parker this afternoon and they respond that with the 500 Turbine series the fuel volume and speed is not critical for water and particulate separation the bulk of which happens in the filtration media.

Seems that their "turbine centrifuge" technology may just be marketing hype after all!

 

[KellysEye]

.>Dual diesel filtering fitments

I fitted two Racor filters in parallel using hose and on/off switches it's easy. Don't forget to bleed both filters

 

[macd]

I made up a change over fuel filter arrangement using 2 standard CAV filters heads, 2 three way fuel valves and some fittings sorted out by my local hydraulic fittings supplier.

Works very well as long as when you filter elements you bleed both filters.

My setup was a lot cheaper than that you posted 600 GBP I think is a rip off.

+1 to all that.
I used a pair of CAVs: access is extremely good. If it weren't I'd have gone for spin-ons. Both filters have built-in doughnut pumps, which makes priming a doddle.
The valving (perhaps yours, too) allows switch-over (and filter change) with the engine running.
All conducive to greater peace of mind (does everyone worry more as they get older?)
IICGWSOLIW

 

[[2574]]

The vacuum gauge on Ariam is mounted next to the companionway steps, so I can keep an eye on it each time I go from cabin to cockpit. When we had a serious bug/sludge problem earlier this year, I would check the gauge each time before heading into confined waters, to be sure the engine wasn't going to die on me (it died numerous times at sea).

Would you rate the vacuum gauge as an essential part of the setup? I can absolutely see that being aware of an upcoming problem is much better than a surprise! However the gauge is £80 + VAT so near enough £100. This then starts to justify the cost of the pre-formed kits.