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Filter Test Results

"Unauthorized test"? What would the response be to UL testing? Could go further point-by-point but why bother. Choice of such defensive defensive wording says a lot, at least to me.

To be fair, what are they able to respond to? They have none of the original test information/data/etc and would essentially be responding to posts on VAF. No one here has seen all the test information for that matter, only Dan's interpretation of it. That's great for us because he's established trust and respect within this community, but Heather & Co. don't know who he nor details about the tests which were done or even what lab did them. I don't blame them for not wanting to respond to that.

I agree the "unauthorized test" phraseology is pretty silly. And using that phraseology isn't a great look.
 
Me thinks they won't be selling their OEM'd "filters" much longer.
I'm not so sure about that. It's hard for me to believe that people actually thought a reusable filter would work as well as a traditional (disposable) filter. I think the people that bought Challenger filters had other motivations (e.g. saving money on oil changes). There will always be people trying to save a buck regardless of how it affects their engine. Just look at the unleaded fuel thread.
 
Ahhh - so you wish to denigrate the testing that was performed outside of your "authorized" control, but you also will not release the testing results of your own.

Got it.

I call BS.
BS is kind of strong language. How can you expect a manufacturer to respond to a summary of testing by some unknown lab. We see summary test results are being provided from this effort, but I do not understand why a full report of the testing methods, and results can not be published. This would include the lab doing the testing. Why are they unwilling to stand by their work? Why does any of this need to be confidential?

I am not saying any of the results are wrong, and the effort is much appreciated, and of interest. I propose, if you are going to ask a manufacture of a product to respond to these test results, a proper report is needed, with full disclosure of the methods used and lab that did the testing. Isn't that the only why to fairly ask them to prove it wrong with their own test data.

Respectfully...
 
BS is kind of strong language. How can you expect a manufacturer to respond to a summary of testing by some unknown lab. We see summary test results are being provided from this effort, but I do not understand why a full report of the testing methods, and results can not be published. This would include the lab doing the testing. Why are they unwilling to stand by their work? Why does any of this need to be confidential?

I am not saying any of the results are wrong, and the effort is much appreciated, and of interest. I propose, if you are going to ask a manufacture of a product to respond to these test results, a proper report is needed, with full disclosure of the methods used and lab that did the testing. Isn't that the only why to fairly ask them to prove it wrong with their own test data.

Respectfully...
I'm with airguy. If I'm protecting my product against an untruth, I counter with truth; in this case, in the form independent lab/testing data, etc.. It's not like there isn't a plethora of reputable testing labs and standards to test by. Maybe I reiterate the defined market the product is intended to compete in.

The "so says you" approach isn't helping the company's credibility.
 
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How can you expect a manufacturer to respond to a summary of testing by some unknown lab. We see summary test results are being provided from this effort, but I do not understand why a full report of the testing methods, and results can not be published. This would include the lab doing the testing. Why are they unwilling to stand by their work? Why does any of this need to be confidential?
See post 45
 
See post 45
I read it, and was the point of my post. May be my statement is more about the industry, and how it talks out of both sides...

Dan stated, "It was the price of working with a highly regarded lab."

I am just proposing, a reputable lab, should not be doing testing work contingent on confidentiality. It kind of questions the highly regarded part.

Having said all this, I have no experience in the field. I am just looking at it from the layperson perspective. Would a lab like Underwriters Laboratories require such confidentiality?

I do not recall reading how the test filters were provided to the lab. I assume they were all made anonymous and simply called something like filter 1 through n. That would be the only way to provide some form of anonymity. I understand that filter characteristics could be used to deduced the manufacturer, but as I am sure we all know, a blind-blind study is the gold standard.

The point being, if the lab is just testing a bunch of unknown filters, they have no horse in the race. They just need to back up their testing as accurate.

If they think a manufacturer is going to come back and say we don't like that you tested our filter for some outside entity, they can simply say they had no knowledge of the manufacturer for any of the filters tested.
 
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if you are going to ask a manufacture of a product to respond to these test results, a proper report is needed, with full disclosure of the methods used and lab that did the testing.
We didn't ask the manufacturer to respond. They obviously have a bias, the laboratory doing the testing does not. Data speaks much more authoritatively than marketing.

