Bypass filtration report

Recently, I requested comments on another site seeking opinions on bypass filtration for diesels.* Not surprisingly, there were many opinions ranging from "change your oil every 50 hours and forget about it" to suggestions to check out spin filters from 2 different manufacturers.* While the spin filters look like a good alternative, I elected to install a Puradyn filter that should remove contaminants down to 1 micron.* I wanted to pass on observations so far.

The rationale for installing bypass filtration in the first place was to remove carbon from the oil, reducing the potential for wear and general anal compulsiveness over engine longevity.* I am not particularly interested in extending the interval between oil changes, since the cost of oil seems pretty minor compared to the cost of repairs.* I guess I just like the idea of clean oil.

The Puradyn unit has two attributes not common to others.* First, the filters can be purchased with a slow release additive package that supposedly keeps the additives at appropriate levels over an extended oil change interval.* Second, the unit has a heater element that cooks the oil and allegedly removes volatiles like water and diesel fuel from the lubricant, if present.* Since I am not interested in extending the interval between changes, the additive package is not important, so I have opted for the simpler, less expensive ($15.00) filters without the additives.

I am undecided on the heater element feature.* As oil runs through the bypass filter at a rate of around 6 gallons per hour, the heater element condenses around 1/8th of a cup of oil per hour of running that discharges out a drip tube.* I intend to have this discharged oil analyzed for contaminants and will report on that in the future, so for now I can't tell if this feature is worthwhile or not.* If the oil sample comes back showing excessive contaminants, water or diesel, it is worth it.* If not, then I will disconnect the heater element.

What I can say is that the more hours I put on, the cleaner the oil becomes.* After a typical oil change, my CAT's oil* would normally be pretty black.* Not anymore.*

Whether this piece of equipment is worth others installing may be a matter of how compulsive you are to have clean oil.* Since the tolerances of the average diesel are greater than the size particle filtered out by these systems, longevity is probably extended.

Below are a couple of pictures showing the mounting of the unit - it is large - and the plumbing of the supply line for the oil from the block.

Hi Delfin - this looks really interesting. I've just found a supplier in the uk which is only 2 miles fropm where I live!

If I can find space to fit these to my Cummins C450 engines, then I have a feeling they'll soon be fitted.

Many thanks for the post.

Yes, the unit is large, but that is because the filter is huge, presumably having a lot of capacity to absorb contaminants.* Mine fit nicely on top of the trannie on the L bracket I fabricated that you can see in the picture.* Just make sure you get the highest grade hose for the supply and return - use high pressure, high temperature even though it is low pressure (more robust).* Also, before you buy, identify where you will take the supply from and where the return will be plumbed.* On my CAT, there were plugs in the oil galley that could easily be removed and tapped for supply.* Previously, I removed the drain plug and took it to a machine shop where I had it drilled out and a street ell welded on allowing me to plumb to a pump for draining oil.* I just plumbed the return from the Puradyn to downstream from the shutoff valve I screwed onto the street ell.* Seems to work well.

Delphin that looks like a nice setup and great access to the engine. What is the clear plastic bottle with the tubing running to it? Looks kind of the bottle I use to catch the blowby oil mist on my Cummins.
Steve W

The oil passes through a heater which allegedly removes volatiles like diesel and water from the oil. It flows out this tube into the container you see in the picture. I am suspicious about this particular feature so my intent is to send this for analysis to see if it has any contaminants. The rate of discarge seems to be about a half cup every 10 hours of operation. If the oil analysis of this doesn't show contaminants I'll just pull the fuse. If it does then this is a nice feature providing additional cleaning of the oil. Puradyn is the only bypass filter I know with this particular feature.

Delfin wrote:

The oil passes through a heater which allegedly removes volatiles like diesel and water from the oil.

*

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*Considering that the* boiling point of diesel fuel is around 370* F*and up I would not expect much benefit to anyone other than the guy who sells you lube oil.

We'll see once I test it. Like I said, I am suspicious.* However, the point of the heater is not to boil the oil, but water and diesel fuel, which boil at 212 and 175 degrees respectively.


-- Edited by Delfin on Tuesday 26th of January 2010 02:27:57 PM

Delfin wrote:

We'll see once I test it. Like I said, I am suspicious.* However, the point of the heater is not to boil the oil, but water and diesel fuel, which boil at 212 and 175 degrees respectively.

