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Camillo

Well Known Member
Hi.
I am about to place an order to Spruce and was looking ahead buying some engine break-in oil.

I read a few documents and threads and found that for the break-in period a mineral oil should be used. That may be EXXON 20W-50 http://www.aircraftspruce.com/catalog/eppages/exxonoils.php or 08-05410 Aeroshell mineral oil (not further detailed...) http://www.aircraftspruce.com/catalog/eppages/aeroshelloils.php

While still deciding which of the previous oils I can buy, I read Lycoming Service instruction 1014M which has a CAUTION stating:

"AIRCRAFT MANUFACTURERS MAY ADD APPROVED PRESERVATIVE LUBRICATING OIL TO PROTECT NEW ENGINES FROM RUST AND CORROSION AT THE TIME THE AIRCRAFT LEAVES THE FACTORY. THIS PRESERVATIVE OIL MUST BE REMOVED AT END OF THE FIRST 25 HOURS OF OPERATION. WHEN ADDING OIL DURING THE PERIOD PRESERVATIVE OIL IS IN THE ENGINE, USE ONLY AVIATION GRADE STRAIGHT MINERAL OIL OR ASHLESS DISPERSANT OIL, AS REQUIRED, OF THE VISCOSITY DESIRED"

Does that mean that the preservative oil is OK for breaking-in the engine? Is it a mineral oil?

Thanks.
Camillo
 
Definately want some experienced people to weigh in on this, but I was helping break in a TSIO 520 once and we used shell mineral oil (I think the aeroshell 100). I think it was for the first 20 hrs or maybe 10. It seemed real strange to me. It was maybe 40 F outside and that stuff had the consistency of pudding. After the period we drained the oil, sent in a sample, cut the filter then filled it back up with standard shell. Although now I think I would rather use the exxon or castrol oils. From everything I've read they seem superior to the aero shell. But thats just my opinion
 
Camillo said:
Hi.
Does that mean that the preservative oil is OK for breaking-in the engine? Is it a mineral oil?
Click to expand...

No, You'll find that there is very little oil in there. Remove the bottom plugs & oil drain plug to drain what's there. In the meantime, there will be residual preservative oil in the engine. That will mix with the break-in oil, and that's what you'll remove on the first oil change.

L.Adamson --- RV6A
 
jtop said:
Definately want some experienced people to weigh in on this, but I was helping break in a TSIO 520 once and we used shell mineral oil (I think the aeroshell 100). I think it was for the first 20 hrs or maybe 10. It seemed real strange to me. It was maybe 40 F outside and that stuff had the consistency of pudding. After the period we drained the oil, sent in a sample, cut the filter then filled it back up with standard shell. Although now I think I would rather use the exxon or castrol oils. From everything I've read they seem superior to the aero shell. But thats just my opinion
Click to expand...

I wouldn't run Aeroshell 100 mineral oil in cold temps. either. I used it, but switched before winter months.
 
You need to run "straight" oil - as said above that is Aeroshell 100 or 80 (or equivalent from other companies) - for the first 50 hours or so. If the temperature isn't above 70 deg I'd use 80. The straight oil will ensure the cylinders break in properly so that your oil consumption reduces to 1 qt every 10 or 15 hours. If this procedure is not done properly your oil consumption will remain high throughout the life of the engine. You should also ensure the CHTs are kept as cool as possible. You will burn upto a qt an hour initially, but that should drop quickly.

A lot has been written here about initial break in, it is important you do it properly. Change the oil and filter after 10 hours, using straight oil. Change again after another 25 hours, if your oil consumption is already stable you could consider going to a W oil (ashless dispersant) or a multigrade (like the Exxon 20W-50 you were going to buy) - other wise go with the straight oil again for another 25 hours. The reason for using straight oil initially is that the other oils are too good and prevent the cylinders breaking in properly.

Pete
 
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Sorry, but the Exxon 20W-50 is advertised as a break-in oil. Isn't it right?
Shall I go with the Aeroshell mineral oil instead? Spruce doesn't clarify is it is 80 or 100...
Thanks.
 
I'd recommend the Phillips 20W-50 Type "M" oil for breaking in a new engine.

The multiweight means it will flow exceptionally well at cold startup temperature, and the mineral means it's the right stuff for a fresh engine break-in. The type "M" doesn't have the ashless dispersant like the Phillips X/C 20w50 does.

Read about it here:
http://www.phillips66aviation.com/products/type_m_20-50.aspx
 
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