Oil Bypass Filters? And, the latest update

We are getting very close to the start of our big trip!


Roberta and I are on the final couple of weeks at our home in Mexico. At the end of this month we return to Seattle, where almost immediately we’ll run Sans Souci one hundred miles north for a serious shakedown. If we find any glitches this will give the mechanics a couple weeks to fix things before we start our run to Japan on April 23rd.


All of the work on the boat is suddenly moving faster than I could have imagined. Here’s the latest update from Jeff, the project manager:


LED lights : All led lights have been ordered, they are out of stock on some and they are shipping us everything they have. I should have the remainder in 3 weeks. This is OK , I can install all the dimmers and get things ready to just plug in. These are going to be really nice.

A/C : The A/C Units are up and running and I was running the Kabola heater today off the system. It worked well. Brett is coming tomorrow to finish up last details and really run the system check for leaks. I am going to run the system and test through the month.

Electronics: The new Furuno Navnet 3-D system is awesome

• Network and Internet: Ed is now really making the network work and make it work properly. The M-7 should be up and running tomorrow. The video card is in and all monitors are working and things are really taking shape. All Simon parts are ordered and things are getting wrapped up.

Lazarette : Starting tomorrow we start installing the rest of the equipment. ( Dive compressor , relocate the water maker.)

Generator: The new Generator is up and running and carrying a load. We ran both A/C units on it and on the A/C panel we are drawing around 36 to 38 amps (including the air handlers). […] The generator did not even seem to struggle. I cannot believe how quiet it is. There still is no sound shield and you don’t really notice it running. 

Atlas Remote: The new atlas remote is pretty cool with a picture of the boat on it.





I think I’ve discussed all these projects before, so there isn’t much to add. The Atlas control panel is the panel for controlling my international shore power converter. We’re installing it on the main electric panel. Currently, for me to check on the shore power I’ve had to lie on the floor of the lazarette, which gets old after a while.


To me, the most noteworthy thing is that I was just in Seattle a couple of weeks ago, and the boat was sitting out of the water, with everything so taken apart it was hard to imagine that things would ever come together. Jeff was very confident that all would come together, and as predicted, we have the finish line in site (or, is it just the beginning?)


There is one project which has been a bit controversial.


The owner of the second Nordhavn 68 installed a “Bypass Oil Filtration System” from Puradyne. This system supplements the existing oil filtration system, extending the life of engine oil.

Typically, this is done on main engines, but in my case, I’ve considered it for my 20kw generator.


The primary benefit for me is that it allows me to extend the life of my engine oil. The puradyne site claims that I might be able to save on “new” oil by as much as 90%. I did some back of the envelope math, and my estimate is 17 oil changes, just for the generators, between Seattle and Japan. Oil is bulky and hard to dispose of. Anything that reduces the amount of oil I need to lug around is a good thing.




Here’s some pictures from the second N68’s installation of the system:



Filter housing looking aft
oil filter mounted on starboard DD60 series




Filter housing looking forward

Bypass oil filter mounted on starboard DD60 series




Bottom of filter – electrical and piping

Electrical connections, drain, vent and heater closeup



Bypass filter gravity drain connection

Gravity drain connection “t” at oil pan – tied to pan drain


Unfortunately, whereas Detroit Diesel blessed the installation of this system on my friend’s boat, Lugger expressed concerns about installation on my boat. Here’s their response to Jeff’s query:






Our supply of engines for the Nordhavn vessels, are based upon the John Deere Industrial engines, and because they are basically tractor engines and used differently from a road tractor, constant rpm use is part of the design requirement, for plowing, digging, harvesting, driving lots of hydraulic pumps and pto drives, whereas the MTU Series 60 engine was designed as a variable speed engine. Running a Deere based engine at a constant rpm is right up it’s design spec, although at rpms that operate fuel systems, oil systems at designed pressures, piston speeds that evenly heat, cooling functions that evenly cool the iron mass, and etc. We like the constant 1200 to 1800 rpm operations, because all of the vital functions are operated at their designed levels, allowing the engines to last for very long periods, when maintained according to our recommendations.


That does not mean, extended oil change intervals, or coolant change extended intervals, or extending the life of filters. I would suggest, and this was recommended by Bob Senter, our trainer for some of the Lugger engine owners, that they visit a web-site: http://www.noria.com/learning_center/category_article.asp? articleid=311&relatedbookgroup=Lubrication


Remember, not all manufactures use the same additive combinations in their recommended oils, and today’s oils generally contain more dispersants than ever before, to carry the high levels of soot created under emission requirements. Filter changes become more important than ever before, even though visual observations may indicate less need. Where does it all accumulate if not in the filter, in the low pressure areas within the engine, and despite the convenience of having less waste oil to dispose of, chances are that rebuilds occur more frequently, and remember, that’s long after the warranty has expired, or blame can be attributed, or the original owner has gone land cruising.






