Mike Busch from the Savvy Aviator does some Q&A

Bob Klee:

I was under the impression we could not use Camguard in Turbo engines? This from their website: "Turbocharged engine acceptance pending", so is it our call if we use it or not?

 

I've researched this quite extensively (including with my Principal Maintenance Inspector at the FSDO who oversees my IA activities).

There is no such thing as an FAA-approved oil additive.

ASL Camguard has been "accepted" by the FAA Engine & Propeller Directorate for normally aspirated engines. What that "acceptance" means is that the FAA wrote ASL a letter saying that they are persuaded that Camguard "does no harm" when used in normally aspirated engines.

ASL has requested such "acceptance" from the FAA Engine & Propeller Directorate for turbocharged engines, but the FAA has indicated that they will require ALT to submit the results of endurance tests that ASL anticipates will take them at least two years to complete. Thus, do not expect FAA type acceptance any time soon.

There is no regulatory requirement that an oil additive be FAA "accepted." People have been using Marvel Mystery Oil in aircraft engines for five decades (at least) and I've yet to hear of one of them being busted. I actually used a little in one of my engines years ago (the statute of limitations has run) when I detected some valve lifter clatter. The lifter clatter cleared up. NOTE: This is NOT an endorsement of MMO!!! I do not use it and do not recommend it except in abnormal circumstances.

The issue of TCM acceptance is a totally different matter. TCM specifically does not accept ANY aftermarket oil additive, even those that have been FAA accepted. In fact, TCM states that the use of any aftermarket lubricants may void TCM's warranty. The reference is TCM SIL99-2B. In fact, however, I am unaware that TCM has ever denied warranty coverage based on the use of any aviation oil additive, and it's clear from the wording of SIL99-2B that TCM is primarily concerned about the use of automotive products in aircraft engines.

Bottom line: I have written extensively and spoken publically about my own experience using Camguard in the turbocharged engines of my own airplane. I have done this quite high-profile under FAA scrutiny and I have received no push-back from anyone in the FAA. I have discussed this issue face-to-face with my FAA PMI, who told me that while he's not exactly thrilled about my public endorsement of Camguard in the context of turbocharged engines, he knows of no regulatory issues that would make such use problematic.

As for TCM, their stance against the use of aftermarket additives applies to all additives and all engines equally. In theory, TCM could deny warranty coverage on the basis of the use of any aftermarket additive in any TCM engine, whether normally aspirated or turbocharged. In practice, I have never heard of a single instance in which they did so.

The language is SIL99-2B is clearly CYA boilerplate. With respect to Camguard, the issue is moot anyway because TCM does not offer any warranty for engines in SR22 Turbos (Cirrus provides the warranty for those engines).

SIL99-2B has a lot of problems. For example, I have been using Aeroshell W100 in all my TCM piston engines for well over 4 decades. If you look at the list of approved aircraft oils in SIL99-2B, you'll observe that Aeroshell W100 is NOT on the list! (Aeroshell W100 Plus is on the list, but the non-Plus variety that I have always used is not on the list.) However, SIL99-2B also says:

Lubricating oils qualified for use in Teledyne Continental Motors engines are required to meet SAE (Society of Automotive Engineers) specifications.

SAE specification J 1899 (formerly MIL-L-22851) is the approval for aircraft piston engine ashless-dispersant oil.

SAE specification J 1966 (formerly MIL-L-6082E) is the approval for aircraft piston engine non-dispersant mineral oil.

Aeroshell W100 meets SAE J 1899 and MIL-L-22851 (says so right on the bottle).

Just use whatever oil and additives you think best (as long as they're intended for use in piston aircraft engines), and don't worry about the FAA or TCM. There is no oil police.

My recommendation is to use either Aeroshell W100 single-grade or Phillips X/C 20W-50 multigrade and to add at least 5% ASL Camguard (1 pint per 10 quarts) at each oil change. (A little extra Camguard doesn't hurt, and a 10% concentration is recommended as a "pickling oil" if the aircraft will be idle for a significant length of time.) For our Savvy clients, we recommend W100 with Camguard as our first choice unless the airplane is likely to encounter unpreheated cold-starts in sub-freezing OATs, in which case we recommend Phillips 20W-50 with Camguard.

We have several Cirrus clients who had lousy looking oil analysis reports and cleaned up nicely after a couple of oil changes with Camguard. I have seen the same thing occur in at least a dozen engines in non-Cirrus aircraft (Bonanzas, Centurions and twin Cessnas) as well. I have documented my own oil analysis results from my own airplane in considerable detail in several aviation magazines. I am personally persuaded that the stuff works quite well and has no adverse side effects. (If I wasn't , I sure wouldn't be using it in my own engines, which are now approaching 200% of TBO.) I used Camguard quietly for almost two years before I started talking about it in public, because I was skeptical and wanted to see plenty of data before putting my reputation on the line.