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You might want to check your F to C conversions.

*

Delfin:* Assuming a "good" leisure rated engine with regular oil and filter changes, the chances of engine failure due to inadequate lubrication are virtually nil. So why mess around with a system that adds external tubes, hoses and fittings that could fail and cause a lubrication failure?

Sunchaser, to have cleaner oil would be one possible answer.

-- Edited by Delfin on Tuesday 26th of January 2010 09:08:21 PM

RickB, right you are on the vapor point of diesel.* It is around 350 F/175 C, and I mixed Celsius with Farenheit on the water/diesel comparison.* One correction though, the vapor point on synthetic lube oil, which I use, is 450 degrees F, not 370.* Whatever, an oil test will tell whether the vaporized product has contaminants or not.*

I remain somewhat perplexed on the perspective of some that cleaner oil, where contaminants less than the machine tolerances of the engine are removed, is not a worthwhile objective, especially with the relative cost differential of repair versus maintenance.* Few people drop dead, yet most people carry life insurance.* Few engines fail from problems with lubrication contaminants, but for $15 more per oil change, isn't bypass filtration reasonable life insurance for an engine?* Apparently some do not think so, which is a.o.k. with me, although they seem to strain to make their point.

-- Edited by Delfin on Tuesday 26th of January 2010 09:09:16 PM

Delfin:

I work* with diesels of all shapes and sizes. The current biggest is 4000 HP. The yellow engines, Cat, like you have, are industry leaders*when it comes to designing filtration and lubrication systems. Cat offers superlative warranties on engines and components based upon*their knowledge and*experience. They put their money on the line with their designs and recommendations. I note you use synthetic oil. Cat does not see any benefits to that over their recommended oils. And to assume that your bypass filtration system is an improvement over what Cat* designed assumes that you know more than the Cat engineers. Since I work with Cat engineers and maintenance personnel, I have grown to trust their abilities and judgement. Cat however does not do my dental work, I go to a pro for that.

If diesel engine technology was new and the industry was still at the bottom end of the learning curve, I could see where setting up a system to remove even the minutest traces of contaminants in the lube oil would be a smart thing to do.* After all, like the tiles on the Space Shuttle, there would still be unknowns about what might affect reliability and longevity.

However, diesel technology is not new.* It has a long and impressive track record of use in everything from railroad locomotives to ships to cars to industrial equipment, you name it.* Millions of*diesel engines*have been torn down, examined, and overhauled or rebuilt.* The effects of*dirty fuel, ancient fuel, filthy lubricants, sand in the crankcase,*and so on, are all well known.* *And considering some of the appalling conditions under which we've probably all seen diesel engines work and continue to work, my guess is that traces of diesel fuel and water that might get into the lube oil are going to have no significant impact--- if any impact--- on the longevity of the engine.

If an engine is getting so much fuel and water into the lube oil that a device to vaporize it off is warranted, it would seem to me that this particular engine has a serious problem.* Vaporizing off the diesel and water would only be curing the symptom, not the cause.

If diesel and water ingress in a diesel engine's lube oil is a common problem to diesel engines in general, and one that reduces the engine's reliability and longevity, it would seem to me that it would be in the interests of Cat, Deere, Cummins, MAN, etc. to make such a device a stock accessory for every diesel they sold.* Do they?* (I don't know, I'm just asking the question.) Diesel engines have certainly been around long enough to know if this is a real, or significant problem or not.

Sunchaser's points in the previous post are well taken.* Warranty work is expensive for manufacturers because they foot the bill.* And unlike cars, bulldozers, railroad locomotives, cranes, oil rig equipment, etc. are not consumer items.* The people and companies*who buy these things are not*intending to "trade up" every few years.**They expect to get ten, fifteen, twenty, or more years of service out of them.* So if vaporizing off*traces of fuel and water from lube oil was a way to give their customers a longer service life, that becomes a competitive advantage and*I would expect the engine manufacturers to incorporate this feature into their engine designs from the outset.

It is hard not to think of things like this as "armchair hardware," devices that in theory will solve a problem, real or perceived.* Sort of like the magnetic fuel conditioners, although this vaporizing device would seem to have more potential to actually do something than the magnets.* But whether that something actually needs to be done seems very questionable in this case.