Lugger may not be completely understanding the Puradyne system and how it works, but I am not so passionate about installing the filter bypass system that I want to push the point. I constantly have to remind myself that anything I install on the boat must be maintained, and I’d like to reduce, NOT increase, the amount of maintenance I need to do.


And, somewhat related to the topic of keeping things simple, I received an email, in response to my last blog posting about power management, which I thought everyone might enjoy. It’s from Bill H, a commercial fisherman in the Bering Sea, who will be aboard Sans Souci during our upcoming voyage.




Hi Ken. I was reading your electrical entry in your blog. I don’t have near as much issue with electrical things as you do.


I have a Mer Equipment Co (Seattle) 20kw generator. The engine is an Isuzu C240 it burns 1-2 gallons an hour. This generator runs non-stop often for

2-3 months at a time. When I leave town for out west it runs constantly. I just rebuilt the generator engine last year for the second time. First rebuild was at 34,000 hours and the second at 36,000 hours. I never concern myself with generator load. Sometimes it’s just keeping my coffeepot warm. I have electric 2 burner range, electric heaters, three 1000 watt sodium lights for seeing at night when I want to, half a dozen double 3 foot fluorescents on deck, a couple 500 watt decklights and various small draw items. There are also some 240 volt 3 phase pumps which I use when needed.

One is a 2 HP 1 1/2 inch for the bilge, the other a 10 HP 5 inch pump for the fish hold which can be tanked.


It will also valve to the bilge if needed. I have heard lots of opinions about “load” but with up to 36,000 hours between rebuilds I’m sticking with what works for me. There’s always 3 ways to do things; the right way, the wrong way and my way, so I don’t recommend any of my procedures to anyone.


Lately I have been averaging 6.3 gallons an hour with main and generator running. This is directly proportional to how far you push the throttles towards the windshield. At WOT (wide open throttle), which is about 1775 rpms on my D343 Caterpillar it burns 11.5 gph.


At 1620 the burn is 9.5

At 1500 the burn is 8.4

At 1410 the burn is 7.5

At 1310 the burn is 6.3


The throttle setting is also directly proportional to how much fish I have in the hold. Sometimes you don’t care about expenses when you have a nice load to offset it. More often than not I err on the side of economy regardless. As far as speed goes, the difference between throttle settings is in 10ths of a knot so where’s the fire? Wide Open Throttle is still available if you need it.


So there’s another 2 cents worth. You must be up to almost a half a buck by now. Best regards. Bill




Reading Bill’s email has me thinking about whether or not my boat is more complex than it needs to be.


Before I comment though, I’ll share a second email from Bill. I asked him whether or not he has a second generator as backup.




Hi Ken. As for redundancy; I do have a 7KW hydraulic genset that runs off one of the hydraulic pumps on the main engine. I never use it unless my main generator quits, which is a rare occurrence, but has happened exactly twice since 1985; once on the way back to Adak from Attu. I also have a very small inverter that can run some of my stuff for a short time only. Many boats my size have 2 gensets and any boats larger certainly will have. There are also some boats I know, which operate all the way to Attu, who run on 12/24/32 volts DC only. You must also realize that our mission is pretty industrial and creature comforts are secondary at best. […] I’d like to put a disclaimer on a lot of the stuff I say such as: “Don’t try this at home. Offer void where prohibited, certain restrictions apply, some equipment shown is optional, quantities limited while supplies last, you must be present to win, if conditions persist consult your physician. Best regards.





I always enjoy Bill’s emails. In addition to his great sense of humor, I’ve always been curious about how the commercial fisherman, who run some of the roughest seas in the world, have outfitted their boats.


After reading his email, I thought for a minute about why my boat is so complicated in comparison to his, and I didn’t have to think long. Bill’s boat does not have air conditioning, it does not have an international power converter (Atlas System), etc. I haven’t asked, but I seriously doubt it has a hot tub. His boat is perfect for its’ purpose, just as I hope mine is perfect for ours.


Nordhavn would be perfectly happy to deliver a boat without all the extras that Roberta and I loaded onto our boat. Each owner decides what gadgetry they want on their boat, and makes the decision based on their desires, and willingness to pay for, and maintain, whatever they buy.


Our boat is outfitted to be a “portable home”. There are plenty of people who have circumnavigated in small sail boats, and we could certainly do that, but given our choice as to the level of comfort we would like, we chose to be as comfortable as possible.