Secondary to that, the manufacturer did respond here - but not in support of their product with countering data, but rather to throw shade on the efforts of others finding facts. That type of response is guaranteed to peg my BS detector full scale.

Full disclosure - I bought one of their filters in June 2022 - I ran it for several oil changes (590 hours) - I am invested in the product and wanted it to work. It was proven not to work. I follow the data. If the manufacturer wishes to offer competing data, I'm listening.
 
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We didn't ask the manufacturer to respond. They obviously have a bias, the laboratory doing the testing does not. Data speaks much more authoritatively than marketing.

Secondary to that, the manufacturer did respond here - but not in support of their product with countering data, but rather to throw shade on the efforts of others finding facts. That type of response is guaranteed to peg my BS detector full scale.

Full disclosure - I bought one of their filters - I ran it for several oil changes - I am invested in the product and wanted it to work. It was proven not to work. I follow the data. If the manufacturer wishes to offer competing data, I'm listening.
I get it... I agree, I don't think they (manufacturer) are doing themselves any favors with the response they provided, but I don't think that discounts my pont.
 
See post 45
WE (those of us that fronted money for VAF oil filter tests) are one data point. OTHERS are free to pay for the same thing we paid for and repeat the tests. Their results will then either confirm that our data is valid or in question.

Just my opinion that a repeat test may not be exactly the same but would have similar results. The more that others are willing to pay to run the same test at a different time will create more confidence in the data our tests produced. Until someone else pays for a repeat test, I trust the data that we have been given.
 
And additionally from my neighbor’s communication with Lycoming -

“The Challenger filter is not currently a Lycoming approved PMA part. As for PMA certification details, I recommend contacting Challenger or the FAA for details on what requirements they had to meet for PMA status. We evaluated the Challenger filters but due to the reduction in filtering ability led us to not pursue using them in the factory. CubCrafters uses them on their X Cub and NX Cub with the IO-390-D3B6 and probably a few other models. I have not had any negative reports from CubCrafters or operators using this type of filter about its ability to filter. Personally, I do Like the design but would operate on a reduced oil change interval if installed.

Thank you,
Brandon Dildine”
And from his communication with Challenger -

Thank you for reaching out to Challenger Aviation.

After reviewing the information presented, it appears this unauthorized test has no verifiable information. There is no lab name listed, no testing variables nor are there parameters of how these results were determined. From what we can see, there is a partial summary of a full report that will not be released. Therefore, Challenger will not be making a statement regarding the test referenced.

Our Challenger Aviation Products, FAA/PMA certified filter went through rigorous testing upon receiving our STC approval. As we are sure you are aware, that information is proprietary per the FAA requirements. However, if you would like to see what type of data is collected for that certification process you can find it at the following link.


Our certified aviation oil filter has been flying since 2006, with only minor changes made in 2009. We have had wonderful feedback from the pilots in the field flying our certified aviation oil filters.

As far as the non certified aviation oil filters being referenced, we have no response as we do not promote nor encourage the use of non aviation certified filters for use in any aircraft, certified or experimental. The K&P S15 oil filter is not certified for use in any aviation applications.

Thank you again for your inquiry.

Heather Rocco
CEO/Co-Owner
Challenger Aviation Products, Inc.
So if the Challenger filter had performed better than the other filters in the test, would her response be different? 🤔 Highly likely.
Either way I also have to wonder about the confidentiality of the tests performed. You bought and paid for a test protocol just like we do with our oil analysis. Once you receive the results, you should be able to share the information. Wasn't that the point of this whole experiment?
 
Was the filter primed and what kind of primer was used....hahaha. This is turning into filter wars, just like primer wars. I appreciate Dan doing all the work and testing the different filter types. Thanks Dan. :D:D:D
 
After reviewing the information presented, it appears this unauthorized test has no verifiable information. There is no lab name listed, no testing variables nor are there parameters of how these results were determined. From what we can see, there is a partial summary of a full report that will not be released. Therefore, Challenger will not be making a statement regarding the test referenced.
:ROFLMAO:

The “unauthorized” insult is beautiful, in the way that truly stupid things can be strangely beautiful.
 
Outside of the tests here, we should have known the Challengers and K&P's long ago work poorly, but thats not the case. I've never seen any data correlating to elevated metals in oil samples for the engines running these filters. This reminds me of being told N95 masks were supposed to be better at "stopping the spread".

