Putting CamGuard to the Test

So reading these posts a few say look how clean the engine is with it. Is it from camgaurd or the oil itself? Maybe its good maintencae , filtration and getting the engine up to temp and hot enough to boil out the moisture. Phillips XC has inhibitors already in it. You would think if the xc itself didnt work without it, they would change the formula so it did or they wouldn't stay in business.
 
I could show you a 1500 hour engine that looks very similar inside without cam guard. So no
This engine was 40 years old and 1700 hrs when I removed the clys for an inspection. Look how nice the rings were sealing. This engine has never used cam guard. The inside looked like the above picture, spotless inside and the cam and lifters looked good too all without cam guard.
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These lifters are the same 40 years old and 1700 hrs of use and no cam guard. These are out of a H2AD engine that early on ate cam and lifters.
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No rust in the valve covers, this engine only flew 9 hrs during the 10 years prior to me flying the plane. At first I was flying this plane for a friend before I bought it after a annual inspection and this engine inspection. I put it back together after cleaning the rings and pistons and flew it for another 100 hrs. It was a surprise how nice it was inside after sitting so much.
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They may have protected those engines in the video but they sure gave the paint on the airplane hell using the unprotected wings as tables.
 
The only definitive evidence would be a controlled experiment. Take a fleet of aircraft, maintain half with Camguard and half without, subject both to same operating conditions and practices, and see which half gets better TBO. Sample size would have to be large enough to offset standard deviation of individual engines. A large flight school like Embry Riddle or ATP could probably accomplish that. To make the test results fit the larger GA population, each aircraft would need to be subject to occasional 3 month AOG events.

Individual anecdotes are interesting but prove nothing. Likewise for attempts to replicate engine conditions in an external environment, like the Avweb test where they sprayed salt water on engine parts. Engineering tests like ASTM can give more rigorous insight into the performance of additives in a controlled environment, but again that is only indirect evidence of what those substances do in an actual operating environment.
 
Hmm, lets see. CamGuard is about $27 a bottle. 50 hour oil changes.

TBO is 1500 hours, so 30 oil changes, so $810 for CamGuard.

Overhaul cost is about $40,000. So $26.66 an hour. So if CamGuard gives you 30 more hours, it is a wash.
 
This engine was 40 years old and 1700 hrs when I removed the clys for an inspection. ...
I'm curious: why did you tear it down to inspect? Where there symptoms indicating a problem?

Hmm, lets see. CamGuard is about $27 a bottle. 50 hour oil changes.
TBO is 1500 hours, so 30 oil changes, so $810 for CamGuard.
Overhaul cost is about $40,000. So $26.66 an hour. So if CamGuard gives you 30 more hours, it is a wash.
Another way to think about it: my marginal cost of the next hour of operation is about $60 (fuel & oil). Camguard costs about $30 every 50 hours, so that's 60 cents per hour, or 1% of my hourly cost. If you consider total hourly cost including fixed expenses, it's even cheaper.

Camguard costs about the same as doing UOA. But over 15 years of doing UOA regularly and watching trends, it has given me false negatives (clean reports on an engine whose cams were corroding) and false positives (high metals on a perfectly healthy engine), so I consider it useless and stopped doing it.
 
I'm curious: why did you tear it down to inspect? Where there symptoms indicating a problem?
I'm
My guess....40 year old engine that's been sitting. An engine that is notorious for dirty deeds when doing just that. Now owned by a guy that rebuilds race engines that would like some piece of mind. When he says he cleaned the rings, I'd suspect it was burning some oil or blowing it out.

@Gary Ward how'd I do?
 
I recall an interview with another chemist who looked into CamGuard and works on oils for the racing industry. I forget which company he worked for, but it was one of the larger players.
He stated a few things I found interesting which match what Ed K. has stated in multiple interviews.
1. As a general rule, aviation oil runs out of capacity to absorb combustion byproducts (lead, acid...) long before the oil loses its effectiveness at both wear and lubrication protection.
2. The burn Mobil ran into with synthetics, has made the owner community extremely adverse to change, and the manufacturers are not rewarded for R&D.
3. Exxon published/leaked information they had found on adding enough additives to engine oil to match oil longevity, along with the market analysis that showed raising the additives enough would price them out of the market.
4. Due to the first point, if you are aggressive on the oil changes, CamGuard and/or other additives will not help.
5. In the automotive and racing markets, additives do not make economic sense. The oils in these markets span the gamut from very basic to exotic specialty blends. Additives would just be more expensive then getting the correct oil.

He said he uses the cheapest oil with CamGuard; but dodged on making a recommendation. :D

My take, I could change the oil every 20-25 hours or when the plane would sit for a few weeks. Or I could add CamGuard and be able to get 35-40 hours. That made it worth it to me.