So… the bottom line is: Yes. My boat does have a fairly complex electrical system, but it is designed to provide plenty of power, whether at sea, or in port, in virtually any country around the world. And, to be fair, I’ve really made it all sound far more complex than it really is. As I said in my last blog entry, power management becomes second nature after a bit of time living on a boat. It’s not something we spend a lot of time thinking about (except when writing my blog, of course!).


17 Responses

  1. Ken:
    Those electric oil refiners have been around since the early 80’s that I know of that company used to be called Purifiner. They were popular for a while then kind of died out. The biggest problem with them still exist. All that extra weight hanging on the oil drain plug threads that were not designed for that purpose, in combination with the vibration of a diesel and you have a failure just waiting to happen. I belive in the old addage that oil is cheaper than bearings and would rather change the oil more often and be assured that the additive package is up to snuff. On a different topic your instant start generator should have a water jacket, heater so that the engine is already warmed up when it starts at it’s rated RPM under load. If the engine is cold you will cause considerable wear to the engine every time it starts. The reason your commercial fisherman friends gererators run so long between overhauls is because he never turns them off!

  2. Ken, thanks. Your answer about the fixtures was amusing. I’ll ask the sales guy about the difference. Regarding cool vs. warm, I’ve used both and do not like the quality of the cool white light, so warm for indoor use makes sense.

  3. Adam: The quick answer to your question is “I don’t know”. I delegated all of this to Jeff, who worked it out with the salesman at Imtra. Feel free to contact the salesman directly, at:

    Derek Stern
    30 Samuel Barnet Blvd. New Bedford, Massachusetts 02745

    I did order, before leaving the boat, one of the replacement bulbs. I never got around to installing it. My guess is that there is some marginal reason why it was better to replace the whole fixtures, but that the primary reason is that by talking me into the complete new fixtures, as opposed to just bulb replacement, the commission was substantially higher for the salesman. That said, I am a cynic, so ignore what I just said, and ask the salesman directly.

    As to the “cool” versus “warm” lights, my understanding is that the warm lights are interior, and the cool lights are exterior — and, that there is really no difference other than the look of the color. I haven’t seen the lights yet, so I can’t really say whether or not there really is a difference.

    Good luck!

    -Ken W

  4. Ken, a few more questions about the LEDs you selected: 1) How did you know how many you would need? I don’t see equivalent halogen wattages on all of the product pages; 2) Why did you pick some cool white and some warm white? 3) Why did you replace your old fixtures rather than using drop-in replacement bulbs like these: http://tinyurl.com/ledbulbs (http://tinyurl.com/ledbulbs) ?

    Thanks again for your willingness to put all your hard-won knowledge online!


  5. Sam: I did some googling and couldn’t find anything about synthetic oils in Luggers. My guess is that Lugger would frown on it, but I don’t know.

    Here’s something interesting and educational I found while doing research.

    http://www.kensblog.com/upl (http://www.kensblog.com/uploads/16765/2009_03_08_n63/luggerclassnotes.pdf)

    It’s an excerpt from my hand written notes, while attending a class on Lugger diesel engines and generators. My note taking isn’t great, so no promises on accuracy or completeness.

    -Ken W

  6. Adam: Here’s more information that you could possibly want.

    My boat requires:

    – 43 of these: http://tinyurl.com/clm68d (http://tinyurl.com/clm68d)
    – 66 of these: http://tinyurl.com/dk2xfw (http://tinyurl.com/dk2xfw)
    – 33 of these: http://tinyurl.com/cnkxz9 (http://tinyurl.com/cnkxz9)
    – 14 of these: http://tinyurl.com/aqk2cc (http://tinyurl.com/aqk2cc)
    – 12 of these: http://tinyurl.com/c5jgty (http://tinyurl.com/c5jgty)
    – And, four new dimmers: http://tinyurl.com/bpz4db (http://tinyurl.com/bpz4db)

    -Ken W

  7. Ken,

    Just out of curiosity, do you run synthetic oil in your engines? Does Lugger have an opinion on synthetic oil? I ask because several of my cars run synthetic and go up to 15,000 miles between oil changes at the manufacturers suggestion. I checked on the trip computer of one of them and it reported an average speed of 29 miles per hour. That’s over 500 hours between oil changes, and I’d think that the frequent starts and stops and varying RPM’s of a car engine would be a lot tougher on oil than constant running.