If particle sizes and filter efficiencies mattered that much in the real world we'd all be running bypass filter systems.
 
I've never seen any data correlating to elevated metals in oil samples for the engines running these filters.
Q: how many engines reached 3 - 4 thousand hours on those filters? Anybody here running so long on a reusable filter?
If I understand correctly, Lycoming would be good to go for 2000 h with a pressure screen, but what happens then? Those unfiltered particles must cause increased wear and tear.
 
Some share your perspective. None have shared why they believe "originally designed with nothing more than a screen" makes a Lycoming immune to abrasives in the 5 to 40 µm range.

Dan, with respect, I don't believe anyone ever said that nothing more than a screen makes a Lycoming immune to abrasives in the 5 to 40 um range. There is probably much more particulate and abrasives contaminating our engines past old K&N air filters.
 
Dan, with respect, I don't believe anyone ever said that nothing more than a screen makes a Lycoming immune to abrasives in the 5 to 40 um range. There is probably much more particulate and abrasives contaminating our engines past old K&N air filters.

Absolutely. Poor air filtration is the source of silicon contamination.

2000 hours with just a screen is based on very short oil change intervals as compared to any other kind of IC engine. Perspective...in the US, personal road vehicles average about 38 miles per operating hour. My own truck is a good example, about 155K and 4000 hours on the clock. Every 25 hours would be a 1000 mile oil change schedule, more or less, and of course, 50 hours would be 2000.

Contrast with current standards...7,500 to 15,000 mile intervals, dino or synthetic, for passenger and light truck. The range is 25,000 to 50,000 miles for heavy truck...with really good filtration, both air and oil. It's 500 hours for some of the heavy off road machines,

If I was willing to change the oil in my truck every 1000 miles, a screen might result in reasonable service before overhaul. When my grandfather ran the town garage, 1000 between servicing was normal. Nothing had filters...but that was almost 100 years ago.

Anderson's Garage.jpg
 
As an update the WIX 51515 will not fit on the ECI 0360 angled oil filter adaptor (on the RV-7) as it is too long and the engine mount cross brace prevents the filter lining up with the thread extension. The shorter 51068 fits but if the motor has drooped a little you have to lift it to get the filter started. I am assuming the 51521 would be Ok as it is a bit shorter still but with the same specs as Marvin pointed out. Seems like the WIX can is a little fatter than the Champion/Tempest filters.
Figs
 
As an update the WIX 51515 will not fit on the ECI 0360 angled oil filter adaptor (on the RV-7) as it is too long and the engine mount cross brace prevents the filter lining up with the thread extension. The shorter 51068 fits but if the motor has drooped a little you have to lift it to get the filter started. I am assuming the 51521 would be Ok as it is a bit shorter still but with the same specs as Marvin pointed out. Seems like the WIX can is a little fatter than the Champion/Tempest filters.
Figs

This one under investigation by one of our smarter fellows: Donaldson 551132...synthetic media, small package, spec sheet values in the right range. Not an endorsement, but a good prospect. Do the numbers suggest it would fit in your application?


EDIT, based on Scott's photos below (thank you sir) the dimensions would be just fine.
 
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As an update the WIX 51515 will not fit on the ECI 0360 angled oil filter adaptor (on the RV-7) as it is too long and the engine mount cross brace prevents the filter lining up with the thread extension. The shorter 51068 fits but if the motor has drooped a little you have to lift it to get the filter started. I am assuming the 51521 would be Ok as it is a bit shorter still but with the same specs as Marvin pointed out. Seems like the WIX can is a little fatter than the Champion/Tempest filters.
Figs
I was about to post a similar mention. My 51515XP fits - barely. For reference, I have an IO-320-E1A on a conical mount, with a Casper adapter. The Wix can is definitely fatter than Champion/Tempest, and from memory a bit longer as you note. The shorter series Wix cans should be fine.

Some pics - compared against my S-15. I'd say the Wix has maybe 1/8" clearance from my engine mount upper right arm, and is against my breather tube.
PXL_20240427_141424081.jpg PXL_20240427_141441240.jpgPXL_20240427_141501132.jpg
 
This one under investigation by one of our smarter fellows: Donaldson 551132...synthetic media, small package, spec sheet values in the right range. Not an endorsement, but a good prospect. Do the numbers suggest it would fit in your application?


