What is this in the oil system?

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Airnet

Member
Joined
Nov 13, 2020
Messages
24
Vessel Name
Valhalla
Vessel Make
West Bay
It's my first oil change on this boat. Anyone know what this is? I know it's part of the oil system. It measures oil flow. I have a guess but it's only a guess.

Thanks
 

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Yeah, that is an external oil filter made by Puradyn. I have 4 of them on my boat. 1 for each main engine and 1 for each of my 2 generators. Consider yourself lucky you have them. These really help to extend the life of our oil and the filtering of your oil.
 
T
What engines and how long between changes?
 
Interesting paper from Chevron lubricants on TBN and how it has changed with modern engines.

What causes engine oil to lose lubricity? My understanding is the oil just wears-out, and the best indicator is acidity via TBN (and now "TAN" per above article). Of course contamination is important, and perhaps 50-years ago sludge was a problem that could overwhelm OEM filters. Still a problem that needs an off-engine filter with fittings? Will a bypass filter abate degredation of TBN readings?

I can understand that for difficult-to-access OEM filters, a bypass filter in a convenient location makes sense. But I don't understand how it could extend the life of oil in a normal/healthy engine. What am I missing?

Peter
 
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My understanding is that the Puradyne filters are much finer than the main filter. Because of the back pressure that the full flow would cause, the Puradyne filter is plumbed as a "bypass" filter (in parallel with the oil circuit). In the long term the smaller particles that can pass through the main filter are removed by the Puradyne filter.

Bottom line: you would be filtering to a finer filtration level.

As the Puradyne literature says, oil change timing would be based on oil analysis results (and not, say, engine hours).
 
Centrifuges are great. Anything that reduces contaminants is a benefit. But you also should be doing routine oil sampling with a lab.
 
Bypass filters remove debris down to 1 micron, some filters even smaller. The normal filters remove debris to 30 microns. Bigger debris, more wear on lubricated parts.
There's dozens of studies on the internet. I've been using bypass filters or centrifuges since the 1960s on commercial and yacht engines. I usually get double the hours as most others running the same engines. I test my oil about once a year. I only change it if the report is bad. That's never happened.
 
From Blackstone Labs regarding bypass filtration, https://www.blackstone-labs.com/by-pass-oil-filtration/

Want to run your oil longer than you used to? Lots of people do. We take many factors into consideration when determining your optimal oil change. Many people think choosing the right oil is important, but in reality, you can run any API-certified oil indefinitely, as long as it’s not contaminated. That’s the real key: not contaminated, with metal, solids, moisture, or fuel. So what can you do to keep your oil in pristine condition? Enter bypass filtration.

In-line oil filtration — the oil filter that comes installed from the factory — filters oil entering the engine down to roughly 30–40 microns (millionths of a meter). This is about the most the in-line system can achieve, because when the oil is cold or the filter is partially plugged, a finer filter would cause too great a pressure drop, forcing open the filter bypass valve and allowing unfiltered oil to circulate through the engine.

Bypass filtration works differently. When this type of auxiliary system is installed, some of the oil bypasses the in-line filter system, flowing though a bypass filter and then returning to the oil sump. Using this method, sump oil is constantly being cleaned any time the engine is running, and it can be filtered down to a very fine size. All you have to do to maintain the system is occasionally change the bypass filter.

Bypass filtration systems remove blow-by and oxidation products from the oil and can help reduce silicon accumulations. Having a bypass filtration system installed increases the overall sump size of the engine, helping dilute the concentration of metals in the oil. Oil does not wear out. Its usefulness is limited only by contamination. Bypass filtration removes or dilutes many of those contaminants.
...
Later,
Dan
 
I would agree to the above with an exception.
That exception is the base oil mix loosing strength. That shows up in loss of viscosity. (Oil thins out)

Keeping the oil clean is very important. And far more important when tolerances are tight. However when the viscosity of the oil changes, it doesn't matter how clean the oil is, the oil will fail at it's first assignment. That is in protection of metal to metal contact.

A synthetic or synthetic blend oil is a stronger oil and can take longer oil chnage intervals. And in the end, all oil will fail and lose the original viscosity mix it was made. Before the oil reaches that point, a drain and refill is desired. Again no matter how clean that oil might be.
 
