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Shanaly · 13-09-2011, 04:34

does anyone know of such a thing for yachts? puradyn make some but seem to be large and expensive - are there any alternatives?. above all, how do I ensure extra inline filters maintain engine oil pressure?.

or is it enough simply to frequently change the oil/filters, say every 50 hours?

thoughts welcome! thanks in advance

**skipmac** · 13-09-2011, 04:42

The problem with oil polishing or ultra fine filtration is that it restricts oil flow and pressure and thus lubrication to the engine. I researched the subject and purchased a dual filter system from AmsOil that has one standard filter to keep the flow rate and pressure correct but at the same time diverts about 10% of the oil through a secondary, ultra fine filter so after a few hours run time all the oil will be "polished".

At least that's the theory and what the advertising says. Haven't installed or used it yet.

Badsanta · 13-09-2011, 04:45

By-Pass Filters and Mounting Systems

sailorboy1 · 13-09-2011, 05:13

Is there really any benefit to these systems?

They mostly are just removing particles by providing finer filtration. But particles aren't the real problem for most systems it's the contamination of the oil from by-products and these aren't going to be effected by better filtration.

Shanaly · 13-09-2011, 05:45

thnx for your reply

would the 'other oil contaminants' be the sort that get in diesel? - in which case, would any of the 'extra' diesel filtration arrangements be worth using on the lube oil? ( a separate 'sump', oil pump, and circuit would be required - a bit like the extra diesel cleaning circuit and day tank arrangement sailors sometimes use for fuel).

along those lines (ptp!) could one use a domestic water filter, (pressurised with a separate oil pump etc) - they are cheap high capacity and filter from 0.5microns as well as chemicals in water, which I suppose menas they would clean up lube oil as well...?

thnx in advance

sailorboy1 · 13-09-2011, 05:57

The "other contaminants" are chemical in nature things like sulfur (which becomes an acid problem) and nothing that a filter is going to remove (fuel additive more called for) . Engine oil does have additives to deal with this stuff up to a level.

The filters are only going to take out particles. A separator will take out water that will lead to emulsions.

A larger filter will just be able to take out more particles before it clogs up. A dual filter like a Filter Boss only allows fast changeover to a clean filter. Both of these only are dealing with solids type of problems in your tank (in the long run it is just a bandaid and you need to clean the tank).

But yes if you have a lot of sludge in you oil sump, and you can keep it suspended, then you could filter it. But if you have a lot of sludge in your oil pan you have a much larger issue.

**skipmac** · 13-09-2011, 06:24

Quote:

Originally Posted by Don Lucas

Is there really any benefit to these systems?

They mostly are just removing particles by providing finer filtration. But particles aren't the real problem for most systems it's the contamination of the oil from by-products and these aren't going to be effected by better filtration.

I first heard about this idea years ago but figured change your oil on time and you don't need it. Plus if they were that good how come engine manufacturers didn't require them.

Then I found mention in Nigel Calder's book. According to his data, standard oil filters only work to about 30 microns but the greatest wear and damage to the engine comes from particles in the 10-20 micron range. A bypass filter system will filter down to 1 micron.

It wasn't that expensive and it added the advantage of a remote, easily accessible filter to make the oil change much easier. So even if the secondary, bypass filter doesn't do that much, it does keep me from dumping oil in the bilge every time I change it.

sdowney717 · 13-09-2011, 06:34

bypass filters are a good idea as those dusty silica fines wear away metal, think sandpapering polishing.
BUT, these are more worthwhile in road vehicles where there is more road dust in the air.

CharlesFCook · 13-09-2011, 06:38

This is kind of neat....

Dieselcraft centrifuge

**David M** · 13-09-2011, 06:41

Keep in mid that oil needs to be changed anyway because the additives break down over time and the lubricity of the oil itself breaks down over time. No amount of filtering will change this fact.

I think a bypass system adds unnecessary complexity. It is probably better just to change your oil more frequently.

Randal Johnson · 13-09-2011, 07:39

In 2007 I installed an oil polisher on my main 4045T John Deere and on my Northern Lights 9KW gen-set. I used two Gulf Coast Filters I purchased new on Ebay. They were army surplus. I incorporated a 27 gallon new oil tank and a Reverso pump with a valve manifold that would allow me to change the oil in either engine sump or filter separately.
My main engine holds 14 quarts of oil and the GCF housing holds six quarts. I change the filter and the six quarts of oil every 150 hours and send samples to Lubriport Labs, Inc. All reports have been good.
The oil pressure typically drops about five pounds as the result of pumping a small amount through the filter while the engine is running. I know this is controversial but I pump the used oil into one of my six fuel tanks. It is diluted and filtered several times before being burned in the engine.
Below is a link to some pictures of the installation at the Diesel Duck discussion link.
Oil change/polishing system on Dora Mac - Photo Album

Chief Engineer · 13-09-2011, 07:39

Cost of Oil Polisher $$$$$$$$$$$$$$$$$$$

Cost of Oil and Filter$$

**skipmac** · 13-09-2011, 07:44

Quote:

Originally Posted by David M

Keep in mid that oil needs to be changed anyway because the additives break down over time and the lubricity of the oil itself breaks down over time. No amount of filtering will change this fact.

I think a bypass system adds unnecessary complexity. It is probably better just to change your oil more frequently.

Agree it does add a couple of more hoses, fittings and places to leak. However, the built in filter on my engine is in the far back of the engine, under the block and the intake manifold, air cleaner, injector pump, fuel lift pump and more, AND the existing filter is horizontal, guaranteeing you spill oil into the bilge when you change it. For me, the bypass system is worth it just for the easy access I get to the filters for oil changes.

**Jim Cate** · 13-09-2011, 07:47

How many cruising boat diesels die due to wear from oil that is only filtered by the normal manufacturer's systems?

I think that this is a non-problem for auxilary diesel engines that are maintained to the OEM's standards. I certainly have better things to do with my money and engine foom space.

Cheers,

Jim