EDIT, based on Scott's photos below (thank you sir) the dimensions would be just fine.
Looks like a perfect candidate for my application, thinner, shorter, and better filtration specs (17 vs 21), $20.
 
Absolutely. Poor air filtration is the source of silicon contamination.
That’s the info I was looking for!! Thanks Dan. I have about 150 hours on my engine (O-360) and I’ve done two oil analysis’ with Blackstone. For some reason my silicon numbers are high. I have the K&P S-15 “filter”. I’ve ordered a WIX 51647 since I have a standard straight Lycoming oil filter adapter with built in bypass. My measurements indicate that it will fit with the back end going slightly into the firewall bump-in. I’ll take some picks, like the other Scott did and post them for reference. The 51647 is 5.167” tall. The burst strength is 390, which is the only variable I’m unsure about. How much should it need to be? The Tempest and Champions are 600-700 I think.
 
If the engine moves like most do during startup/shutdown, you'll more than dent it. If it breaks the seal against the engine, it'll make a heck of a mess before you shut down.
Agreed - that's too close. I would find another filter. Not all shakes are the same - you might have a bit of a shake during your testing, but sometimes a tricky hot start will cause additional shakes. Also, some shutdowns are not "clean", and there's a lot of shaking. What happens if you lose one cylinder? The engine will shake a lot, so in addition to loss of power, you have just knocked off your oil filter, and lost all your oil. Even losing one plug can make the engine shake more.
 
I was about to post a similar mention. My 51515XP fits - barely. For reference, I have an IO-320-E1A on a conical mount, with a Casper adapter. The Wix can is definitely fatter than Champion/Tempest, and from memory a bit longer as you note. The shorter series Wix cans should be fine.

Some pics - compared against my S-15. I'd say the Wix has maybe 1/8" clearance from my engine mount upper right arm, and is against my breather tube.
View attachment 61552 View attachment 61554View attachment 61556
The engine is going to move more than that clearance allows. 1/8" is just a little too close.....for me, anyway.... :oops: I would not like the mount to be banging against the filter. A filter being moved enough to break the seal or, worse, being broken off could change the course of an otherwise pretty good day....IMHO
 
That’s the info I was looking for!! Thanks Dan. I have about 150 hours on my engine (O-360) and I’ve done two oil analysis’ with Blackstone. For some reason my silicon numbers are high.

Only two possibilities, and likely both. Your air filter is letting it in, or your oil filter is not removing it.

Here, geek out...50 pages for your reading enjoyment: https://www.danhorton.net/VAF/Filter Test Results/Dust and Wear.pdf

I’ve ordered a WIX 51647 since I have a standard straight Lycoming oil filter adapter with built in bypass. The 51647 is 5.167” tall. The burst strength is 390, which is the only variable I’m unsure about. How much should it need to be? The Tempest and Champions are 600-700 I think.

Personally I think 390 psi is plenty, in particular when using multigrade oil so pressure doesn't spike if a cold start includes too much RPM.

Champion and Tempest, being certified filters, are assumed to meet the requirements of SAE ARP 1400-B. Here's what it says:

4.5.3 Pressure: The filter assemblies shall perform satisfactorily when subjected to the following pressures (all pressures are gage, unless otherwise specified).

4.5.3.1 Operating Pressure: Shall be 689 kPa (100 psig).

4.5.3.2 Proof Pressure: The proof pressure requirements shall be specified by the engine manufacturer. Recommended proof pressure value is 2758 kPa (400 psig) minimum. The filter shall exhibit no external leakage or permanent deformation when tested per 5.4.4.

4.5.3.3 Burst Pressure: The burst pressure shall be 3447 kPa (500 psig) minimum. When tested per 5.4.11, there shall be no leakage greater than 1 drop up to the specified minimum burst pressure.
 
Okay, so as a data point we've agreed the 51515 will not practically fit on a Casper, at least on a conical IO-320. I'm also looking at the 51307 or the K&N HP-1002. The K&N has been mentioned in years past in the archives as working on a Casper. Other than Summit mentioning the K&N's burst pressure at "over 550", a bypass pressure of 11-14, and filtration "up to 10 microns", I can't find analysis data on how good it is. Any suggestions on other models to look at?
 