From Blackstone Labs regarding bypass filtration, https://www.blackstone-labs.com/by-pass-oil-filtration/

Later,
Dan
I'm confused. I totally get the contaminant discussion. But the deeper technical discussions reference TBN number (which is associated with acid remediation) as an indicator of when the oil has worn through its ability to do its job. T he bypass filter is designed to reduce particulate - what is the connection between acid and particulate? In other words, what about enhanced filtration changes the TBN number?

The Blackstone article says oil doesnt matter as long as its API compliant. Does that mean that all the specific engine manufacturer acceptance listing is a load of BS?

Seriously, I'm confused on this one.

Peter
 
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I'm confused. I totally get the contaminant discussion. But the deeper technical discussions reference TBN number (which is associated with acid remediation) as an indicator of when the oil has worn through its ability to do its job. T he bypass filter is designed to reduce particulate - what is the connection between acid and particulate? In other words, what about enhanced filtration changes the TBN number?

The Blackstone article says oil doesnt matter as long as its API compliant. Does that mean that all the specific engine manufacturer acceptance listing is a load of BS?

Seriously, I'm confused on this one.

Peter

My understanding is that the acid is created from the sulfur in diesel. Filter out the sulfur that gets into the oil from the diesel fuel, and the additives, measured by TBN, will have less work to do and last longer.

When Low Sulfur Diesel(LSD) was replaced by Ultra Low Sulfur Diesel(ULSD) the amount of the additive package, aka the TBN number, was lowered. Some of the oil I was using in the time of LSD had a TBN level in the high teens or low 20's. I believe the oil I am using now is around 10ish out of the jug/bucket.

My last oil sample, which had gone for 11,500 miles and was over three years old, had a TBN of 6.2. Samples going back to 2014, only a had two samples lower than 6.0. One was 5.0 and the 5.5 with 15,000 and 15,995 miles. Seems like I had one sample prior to 2014 that might have been lower than 5. Maybe. Usually, based on the wear numbers, TBN, other metrics, I have been changing out oil that still had life left. The manual say to change at 5,000 miles and I usually go to around 15,000.

My interpretation of Blackstone's statement was to use any API specified oil that meets the engine makers recommendations. The usual oil discussions are that Brand X oil is better than Brand Y. The oils I have used have been blessed by the engine manufacturer and I have used oil from John Deere, Shell, Delo, Mobile, and maybe one or two other brands, that had 0W40, 5W40, and 15W40 weights. Been doing used oil analysis on the 0W40 and 5W40 oils for well over a decade and never seen a difference in the reports. Those oils were from JD, Mobile, and Shell.

Decades ago, there was an oil brand that had a strong following but I would not use it because it was not API rated. People swore that the oil was great but I sure would not use it without the API rating.

Later,
Dan
 
We ran a puradyn bypasss filter on Volunteer and had good results. According to the puradyn info some of their filter media was actually embedded with some of the necessary additives that dissipate from oil over time. The oil was noticeably cleaner to the eye also. Mine had a internal heat coil to help cook off moisture.
HW
 
oil does not loose its viscosity, oil becomes contaminated, if its filtered well you could continue using it for a very long time. so that equipment , looks to me like an oil polisher.
 
^^^ I believe this to be correct for the base oil.

However most oil and all multi-viscosity oils have viscosity index improvers. (VI Improver) This is used to get the oil to be different grades and flow for different temperatures.

While the base oil it's self is still the same (baring any impurities) the VI Improver used in any given oil formulation will break down from heat and use. If the oil was filtered so ALL impurities were removed, the VI Improver used in the oil at some point will shear down and break apart. Then the oil no longer has the same viscosity charistics that it did when it was new.

A single weight oil (non-synthetic) will be far stronger and last longer than a multi-weight oil. This is because the single weight oil has less or no viscosity index improvers. It is not formulated to operate at two different temperatures.

With the use of synthetic oil blends, the whole oil blend thing changes because synthetic oil is stronger. (and more expensive) A synthetic blend is stronger than a non-synthetic and a fully synthetic is stronger than a synthetic blend. A stronger oil will last longer.
 
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