Tim
 
... My take, I could change the oil every 20-25 hours or when the plane would sit for a few weeks. Or I could add CamGuard and be able to get 35-40 hours. ...
My understanding of Camguard is not that it extends the drain intervals, but it resists the corrosion that develops when the engine sits unused. If the airplane is flown every day or nearly so, for example with a flight school, you don't need it. But most privately owned airplanes sit a week or more between flights, at which point Camguard may become useful.
 
My understanding of Camguard is not that it extends the drain intervals, but it resists the corrosion that develops when the engine sits unused. If the airplane is flown every day or nearly so, for example with a flight school, you don't need it. But most privately owned airplanes sit a week or more between flights, at which point Camguard may become useful.

If you listen to Ed K a few times CamGuard does a few things, two of which apply to this discussion.
1. Helps leave a coating on the metal in the engine to reduce corrosion.
2. CamGuard includes "sacrificial" additives which absorb the combustion blowby.

The combination of these two things is what reduces the engine wear. For most pilot owners, the engine sitting for extended periods exposes the metal to the corrosive effect of the combustion byproducts rapidly increasing the wear cycles.
If the plane is in a flight school, generally the assumption is the plane is flown enough that the first condition will not apply. And if the plane is not sitting in a bath of corrosive chemicals, having a buffer to absorb it is less critical.

Tim
 
This engine was 40 years old and 1700 hrs when I removed the clys for an inspection. Look how nice the rings were sealing. This engine has never used cam guard. The inside looked like the above picture, spotless inside and the cam and lifters looked good too all without cam guard.
017_2.jpg

These lifters are the same 40 years old and 1700 hrs of use and no cam guard. These are out of a H2AD engine that early on ate cam and lifters.
072.jpg

No rust in the valve covers, this engine only flew 9 hrs during the 10 years prior to me flying the plane. At first I was flying this plane for a friend before I bought it after a annual inspection and this engine inspection. I put it back together after cleaning the rings and pistons and flew it for another 100 hrs. It was a surprise how nice it was inside after sitting so much.
064.jpg


Three words: location, location, location.

Ohio is not coastal Florida. If the plane is in an area where the atmosphere tends to promote corrosion, CamGuard will likely be of some help. If it's not in such a location, CamGuard might not make any real difference.

I'm in Florida. I use XC 20W50 + CamGuard. Does it help? Probably. How much? No idea. Does it do any harm? Nope.
 
My guess....40 year old engine that's been sitting. An engine that is notorious for dirty deeds when doing just that. Now owned by a guy that rebuilds race engines that would like some piece of mind. When he says he cleaned the rings, I'd suspect it was burning some oil or blowing it out.

@Gary Ward how'd I do?
You hit the bullseye Racerx,
Long story...
I started flying it at 1416 hrs after sitting for 10 years and like said it was the H2AD engine that did not have the T mod. I flew it to 1725 hrs. before I took it apart. I was doing leak downs at every oil change was noting a couple clys were going down and the oil usage was getting worse. And it was oil fouling a lower plug after about 50 hours. Also concerned about the cam although the oil analysis were good. My AP encouraged me to at least pull the lifters to look since it is easy to do on a H2AD, so I did. They looked weird to me at first. Turns out they had some corrosion around the edges but there was no spauling and the cam lobes looked good.

At that time I was going back and forth between taking it across town to Signature engine for a overhaul or ordering a rebuilt engine from lycoming. My AP even said we could do the overhaul our self's but I wasn't feeling it at the time.

I asked Signature if I could have the cyls back as hangar conversation pieces and he said no they don't return any used parts. Then he said if I wanted the old clys to take them off myself before I brought the engine to them.

So I did thinking I was going to overhaul and removed the clys. But the crankshaft was a concern because it had more than the allowable pits in the snout and I knew Signature would make me buy a new crank. And that would take more than 7 weeks for the overhaul and then the total cost would be more than the lycoming zero hour rebuilt engine.

So I decided to put it back together and keep flying it while waiting for the lycoming rebuilt. Wasn't sure how much longer the cam and lifters were going to last and at least one cly needed valve work since it continued to oil foul a lower plug. I only had it apart for 7 days during Xmas break 2019.

Another thing I found which I have never noticed before on any engine was 3 of the pistons had the ring gaps lined up to one another. That was strange. So of course I cleaned the ring grooves in the pistons and spaced out the ring gaps when I put it back together.