Okay, so as a data point we've agreed the 51515 will not practically fit on a Casper, at least on a conical IO-320. I'm also looking at the 51307 or the K&N HP-1002. The K&N has been mentioned in years past in the archives as working on a Casper. Other than Summit mentioning the K&N's burst pressure at "over 550", a bypass pressure of 11-14, and filtration "up to 10 microns", I can't find analysis data on how good it is. Any suggestions on other models to look at?
Yes. The Wix 51348 is what crosses to the K&N HP1002. It also comes in the Wix 51348HP which has synthetic filter element. The K&N HP1002 is what was recommended by Casper Labs.
 
will not practically fit on a Casper
Will not practically fit a Casper on your plane without the spacer (at least, I can't see a spacer in your photos). It looks to me like your engine mount would provide enough clearance if your oil filter was mounted a little closer to the firewall.
 
Will not practically fit a Casper on your plane without the spacer (at least, I can't see a spacer in your photos). It looks to me like your engine mount would provide enough clearance if your oil filter was mounted a little closer to the firewall.
Mounting closer to the firewall would impede the clearance to remove my #2 battery. The perspective of the one picture makes it look like there's quite a bit of space, which there is until you slide the battery straight up out of the battery box. :)
 
Mounting closer to the firewall would impede the clearance to remove my #2 battery. The perspective of the one picture makes it look like there's quite a bit of space, which there is until you slide the battery straight up out of the battery box. :)

Makes sense! I bought the same filter adapter and haven’t gotten around to fitting it for a similar reason. The long extension makes it go straight into the oil separator (with limited space to be relocated) and the shorter extension doesn’t give a comfortable enough clearance from the engine mount.
 
Only two possibilities, and likely both. Your air filter is letting it in, or your oil filter is not removing it.

Here, geek out...50 pages for your reading enjoyment: https://www.danhorton.net/VAF/Filter Test Results/Dust and Wear.pdf



Personally I think 390 psi is plenty, in particular when using multigrade oil so pressure doesn't spike if a cold start includes too much RPM.

Champion and Tempest, being certified filters, are assumed to meet the requirements of SAE ARP 1400-B. Here's what it says:

4.5.3 Pressure: The filter assemblies shall perform satisfactorily when subjected to the following pressures (all pressures are gage, unless otherwise specified).

4.5.3.1 Operating Pressure: Shall be 689 kPa (100 psig).

4.5.3.2 Proof Pressure: The proof pressure requirements shall be specified by the engine manufacturer. Recommended proof pressure value is 2758 kPa (400 psig) minimum. The filter shall exhibit no external leakage or permanent deformation when tested per 5.4.4.

4.5.3.3 Burst Pressure: The burst pressure shall be 3447 kPa (500 psig) minimum. When tested per 5.4.11, there shall be no leakage greater than 1 drop up to the specified minimum burst pressure.
Thanks for the reply Dan. After skimming through the link (I’m saving this to completely geek out later to try and understand the total levity of what this report is telling me), I think the airbox isn’t the problem. After a little more than 1 1/2 years and cleaning/oiling my K&N filter per manufactures recommendations twice in about 125 hours since new, I think my air filter must be working as well as can be expected. It’s clean and fits my airbox very snugly. I’m thinking that the elevated silicon is from inadequate oil filtering. I’ll find out through future oil analysis. I’m going to change my S-15 reusable filter for a WIX tomorrow or the next day. Engine oil will remain in the crankcase, since it’s only been less than 15 hours since the last change, and the fact that my airport will be closing our only runway for 4-6 weeks for resurfacing on June 3. Before the airport closes, I'll fly it and change the oil and the almost new WIX filter, start it to check leaks, and then preserve it as much as possible. That next oil/filter change will be with another WIX, or a Champion, depending what the first WIX looks like when I change it. New oil analysis after that newest oil/filter change. I’m hoping silicon levels will decline.

I do use Phillips 20W50 oil, and always preheat during the cold months in Cincinnati, so maybe the 390 burst isn’t a problem with the WIX/NAPA 1647 I’m using.
 