    Of course, it’s a whole lot more expensive to repair or replace the diesels in your boat than the engine in a car. But it’s one more thing to look into…


  8. Ken, what LED lights are you using? Are they direct bulb replacements for (I assume) a 24V halogen system, or did you have to put in new power supplies? Thanks! /adam

  9. Ken – Although I have not been boating now for 13 years, I seem to remember being able to add small amounts of used engine oil to the fuel tanks and burning it in the engines. A couple of advantages are increased range and fuel economy and a neat way of getting rid of used oil. If you have a fuel polishing system which I imagine that you do, it might be a way to go. Might be worth checking into.

  10. Looks like Bill will be both a knowledgeable and entertaining member of the crew! You are lucky to have him along.

    Believe it or not, my little Willard W40 has Puradyn oil filters on both the main engine and the generator. I have not paid much attention to them but note that mine are much bigger and blacker than the units installed on the DD/MTU’s. Both installations have heating elements to assist in the removal of water from the oil. I had occasion to call Puradyn and am happy to say that the head of technical support was a delight and he offered to guide me through a modification to the main engines filter installation by staying on the phone with me until it was done. Several years before, Balmar did the same thing on a misbehaving alternator regulator. Credit where it is due.

    I understand Lugger’s position, but I have observed oil processed by a Gulf Coast filter looking new in a car after having been run 8000 miles. With Gulf Coast depth filters (using Scott or Bounty paper towel filters) when you change the roll of paper, you have to add one or two quarts of new oil to the filter (depending upon size) and it is argued that you have replaced any depleted additives when this is done. Gulf Coast filters remove sub-micron carbon black from the oil. These filters in giant size are used on oil rig Bessemer multi-fuel engines as well as remote oil pumping stations and by crew boats in the Gulf (naturally). There are war stories about these filters preventing engine failure owing to contaminated fuel. They go before the Racor filters.

    Ships use Puradyn filters, but they do not use engine like the new Luggers. So, I know that the Gulf Coast fuel filters are an excellent first line of defense for contaminated fuel – which you may get as you travel to exotic ports; but perhaps the new engines might not benefit as much from oil filters. The funny thing is that conventional oil filters don’t remove the additives because they don’t do that good a job! Cummins used to brag that their branded filters were impregnated with a proprietary additive to better protect their engines. It would be very interesting to know if any vessels in the Bering Sea fishery use either Gulf Coast fuel filters or any bypass oil filters as do the Gulf crew boats. BTW, the Air Force uses these filters on their equipment in Alaska.


  11. You use to be able to burn waste oil in space heaters. Pitty your boiler can’t use it. But then again once you go south I would guess your need for heat will be very small.

  12. Jack: I am installing the Bauer Junior II. The hookah will stay on board, and will get plenty of use. The hookah works great for most uses, and is fun for our guests to play with when learning to dive. It also gets regular use when the bottom is cleaned. The compressor is for when I want to take the tender somewhere to dive. I thought about just getting a portable hookah system that I could carry around with the tender, but decided that tanks are the most flexible solution. – Ken W

  13. Hi Ken:

    I just wanted to ask what type of dive compressor you chose to install? I would also be interested to learn the reason you chose the model that you did. Are you disposing of the hookah rig, or will you keep that as well. Thanks.


  14. Sam: People do burn old oil (in small ratios to diesel fuel), but I’ve never really checked on it. Even if recommended, I doubt I’d ever be able to talk myself into it. The problem is that old oil is pretty grungy. I have to believe it would shorten the life of the fuel filters, and changing fuel filters is one of my least favorite tasks on the boat. It should be easy, but there are too many opportunities to suck air into the engine, meaning I have to re-prime the system, which can be a nightmare. Maybe I’m misunderstanding the process somehow… – Ken W

  15. I’m no expert on diesel engines, but I’ve heard that people often mix their old engine oil in with their diesel and burn it. My guess is that this cannot be done on the new electronically controlled engines, but if you haven’t checked into it you may want to.


  16. Chuck: My boat does indeed have a “new”, and an “old” oil storage tank. Each is around 70 gallons, which goes faster than you might think. I have two main engines which each consume 11 gallons of oil, plus two generators, all of which need an oil change every 200 hours of operating time.

    I always grumble when I put oil into the “used” tank, because I know it will be a pain getting it out. Few fuel stations are set up to suck out oil from my tank. I have to pump it into five gallon buckets and lug them up the dock.

    Nordhavn makes it exceptionally easy to do oil changes. For the most part, I never see the oil, and it is mostly just pressing buttons. The toughest part is really just carrying and disposing of all the oil (and used filters).

    -Ken W

  17. I am quite surprised Nordhavn did not equip you boat with tankage for lube and waste oil. I know your space is tight, but I believe most manufacturers of vessels your size and larger have designed this into their vessels. I wonder if the larger Nordhavn’s have tankage?

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