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Phillips 20w50

C-FAH Q

Well Known Member
Can Phillips 20w50 be used as a break in oil when replacing one cylinder? Or should it be changed to a mineral oil?
 
ECI recommends it for breaking in with their cylinders.

I like to use Phillips Type M 20W-50M mineral oil for break-in on my engines.

Yes I am presently running 4 ECI Steel cylinders. Broke in on M 20W-50 for about 25-hours then switched to X/C 20W-50. After 400 hours of operation, I do not add oil between 40-45 hour oil changes. I would let it go up to 50 hours as recommended by Lycoming but do not like to run below 5-quarts. I fill with 7-quarts and a new filter. It reads just over 6 on the stick.
 
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HI, Is it a steel or chrome cylinder? I'd go Mineral for either but definetly for a chrome cylinder.
Doug.
 
SacSky states that Mineral oil will char at a lower temperature than compounded oil.
Breaking in a new engine is when the highest temperatures happen. new parts wearing in 'marrying' as the old machinist would say.
Also, the exhaust ports don't have an insulating coating of carbon yet.
Oil temps are high at the gauge, but higher still in local areas like the heads around the exhaust valve.
I know its Heresy to say, but I'm not in favor of high power break in with mineral oil.
I'm more comfortable with Philips X/C 20-50 and a more modest break in.
That's just me.
 
20-50

I topped my angle valve last year and used Phillips 20-50 to break it in. I read many articles and concluded that mineral oil is like gynecology, old wives tail. Talked to a lot of knowledgable engine guru's that said run it hard on regular oil. After 200 hours my consumption is about a quart every 18-20 hours.

Blaze away.
 
X/C 20W-50

X/C 20W-50 is 97% mineral oil and 3% ashless dispersant by volume. The AD does not enhance lubricity and its job is to capture wear metal and debris into the oil film and carry it to the filter. Break-in is when you generate the most wear metal and debris so the AD is essential at that time. No need to use the type M for break-in in my mind.

Grub
 
I know its Heresy to say, but I'm not in favor of high power break in with mineral oil.
I'm more comfortable with Philips X/C 20-50 and a more modest break in.
That's just me.

I topped my angle valve last year and used Phillips 20-50 to break it in. I read many articles and concluded that mineral oil is like gynecology, old wives tail. Talked to a lot of knowledgable engine guru's that said run it hard on regular oil. After 200 hours my consumption is about a quart every 18-20 hours.

Philips X/C 20W-50 is mineral oil (says so right on the side of the bottle) and is the primary break in oil recommended by Philips. The difference b/w it and Type M is that the Type M doesn't have the AD added.

http://www.phillips66aviation.com/lub_matrix.aspx
 
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Philips X/C 20W-50 is mineral oil (says so right on the side of the bottle) and is the primary break in oil recommended by Philips. The difference b/w it and Type M is that the Type M doesn't have the AD added.

http://www.phillips66aviation.com/lub_matrix.aspx

You are entirely correct, however the term has been misused for a very long time by a great many people. "Mineral oil" in the context of engine lubricants simply means the product is petroleum based, in contrast to a synthetic product. The inclusion or exclusion of of ashless dispersant (AD) additives is a separate issue. ECI, Mike Busch and others believe that AD oils are fine for engine break-in, while an opposing group will advise you that AD oils should not be used for break-in. Unforntunately, this latter viewpoint is commonly communicated as "only use mineral oil" or "only use straight mineral oil" which confuses the issue.

erich
 
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