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I'm not so sure about that. It's hard for me to believe that people actually thought a reusable filter would work as well as a traditional (disposable) filter. I think the people that bought Challenger filters had other motivations (e.g. saving money on oil changes). There will always be people trying to save a buck regardless of how it affects their engine. Just look at the unleaded fuel thread.

I'm not so sure about the comment regarding saving a buck. During COVID there were times when we couldn't get filters, and if you happen to find them the price was outrageous. The reusable filters looked like a good alternative at the time. I've since removed them from my aircraft. As much as I would like to sell them, I don't think I can in good conscience sell them for aircraft use, given these results.

Vic
 
...I think the airbox isn’t the problem. After a little more than 1 1/2 years and cleaning/oiling my K&N filter per manufactures recommendations twice in about 125 hours since new, I think my air filter must be working as well as can be expected. It’s clean and fits my airbox very snugly. I’m thinking that the elevated silicon is from inadequate oil filtering.

It has to get into the engine somehow. Silicon is not a byproduct of combustion or wear. Blackstone's Jim Stark says some can leach from silicone sealants, and some can be found in oil additives. Other than that, it's airborne dirt.

I was looking at some air filter stuff on the net. There is one good comparison done very much like our oil filter check, by a fellow who actually makes the ISO-standard air filter test machines. The results were what most of us already know; the K&N wasn't fabulous compared to the conventional filters, something like 96% efficient vs others in the 99's. Way, way better than no air filter, but do note 96% means 4 particles get through for every 100 presented, while 99 means 1 particle.

I just had my FM-200 off for the sump flange mod. After 1200 hours the throttle plate and bore were indeed a bit grimy. Just for fun I intend to pick up the Baldwin conventional which crosses to the K&N I'm using and see if it shows any loss of manifold pressure. The other test would be water ingestion; does the media withstand rain in flight?

If anyone wants to talk about air filters we can start a separate thread.
 
...and if you happen to find them the price was outrageous.
See, that was my point - trying to save money :)

If there was literally no alternative because traditional filters weren't available at any price, then yeah, installing re-usable filters as a temporary solution makes perfect sense. I would probably have done the same thing but cut my oil change interval in half.
 
See, that was my point - trying to save money :)

If there was literally no alternative because traditional filters weren't available at any price, then yeah, installing re-usable filters as a temporary solution makes perfect sense. I would probably have done the same thing but cut my oil change interval in half.
Yup -- we all lost our minds during the 'rona years; caused us to start doing oil changes every other day. That, coupled with supply chain issues (?!) , and Champion, Tempest, fell behind in production.

....But that was in 2022. We're all fat and happy again, with personal stockpiles of Charmin 2ply and Champion 48110-1's :)
 
Two more sources for nipples. $3.29 and $3.99.


 
Straight thread on the nipples salvaged from the aviation filters.


Amazed at the money they are getting for these nipples considering there are literally trash cans full of them at any FBO. Maybe I can start a retirement gig by harvesting all these oil filters and re selling the nipples!

Mike, extracted one from a Tempest, and it seemed like the short threads, previously in the filter end cap, were tight when screwed into a new filter. I assume those threads would also be tight in a filter adapter.

I suspect they are non-standard, intended to be tight so the nipple always unscrews with the filter. Are the Champions the same?
 
I'm not so sure about the comment regarding saving a buck. During COVID there were times when we couldn't get filters, and if you happen to find them the price was outrageous. The reusable filters looked like a good alternative at the time. I've since removed them from my aircraft. As much as I would like to sell them, I don't think I can in good conscience sell them for aircraft use, given these results.

Vic
I'm planning to sell mine on Ebay, presumably to an automotive customer.
 
Is a paper filter media better than a steel mesh? I would say yes. However, I honestly think that when the engineers at Lycoming asked each other, “ should we put an oil filter on this thing? “ the likely response was “gee Bill why? It’s gonna rust from the inside out long before it will need a filter.”

Honestly, a reusable FAA/PMA, Lycoming approved oil filter vs one from Walmart IMHO shouldn’t warrant a thread this lengthy, when for most of us, who are not putting 500 hrs/year on their engine, the bigger threat is likely going to be corrosion.

Everyone’s mileage will vary and at the end of the day, go with whatever floats your boat.
 
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