But, like the magnets, I can't see that having it in the system will hurt anything.* So it will be interesting to hear what Delfin discovers.

"...where contaminants less than the machine tolerances of the engine are removed..." is an interesting statement.* I'm no mechanic or engine designer or lubrication engineer.* But logic would seem to indicate that if*a contaminant is*smaller than the machine tolerances of the engine, then it*isn't a contaminant.* Or do I have that wrong......?


-- Edited by Marin on Tuesday 26th of January 2010 10:44:21 PM

Delfin wrote:

RickB, right you are on the vapor point of diesel.*

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I don't know what you mean by "vapor point" but I do know that the boiling point of diesel and lube oil covers a very wide range because those compounds are made up of a very wide range of components. The figure I gave for boiling point is the lowest temperature, the point at which about 1 percent of the stuff will boil away, to boil it all away will require a temperature high enough to destroy your oil, your engine, and everything else in the engine room.

You cannot "boil" diesel fuel out of lube oil and undo the damage. And yes, fuel contamination of lube oil in very small amounts is related to engine damage. Most of the damage is done by the mechanism that allows the diesel to get into the oil and the dilution is more a symptom than a disease. Wiping the blood off does not repair the wound.


-- Edited by RickB on Wednesday 27th of January 2010 06:23:09 AM

-- Edited by RickB on Wednesday 27th of January 2010 06:23:59 AM

Delfin:

On your oil filtering setup, I note several hoses, some problematic in my opinion. Five years ago my brother's "big" steel vessel suffered a lubrication failure on one of its engines. A contractor was working on the ER fire supression system and inadvertently moved/disengaged an engine oil drain line near the sump. Shortly thereafter, the vessel was underway with all the starboard engine oil draining into the bilge (that is another story) in a matter of minutes. Oil flow and pressure readings worked as they should have to alert Captain and engineer but it was too late and engine was toast. The insurers had a field day citing all sorts of reasons they should not pay for improperly designed plumbing and the engine manufacturer said not our design.

-- Edited by sunchaser on Wednesday 27th of January 2010 08:58:46 AM

-- Edited by sunchaser on Wednesday 27th of January 2010 08:59:22 AM

So why mess around with a system that adds external tubes, hoses and fittings that could fail and cause a lubrication failure?

Clean oil is of course going to wear the engine less than grit.

A big filter like this will do the job , but the spinner setup is smaller and perhaps easier to find room for. http://www.spinnerii.com/index.cfm/lev1/401/pressID/561/startrow/1

The spinner does have to be cleaned on occasion.

The folks wanting to extend the service life of oil are usually using very expensive synthetic oil, where 10 gal a fill gets pri$y.

Thanks Sunchaser.* It was actually the CAT maintenance manager and his field guy who thought bypass filtration made sense for a 3306 turning slow and inevitably building up more carbon.* They were indifferent about the type, but I think you might be hard pressed to find someone who thinks that reducing particulates from 10 microns to 1 micron has zero value, although your point about external hoses for supply and return being a failure point certainly is valid.*

Regarding synthetic oil for CAT engines, while I suppose they would like you to buy their oil, they don't care what you use as long as it meets their specs.* They don't seem to object to synthetic oil, since they sell their own, designed for the 3116 and 3126 engines I believe which have had quite a few problems in the field.

Like you, I prefer to go to the pros, and in this case when I asked the pro if it were his engine, would he install a bypass filter.* Since his answer was yes, it seemed worth listening to.

-- Edited by Delfin on Wednesday 27th of January 2010 10:06:08 AM

I recollect hearing stories yrs ago from truckies here in Oz, who made up their own bypass filter arrangements in the days before they were available ex-factory and used toilet paper rolls as the filter.* If I remember correctly, they managed to clean the oil so well this way, some got literally hundreds of thousands of miles between changes - in fact some never changed the oil, so it was claimd - just topped it up to compensate for unavoidable loss and engine consumption.* I never knew where truth ended and legend began, but I can see how it could work......and if I had the money and energy and my engine was newer.......

PB

Bypass filtration for oil makes sense if you're cruising all the time. As long as you keep it topped up, and test occasionally, it can be a godsend in reduced / eliminated oil changes and disposal of used oil. For the average boat with a couple of hundred hours or less a year, it's near useless. Now using that type of system to polish your fuel... that's a different story. The more you sit the more you need it, especially with large tanks.

