I am, by nature, a skeptic. I do not believe in oil or fuel additives and have yet to see a well-controlled study to prove any benefit.
Has any testing been done where a statistically significant number of engines have been run side by side?
(Half with additives and half without) under the exact same conditions at the exact same power settings and then torn down to evaluate the effectiveness of an additive?
In the PowerPoint I see photos of sludge, rust, pitting, wear, etc. from an xxhr engine. How was the engine operated/maintained. What conditions did it fly under (crop duster, jump plane)? Where was it operated (Mississippi Delta or Dry Desert)? LOP or ROP? Flown by a rookie pilot or an old pro?
Same for the “after additive “photos. These remind me of the lifestyle lift commercials where a 72 year old hag is shown with scruffy gray hair and warts in a burlap dress in the before photo and then after a face lift she is a blonde, no warts perfect hair and in an evening gown.
I am also intrigued by one power point slide (I think number 12/41 that shows “zones” of fully, partially, and non-combusted fuel and water in the blow by. While this makes theoretical or actual sense, is there any test rig where this has been or can be measured or proven to exist?
I am also not swayed by quantitative statements relative to gallons of water per unit of fuel or time. Etc.
Most of this goes out the exhaust. Most of what remains certainly, when it condenses and falls to the lowest point in the engine (oilpan) where it does little harm. I seriously doubt these molecules of badness conspire to seek out cam lobes, tappet surfaces etc. to do their misdeeds.
I am also curious as to the origins of the “theory” that an engine must be preheated by “flying it” and that a ground run up to operating temp causes harm while flying it to operating temp is good. Water starts to evaporate at relatively low temps (compared to ambient) and heads out the breather as vapor
All the while you are making more of it by running the engine. I can see the “theoretic benefit of” the hotter you get the oil before an oil change the more you drive those molecules of badness into solution and thus remove them with the oil. My own belief (unproven by testing) is that the hotter the oil at oil change the “thinner” less viscous it is and the more of the old stuff you get out.
I also believe that one size does not fit all. There are Lycomings, Continentals, Franklins, Rotax, Rotec, etc.
There are Carbureted engines, fuel injected engines, turbocharged and supercharged engines. Each has its strengths, weaknesses, and needs.
The other thing that seldom sways me in my evaluation of additives are endorsements.
Sean Tucker and Mike Busch were mentioned in the posts above not specifically as endorsements but as users of additives.
I don’t know Sean Tucker but I understand he is a heckuva good aerobatic pilot. “What exactly” is it that makes his use of an additive a good reason for you to use it?
Mike Busch (from personal knowledge) is a heck of a good pilot, an excellent A&P/IA, a meticulous owner when it comes to maintenance, and an extremely knowledgeable guy. I pretty much emulate Mike in the way I have operated FI and Turbo/supercharged engines and when he speaks I listen.
I think Mike’s success in engine operation/longevity is due more to his meticulous diligence in operating them and not so much from additives.
I do not know whether Camguard or Avblend help an engine or not. I certainly have seen no testing or data that can prove they do not help an engine and I have seen no data or theory to suggest that they harm an engine.
I think both make reasonable theoretical arguments that their products do what they say as opposed to MMO. But I think most evidence that profess the use of additives is anecdotal rather than scientific and result based fact.
I do not criticize folks who use avblend or camguard for they may be doing the right thing and I may be wrong in my thinking.
I do not believe in additives based purely anecdotal evidence, and not based on scientific evidence or fact. Over many decades and talking to thousands of engine owners and operators along with personal experience I find that an overwhelming majority of engines (with 2 caveats) make or exceed TBO with little or no maintenance problems, no matter how well or poorly they are maintained or operated. They do so without additives.
The 2 caveats are those engines that sit for months on end and are seldom used and big bore Turboed engines that are being whipped to maximum capacity.
My purpose of this post is not to diss additives, more to promote skeptical thinking, and to get users to ask questions when presented with “apparent” facts by “apparent” experts.
How do you know :that: happens?
EXACTLY what testing did you do to prove what you say is true? Please describe to me your test facilities, equipment, and methods.
TRUST BUT VERIFY. Our aviation dollars are shrinking in value and they are too precious to spend on something unless you are sure it is of value.