How much Camguard to add to O-470?

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MountainDude

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MountainDude
My mechanic did not have Camguard during the oil change recently, but I'd like to add it.
I have about 10 quarts of Phillips 20w50 in my O-470.
I plan to add Camguard, then fly the plane to mix it well.
How much Camguard should I add?
 
1.6 oz per qt of oil. You need 16 oz.

I use it for years now. I put it in once during oil change and don't add anymore until next oil change. I put 11oz in my 7 qt crankcase.
 
I add approx. 1.6oz to each quart of make up oil I carry with me to keep the CG/oil ratio remains the same until the next change.
 
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I add a pint with at oil change. No added Camguard until the next change. The prescripton from the mfgr is 5% Camguard for normal ops and they've told me to use 7% for storage.
 
1.6 ounce/quart is 47.4ml Camguard per quart of oil.

Each 16 oz bottle of CamGuard will treat 10 quarts of oil.

When I get a new case of Phillips X/C 20W50 oil, I pretreat each quart with CamGuard. Open the quart bottle and use a needleless 50 ml syringe to squirt the CamGuard into the bottle neck, reseal, and mark each treated bottle with a black felt-pen 'C'. That way I never need to think about it and the few quarts of oil I carry in the plane are ready to drink. And it's not rocket science, 45-50ml is fine.

This ensures all my make oil between oil changes has CamGuard.
 
The O-470 is a Continental, so does it have the cam below the engine? That may retain a layer of oil when not in use, less prone to corrosion compared to Lycomings having the cam on top. Consequently, less need of Camguard?
 
Just a data point - could be totally off...

When we had to repair the O-470 starter adapter I asked about Camguard after the first oil change. My mechanic indicated he was not a fan of using it - because of the starter adapter. Sorry I don't have a direct quote or resource. But I thought he had asked he engine rebuild shop (Bolduc) and they may have given that answer. Once again - sorry for no specific details. Or mabye he just meant the few low hour oil changes we did in succession to look for any more metals. Next time I chat with him I will see if I understood that right or not.
 
Camguard is dis-recommended for use during engine break-in. Wait until break-in is complete. I believe this also applies when you're breaking in a new cylinder on an existing engine.
 
I just remembered that I had read more after he had told me. I see discussions of O470 starter adapter with cam guard on beechtalk and back country forums.
 
MountainDude said:
Sinistar said:
Just a data point - could be totally off...

When we had to repair the O-470 starter adapter I asked about Camguard after the first oil change. My mechanic indicated he was not a fan of using it - because of the starter adapter. Sorry I don't have a direct quote or resource. But I thought he had asked he engine rebuild shop (Bolduc) and they may have given that answer. Once again - sorry for no specific details. Or mabye he just meant the few low hour oil changes we did in succession to look for any more metals. Next time I chat with him I will see if I understood that right or not.
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I know a ton of guys using Camguard in Continentals and have never heard anyone complain about starter adaptor slippage. If you want a stater adaptor problem? Use Aeroshell 15-50. A semi-synthetic oil is different than a mineral oil with a 5% additive. My Continental has had Camguard in it since well before it was approved to use it. Never a problem.
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How precise does the Camguard ratio need to be? Unless all of the borders of the sump are constructed at 90 degrees to each other and the engine sits level when the plane is on level ground, I'd imagine it'd be hard to be accurate about the amount of oil in the engine.

Sinistar said:
When we had to repair the O-470 starter adapter I asked about Camguard after the first oil change. My mechanic indicated he was not a fan of using it - because of the starter adapter.
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Can someone please educate me how a Continental starter adapter works and how it is affected by oil? I'm only familiar with automobiles and Lycomings where the starter engages with the flywheel (no oil involved).
 
Beechtalk is the place I read about Camguard starter adapter problems.
I believe the consensus was this was only an issue in worn adapters, and in cases of sub-optimal starting battery power.
 
asicer said:
Can someone please educate me how a Continental starter adapter works and how it is affected by oil? I'm only familiar with automobiles and Lycomings where the starter engages with the flywheel (no oil involved).
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Big Continentals use a friction drive (think wound spring with a shaft passing through it). It is bathed in motor oil and can slip under some circumstances, most often being when they're worn out. I haven't seen Camguard cause any starter adapter slippage but the motor oils with the Lycoming anti scuff additive in it has been blamed for causing some starter drives to slip. Aeroshell doesn't prohibit the use of their "plus" oils in these applications but they do recommend against using it in helicopters where the clutch is bathed in motor oil so that suggests to me that they know there is a problem with the additive in some applications.
 
asicer said:
How precise does the Camguard ratio need to be? Unless all of the borders of the sump are constructed at 90 degrees to each other and the engine sits level when the plane is on level ground, I'd imagine it'd be hard to be accurate about the amount of oil in the engine.
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Well, you drain out all the oil and then put X quarts in, you KNOW you have X quarts in the engine.
 
Pinecone said:
Well, you drain out all the oil and then put X quarts in, you KNOW you have X quarts in the engine.
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Sure, as long as the engine has been sitting long enough for all the oil to drip back down into the pan, before you drain it.
Also, following @Domenick 's advice to add Camguard to each oil quart before using it, ensures you have an accurate blend.
 
Pinecone said:
Well, you drain out all the oil and then put X quarts in, you KNOW you have X quarts in the engine.
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Yes, but that brings us back to my first question: how precise does the Camguard ratio need to be?
 
put a pint in.....and that's it. I don't bother when adding make up oil.
 
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asicer said:
Yes, but that brings us back to my first question: how precise does the Camguard ratio need to be?
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Camguard doesn't provide an error range. They simply say mix at 5%. Since any additive displaces oil that would otherwise be there, and the engine can run on pure oil without any Camguard, common sense says aim for 5% yet err on the side of lower ratios, than higher.
That is, not enough Camguard may reduce any benefit but won't cause harm. Too much Camguard could actually cause harm by changing the oil viscosity or other attributes.
 
Adding a extra few ounces of Cam Guard to 6 - 10 quarts of oil is not going to change the viscosity or other attributes.
 
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