Mike Busch (A&P/IA CFIA/I/ME)
2008 National Aviation Maintenance Technician of the Year
Savvy Aircraft Maintenance Management, Inc. (SAMM)
Savvy Aviator, Inc.

 

 


 

Michael Stachour:

This question is probably for Mike, but does anyone use Avblend instead of Camguard and what is the difference?


Decades ago, when AvBlend was first introduced, we did a fairly extensive test in some twins where one engine was treated with AvBlend and the other engine was untreated. We studied the oil analysis results and could never see any real evidence that AvBlend had any beneficial effect. The tests were overseen by Howard Fenton of Tulsa, who at the time operated the preeminent aviation oil analysis lab in the country (subsequently sold to Blackstone Labs). However, we also saw no evidence that AvBlend did any harm. Consequently, my position on AvBlend has been that I don't use it and don't recommend it but at the same time I don't discourage owners from using it if it helps them sleep better at night.

There are other additives (like Microlon and Slick 50) that actually have the potential to harm engines, and those I actively discourage.For example, Microlon was FAA accepted in 1979, but you really don't want to use it. It's a PTFE (Teflon)-based additive, and Dow Chemical (the manufacturer of Teflon) specifically warns against using Teflon in any piston engine because of the risk of a phenomenon called "Teflon flocking" in which microscopic particles of PTFE can wind up aggregating into macroscopic clusters large enough to clog the tiny oil passages in hydraulic valve lifters and turbocharger spindle bearings (among other things). This phenomenon is rare, but in my view it's just not worth the risk.

Tests on oil additives containing PTFE conducted by the NASA Lewis Research Center reported:

"In the types of bearing surface contact we have looked at, we have seen no benefit. In some cases we have seen detrimental effect. The solids in the oil tend to accumulate at inlets and act as a dam, which simply blocks the oil from entering. Instead of helping, it is actually depriving parts of lubricant." (Rau).

The Microlon story is a good example of why FAA acceptance of oil additives is pretty meaningless. The FAA accepted Microlon (essentially saying it does no harm) without paying any attention to the warnings from the manufacturer of its principal ingredient (saying it could do harm) or the NASA Lewis tests (that said the same thing). And as always, FAA acceptance says nothing about whether or not the additive has any tangible benefit; it is limited to evaluation as to whether the additive can do harm (which in the case of Microlon wasn't exactly thorough).

By the way, many years ago John Deakin did a highly publicized before-and-after test of Microlon in his personal Bonanza and was unable to substantiate any of the claims made by the distributor of the product. The test was done at my home airport, Santa Maria California, and I witnessed it firsthand. If memory serves, George Braly might have been involved as well.

All this explains why I have been so skeptical about all these miracle-in-a-can additives that have come out over the years, and why I spent nearly two years evaluating Camguard before starting to recommend it to others. In the aviation oil additive business, the signal-to-noise ratio is very low.

Mike Busch (A&P/IA CFIA/I/ME)
2008 National Aviation Maintenance Technician of the Year
Savvy Aircraft Maintenance Management, Inc. (SAMM)
Savvy Aviator, Inc.

 


Bob Klee:
I'd like to use Camguard, but worried about the potential decline of a warranty claim by TCM if I have an engine problem. It is not "approved" for Turbo engines:( Any thoughts on that ?


TCM reserves the right to decline warranty coverage for ANY engine (turbo or normally aspirated) that uses ANY aftermarket additive (whether or not FAA-accepted). [Reference is TCM SIL99-2B.]

To the best of my knowledge (and I follow this stuff pretty closely), TCM has never actually declined warranty coverage for that reason.

There is no such thing as an FAA-approved oil additive.

The FAA has "accepted" Camguard for use in normally-aspirated engines. This "acceptance" means only that the FAA is satisfied that Camguard "does no harm" to such engines. Such FAA acceptance is not required in order to use the additive (there is no regulation requiring additives to be FAA-accepted), and TCM reserves the right to deny warranty coverage even for FAA-accepted additives (since TCM does not recognize FAA acceptance).
FAA acceptance is essentially meaningless. Back in the 1980s, the FAA granted acceptance to a PTFE-based oil additive called Microlon, despite the fact that both the manufacturer of PTFE (DuPont) and NASA Lewis Research Center both cautioned against the use of PTFE as an oil additive because it can harm the engine. Microlon remains FAA accepted nevertheless.
See this thread (above two comments) for more details.

Mike Busch (A&P/IA CFIA/I/ME)
2008 National Aviation Maintenance Technician of the Year
Savvy Aircraft Maintenance Management, Inc. (SAMM)
Savvy Aviator, Inc.