Then I had major buyers remorse after ordering the new engine because the old one ran so good after reassembly.
The leakdown numbers went up and the oil usage went from 1qt to 4 hours to 1qt to 8-9 hours. The clean rings really helped. So I hurried up and flew the heck out of it(100 hrs) and waited until the last minute to make the swap and still get the core back to lycoming within 90 days of receiving the rebuilt engine from lycoming.
I did the engine swap July 4 weekend 2020 in 6 days. Already had updated the hoses, scat tubing and other stuff before the engine swap allowing me to do it in a week. Can't imagine having it apart for months waiting on a overhaul. Now the rebuilt engine has 645 hrs and is running well. 1 qt to 12-14 hrs.
That's the story.
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A large flight school like Embry Riddle or ATP could probably accomplish that. To make the test results fit the larger GA population, each aircraft would need to be subject to occasional 3 month AOG events.
Nope. Airplanes that fly every day are NOT a good test, as they get hot and drive off the moisture.

Most training planes already make TBO. It is the owner flown ones that need help.

And any study would need to cover environmental conditions. If I lived in Arizona, I would not bother with CamGuard. I life in the mid-Atlantic, less than 15 miles from the water in a humid climate. WAY different situation.
 
Anyone know how Ed Kollin is doing....last I heard he was sick with COVID and recovering. That was a few years ago at Oshkosh.

Ed's a good guy. I know him from he and I based our airplanes at Princeton all those years ago. I believe he's recovered well.
 
Hmm, lets see. CamGuard is about $27 a bottle. 50 hour oil changes.

TBO is 1500 hours, so 30 oil changes, so $810 for CamGuard.

Overhaul cost is about $40,000. So $26.66 an hour. So if CamGuard gives you 30 more hours, it is a wash.
I quit reading at 50 hour oil changes.
 
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The only definitive evidence would be a controlled experiment. Take a fleet of aircraft, maintain half with Camguard and half without, subject both to same operating conditions and practices, and see which half gets better TBO. Sample size would have to be large enough to offset standard deviation of individual engines.
Another way is a cohort study.

And I can do something that's close to that, using Blackstone oil-analysis data.

Blackstone provides a column called "Universal averages," which is for the entire fleet using a particular engine. I show Blackstone fleet data for the Continental IO-550-N27, which is the naturally aspirated engine in the SR22. I have the numbers going back to 2012, when Camguard was starting to be adopted , but not yet as widely as now.

This table shows ppm of iron (a wear metal), and calcium (which is in Camguard).

year Fe Ca "universal averages"
2012 49 39
2013 49 46
2014 47 50
2015 46 51
2016 46 53
2017 45 54
2018 44 54
2020 44 53
2022 44 54
2024 44 47

2012 - 2017 more and more Cirrus owners were starting to use Camguard, and during that time span the averages for Fe diminished about 10%. Beyond 2017, not much change in either Camguard (Ca) use or wear metals (Fe).

I'd say that's decent evidence, for an entire fleet of many hundreds or thousands of similar engines, that adoption of Camguard results in 10% (or more) reduction in wear metals. (The reason that I say "or more" is that usage of Camguard didn't go from 0% to 100% of the fleet during that period of time).

I'd bet that there are PoA members who have Blackstone reports going back earlier than mine for a particular engine - it would be interesting to see those numbers.
 
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The big issue is, you need a large sample size of planes that don't fly often. So it makes it hard to get two groups with the same use pattern
 
50 hours is long term? :rolleyes:
You'll have to ask Larry Nelson that question.

I'm not a Camguard user but I've followed what he has posted thus far and hopefully he will continue his updates. These short term findings do seem to confirm that the stuff works as advertised. I'm seriously considering adding it to my engine.

You got any other testing data on Camguard to share? ;)
 
Any goofballs still adding Marvel's Mystery Oil to gas and oil? The nutty anecdotal claims were always good for a laugh. I remember that being a big thing a while back. Talk about a boondoggle.

People have no idea the chemical composition, but are happy as clams to jigger a can in their oil and a cup or two in the fuel tank.

A person has to like the mint scent added to it though.
 
Any goofballs still adding Marvel's Mystery Oil to gas and oil? The nutty anecdotal claims were always good for a laugh. I remember that being a big thing a while back. Talk about a boondoggle. A person has to like the mint scent added to it though.
I'll use it as a ring wash with kerosene....it's a good solvent.
 
Any goofballs still adding Marvel's Mystery Oil to gas and oil? The nutty anecdotal claims were always good for a laugh. I remember that being a big thing a while back. Talk about a boondoggle. A person has to like the mint scent added to it though.

Yes I use it. I'm addicted to the aroma. Works well mixed with 100LL when looking for a leaking valve with a cylinder head on the bench ...
 
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