Camguard and spark plug deposits

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10,796
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Jupiter, Florida
I'm running Camguard at the proper ratio in various aircraft. In my personal Cessna (200HP IO360) I'm discovering excessive spark plug deposits all of a sudden. It coincides with my use of Camguard. The deposits are located deep inside the lower plugs, not near the electrode, but down inside, by the insulator. They are brown/tan in color, looking kind of like dried dirt. They are not "rock hard" like carbon and lead deposits. They can easily be picked out by a piece of safety wire or paper clip. The deposits are chunky in nature and are quite large. I can easily break up the chunks and it looks like dust/dirt. My best guess is that since my engine consumes about 1 quart in 4-6 hours, I'm seeing the additive in Camguard forming this deposit. By 10 hours, the lower plugs are full of deposits. Weird... They don't seem to affect how it runs. I have not changed oil brand, type or viscosity. Nor have I changed any other parameters. A quick look inside the cylinder reveals nothing unusual.
 
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47
Location
NJ
In over 11 years and millions of hours of Camguard use I have never heard of anything like what you describe. I am sure you are using Camguard Aviation at 5% by volume but what oil are you using? There is nothing in Camguard that will form the ash deposits you describe. Can you send me a half a gram or so of this deposit? I would be interested in analyzing it. Ed Edward Kollin Technical Director Aircraft Specialties Lubricants
 

Cujet

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Messages
10,796
Location
Jupiter, Florida
If I see it again, I will save some. I have to wonder what it is, if not related to camguard. Yup, followed directions. I do not use any other additives in the fuel or oil. AS 15W-50 SS. I will try to oxidize some camguard and see what happens.
 
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Messages
47
Location
NJ
I would think the Aeroshell would give more deposits from the phosphorus content. You can try switchimg to Phillips 20W-50 and see what happens. And you will save yourself some money. Do you add additional Camguard when you add makeup oil? Ed
 
Originally Posted By: Cujet
I'm running Camguard at the proper ratio in various aircraft. In my personal Cessna (200HP IO360) I'm discovering excessive spark plug deposits all of a sudden. It coincides with my use of Camguard. The deposits are located deep inside the lower plugs, not near the electrode, but down inside, by the insulator. They are brown/tan in color, looking kind of like dried dirt. They are not "rock hard" like carbon and lead deposits. They can easily be picked out by a piece of safety wire or paper clip. The deposits are chunky in nature and are quite large. I can easily break up the chunks and it looks like dust/dirt. My best guess is that since my engine consumes about 1 quart in 4-6 hours, I'm seeing the additive in Camguard forming this deposit. By 10 hours, the lower plugs are full of deposits. Weird... They don't seem to affect how it runs. I have not changed oil brand, type or viscosity. Nor have I changed any other parameters. A quick look inside the cylinder reveals nothing unusual.
The only thing you don't mention for a variable is the type of operation--have you been flying at lower altitudes with a richer mixture, or doing a lot of pattern work? I do a lot of low-power loitering for hours on end and I lean aggressively up to a point, but I'm consistent--never had deposit problems, but I don't use Camguard either and I have never had an oil-related failure. Just food for thought. . .
 

Cujet

Thread starter
Messages
10,796
Location
Jupiter, Florida
No change in flying habits. I generally fly 7500 to 9500 feet, cross country. I don't fly lean of peak, as the Thunder Cardinal won't maintain altitude with reduced power. Generally peak power is used (which ain't much, 65% or less) Ed, since my last OC, I've not added any oil in 10 hours. It's about time to. So, I'll make sure to add CG at the proper ratio.
 
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Cujet

Thread starter
Messages
10,796
Location
Jupiter, Florida
I still have not flown enough to build up any deposits, about 2 hours total since plug cleaning. Ed, I have not forgotten your offer of deposit analysis. If I end up putting some hours in, I'll get you a sample right away. Stand by.
 
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