Gulf Coast filters started with TP and paper towel rolls .

Far less risky to use a filter medium designed for the task.

The big trucks now use oil sampeling , 100,000 mi to 150,000 miles on synthetic is not uncommon.

Synthetic is claimed to reduce fuel burn a few % , makes sense when you run 1000s of gallons a year.

Marin, you wrote:

"...where contaminants less than the machine tolerances of the engine are removed..." is an interesting statement.* I'm no mechanic or engine designer or lubrication engineer.* But logic would seem to indicate that if*a contaminant is*smaller than the machine tolerances of the engine, then it*isn't a contaminant.* Or do I have that wrong......?

No, you don't have it wrong if you wish to define contaminant as a foreign substance that must be causing wear or harm.* If a contaminant is something that wasn't in the original product after manufacturing, like soot from incomplete combustion generated by a diesel operating at long distance cruising revs, then yes, I guess you are wrong.* If the machine tolerances of the crankshaft are 2 microns, and you remove particles down to 1 micron, you no longer have contaminants that cause wear, although you will still have contaminants that do not.* So take your pick on your own definition of the word 'contamninant,' but the point of fine filtration is to remove particles smaller than those that cause wear, hence my comment.

You also wrote:

"If diesel and water ingress in a diesel engine's lube oil is a common problem to diesel engines in general, and one that reduces the engine's reliability and longevity, it would seem to me that it would be in the interests of Cat, Deere, Cummins, MAN, etc. to make such a device a stock accessory for every diesel they sold.* Do they?* (I don't know, I'm just asking the question.) Diesel engines have certainly been around long enough to know if this is a real, or significant problem or not."

My understanding is that really large diesels frequently come standard with bypass filtration, as do some small gensets.* I am no expert either, but my understanding on why mid sized engines don't offer bypass filtration as a standard is that most are designed for applications where running at 75% power isn't the problem it is for trawlers.* At 75% or so power, soot contamination of the oil is minimized, especially with common rail, computer controlled injection systems, which the 3306 doesn't have.* I seem to have zero soot buildup in my genset which runs at 80% rpm, but lots in the CAT.* Does that mean the CAT has a problem?* No, it is just running at trawler rpms, so it has less efficient combustion resulting in more soot.* Does this mean the engine is too big for the boat?* No, it just means it is a trawler hull, where 40 hp is required to run at 7 knots and around 2.5 gph, but requires 240 hp to run at 9 knots burning 12 gph.* If this same engine were in an earthmover or truck, a full flow OEM filter would do fine, and the engine might wear out for reasons other than the fact that the OEM filter only takes out 10 micron and larger particles, although lots and lots of companies running mid-size diesels install bypass filtration to reduce wear and extend oil change intervals.* On Delfin, we run at more or less constant power all the time and would prefer fuel economy over kicking up a bigger wake.* Under those conditions, a full flow filter doesn't do the job a bypass filter does, but for 95% of the applications this CAT would find itself in, the OEM filter does just fine.

As I noted above, the Puradyn has a feature additional to the usual function of a bypass filter, which is a heater element the oil is subjected to, and that allegedly helps with the water and diesel contamination you mentioned.* The vapor you see coming out the crankcase ventilation is, I believe, at least partly water from the moisture contained in combustion air.* Whether this water vapor causes any problems or not I am skeptical of, but it is a normal contaminant.* As I also noted about the heater element, I have no clue whether this particular feature has value or not.* I would also venture to say that if someone argues that cleaner oil has no value on a diesel, they may be arguing for the sake of arguing.* It is true that installation requires external hoses, but then again, so does my MG 509 gear (for oil cooling), so that risk is probably manageable.* It is also true that changing the oil every 50 hours would help remove soot, but who wants to do that, and regardless, won't be as effective as filtering out virtually all contaminants every 60 minutes.

I have heard lots of arguments on why such units are unnecessary, but I haven't yet heard arguments that are particularly convincing for trawlers operating at trawler rpms.

-- Edited by Delfin on Friday 29th of January 2010 02:12:07 PM

Sunchaser, you wrote:

"Five years ago my brother's "big" steel vessel suffered a lubrication failure on one of its engines. A contractor was working on the ER fire supression system and inadvertently moved/disengaged an engine oil drain line near the sump."

That is really unfortunate, and I guess argues for not removing such lines before starting the engine.

Delfin, the important thing is you are confident your engine is protected from contaminated oil. However, after watching many*Cat 6 cylinder engines*over the years die due to poor head and cooler design and none due to lube failures, don't overlook those greater inherent weaknesses*

Delfin wrote:

Marin, you wrote:

"...where contaminants less than the machine tolerances of the engine are removed..." is an interesting statement.* I'm no mechanic or engine designer or lubrication engineer.* But logic would seem to indicate that if*a contaminant is*smaller than the machine tolerances of the engine, then it*isn't a contaminant.* Or do I have that wrong......?

No, you don't have it wrong if you wish to define contaminant as a foreign substance that must be causing wear or harm.

I would also venture to say that if someone argues that cleaner oil has no value on a diesel, they may be arguing for the sake of arguing.*

Click to expand...

Plus I suppose you can have chemical contaminants to the lube oil that no mechanical filter could remove, yet they could reduce the lubricating qualities of the oil.* This is the case with the Simms/Cav injection pump used on the old Ford Lehman 120.* This pump has its own oil sump and the oil in it can become diluted with diesel fuel that leaks down past the injection plungers, a leak that gets worse with time as the plungers and bore walls wear with use.* There is no cure for this--- wear can be held to a minimum by ensuring good lubricity in the diesel fuel since that's what lubricates the plungers in their bores--- hence the required 50-hour oil change for the pump.

And you're correct, I've never heard a mechanic--- automotive, aircraft, or marine-- say that clean oil is bad for an engine.

I just wonder, though, with an engine like he FL120 that supposedly can be a 12,000 to 14,000 hour engine in recreational use (they have gone over 25,000 hours between overhauls in constant use on ferryboats), all these hours racked up without the benefit of a diesel fuel/water "boil off" system for the lube oil or even a bypass-type oil filter, how much such a system would really add to the longevity of the engine.

These are engines that are supposed to be operated in the 1500 to 1800 rpm band, which in marine use is considerably below the theoretical loading figures you hear bandied about.* They achieve the proper temperature at these relatively low power settings and, assuming proper maintenance and service and little or no abuse, they seem to run "forever."

It's probably apples and oranges to compare the operating characteristics of an antique engine like the FL120 and a modern engine, so perhaps the need for additional contaminant removers is much greater with today's engines.

*

Marin,
A 3306 is not a modern engine.

True, but I suppose it depends on what you're comparing it to. The 3306 was introduced, I believe, in the 1970s and manufactured through the 1990s or so. Compared to some of the 1950s or earlier antique designs*still powering some boats, that's pretty modern.

But when I said "modern" in my post I was referring to the current generation of diesels.

-- Edited by Marin on Saturday 30th of January 2010 01:44:53 AM

current generation of diesels.

Is all turbo charged and includes high pressure rail + electronic injection.

3 or 4 little squirts per cylinder firing.

sunchaser wrote:

Delfin, the important thing is you are confident your engine is protected from contaminated oil. However, after watching many*Cat 6 cylinder engines*over the years die due to poor head and cooler design and none due to lube failures, don't overlook those greater inherent weaknesses

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LOL, thanks for the happy thoughts, Sunchaser.* Actually, CAT makes quite a few different engines, and I'm not sure you would find a lot of support for the idea that they all die from "poor head and cooler design."* The 3306 was designed for broad applications on the North Slope and I have personally seen individual engines with over 50,000 hours on them.* So perhaps I'll be lucky, remember to check the engine before starting it to make sure the bilge isn't full of oil, and go a few miles before poor head and cooler designs catch up with me.

*

Delfin - Look, you have a gorgeous boat and have done a ton of first class work to get it near perfect. I'm envious. Your zeal, enthusiasm and dedication is to be commended. Keep up the posts. Will you be on the Inside Passage this summer?

Sunchaser, I sure hope so.* I am trying to get retired so we can head to NZ and Oz, where we used to live.* That is probably still a couple of years away, but hopefully this summer we will get back up Alaska way, at least for a month or so.* Let's rendezvous in Ocean Falls, and debate the complexities of diesel management on a trawler!