Type of oil recommended for O-300 engine??

juasiel123 · Post by **juasiel123** » Sun Mar 25, 2007 4:43 pm

Hi.. I recently overhauled my engine from my C-170 due to engine damage because of loss of oil pressure in flight. Which ended in a mayday, mayday... (you know what I mean).

Fortunately nothing happened and I landed safely. The result of the engine inspection resulted on a spoiled oil pump.

The mechanic recommended a replacement of the oil I am using on it, and this is the aeroshell whit the red tag on it, since this product has detergent on it's contents. Which does not allow to flow the oil as it's supposed to, since the detergent makes some kind of plug inside the engine where flows the oil.

I don't know if what the mechanic told me it is completely true, but I consider it and started a search for a better brand and type of oil to avoid another loss of oil pressure on my engine.

He also said to keep using the aeroshell oil until I reach the 100 hrs. of breaking in, and then replace the oil whit another whit out detergent.

Could you please suggest me any other brand of oil that does not have detergent in its contents???
I would really appreciate any comments!!

Thank's

Juasiel

Tom Downey · Post by **Tom Downey** » Sun Mar 25, 2007 7:43 pm

Phillips 20W50

mit · Post by **mit** » Sun Mar 25, 2007 9:40 pm

Post by **GAHorn** » Mon Mar 26, 2007 12:13 am

Your mechanic is recommending a "non-additive" oil. It is NOT a "detergent" oil. Your mechanic is correct. For a new engine, do NOT use "W" rated oils such as "W100". Use W100 after the engine is broken in.

Tom Downey · Post by **Tom Downey** » Mon Mar 26, 2007 5:55 am

gahorn wrote:Your mechanic is recommending a "non-additive" oil. It is NOT a "detergent" oil. Your mechanic is correct. For a new engine, do NOT use "W" rated oils such as "W100". Use W100 after the engine is broken in.

ECI says 20W50 from day one to TBO, They say there is no advantage to using a NON D oil for break in.

I have 6 sets of ECI running in Customers aircraft following ECI reccomendations and have had no problems.

Oil consumption was stable at 5 hours after installation.

see their web page under oil talk for dummies.

http://eci2fly.com/pdf/BI07-2005.pdf#pa ... rks&page=3

Post by **GAHorn** » Mon Mar 26, 2007 2:31 pm

This topic comes up from time to time, and it sometimes provokes strong feelings for unworthy reasons, in my opinion.
The "old timers" in this industry discovered that additive oils sometimes prevented proper break-in of cylinders due to "glazing" of cylinder walls. This was probably due to insufficient friction to allow the rings/cyl. walls to polish themselves to each other. Once the walls became glazed, the rings/cylinders would never properly seat and the engine would become an "oil burner". The only fix was an expensive partial tear-down of that engine...the removal of the cylinders and further repair work.
A much higher success rate...virtually 100% , was achieved when the procedure with non-additive oil was used. There is no disadvantage to using non-additive oil, therefore it became the de facto standard recommendation/method.

The oil industry competition between brands is keen. AeroShell has been fortunate in having few developmental problems with a good product. Phillips' attempt to "break in" (sorry for the pun) met with some difficulty when one of their earlier products was found to contribute to stuck valves, and a later one was found to cause excessive corrosion (according to some reports from non-related parties.) Phillips went to considerable expense to regain an entrance to the market, and they now have a worthy product in their multi-grade oil.

Company marketing departments are relied upon and heavily funded when such mistakes occur as Phillips experienced with their aero oil. One method used is to find a way to re-introduce the product to the market. The popular method used by Phillips (and others) has been to make their product available, either free or at large discoun, to OEM and re-bulders of engines and engine products. This was done by Phillips at one time, when new Cessnas were delivered from the factory with that oil. If a mfr, such can get support from the oil company in return to recommending that product to their customers, or even better....by inclusion in new-product recommendations, ...then it would be a good method to get AeroShell users to switch brands. Once a customer selects a particular brand of oil, it's more likely the customer will stay with that brand. It's a good Phillips strategy.

It may even work well with ECI's cylinder mfr'g process. But that does not make it the best choice for all the rest of the industry. And unless ECI is going to invalidate their warranty for the use of a different, approved aero engine oil, (and their literature does not make any claim that the use of another aero oil is a problem) then it makes little sense to many mechanics who have a lifetime of experience using non-additive oils successfully (and a similar experience of failures using additive oils) to change their recommendations to their customers.

1SeventyZ · Post by **1SeventyZ** » Mon Mar 26, 2007 9:22 pm

I second the Philips 20w50...although with the few hours I've put on my engine so far, bacon grease probably would have done just as good.

The IA at our local maintence shop runs it in his rental fleet and says he's gotten beyond TBO on all of them. I'm not sure if that's a testament to the oil or not, but it's something.

russfarris · Post by **russfarris** » Tue Mar 27, 2007 4:04 am

I've used nothing but Phillips 20w-50 since my overhaul with new Superior's Milleneum cylinders four years and 400 hours ago. Oil consumption settled down in less than five hours, and consistently I go
15 to 20 hours before I have to add a quart. It works for me...Russ Farris

flyer170 · Post by **flyer170** » Tue Mar 27, 2007 1:56 pm

I use Phillips 20X50 and have been satisfied.
Bob

william halford · Post by **william halford** » Fri Mar 30, 2007 11:46 am

Break in oil is not really required today like it was 25-30 yr. ago. The oil today is of better quality. I have talked to Mobile along with Aeroshell at all the trade shows, both have said there is no reason what so ever to use mineral oil (or Dinosaur oil) during the break in procedure. But (there is always a But) if you O/H your engine yourself and signed the logbook follow there procedure. But if an â€œOld Timerâ€ did your O/H & he said install mineral oil for the first 50 hrs they suggest doing it his way our the warranty could be voided.

As far as 20w50 you canâ€™t beat it in the winter after a cold night, it sure fells good to see that oil pressure rise in less than 10-15 seconds after start up. Gary

robert.p.bowen · Post by **robert.p.bowen** » Fri Mar 30, 2007 12:25 pm

One thing to remember on a newly overhauled engine is to NOT use an oil during break-in that has antiwear additives in it. Those oils are Exxon Elite, Aeroshell 80+ or 100+, and Aeroshell 15W-50. I concur there is no technical reason to use mineral oils these days, and certainly not for 50 hours. TCM reps. have told me if you use mineral oil for break-in, get it out as soon as CHT's have come down and oil consumption has stabilized. This is because mineral oil has no anticorrosion additives, and the first hours after overhaul are when the engine is most vulnerable to rust.

Phillips 20W-50 and Aeroshell W100 work fine as a break-in oil, and can be used for the entire engine run if you wish, particularly if the engine is run frequently. If the airplane is used irregularly, you may wish to consider one of the antiwear and anticorrosion oils, which are the four first listed above.

HA · Post by HA » Fri Mar 30, 2007 3:08 pm

hey Juasiel, did you switch from running straight mineral oil (no detergent) for most of your engine's life, to AD oil (detergent) before you had the oil pressure problems?

that might be what your mechanic is talking about. if the engine was run for a long time with straight mineral oil then there could have been a lot of sludge built up inside the engine. switching to AD (detergent) oil would cause some of those deposits to be loosened and they could block an oil passage somewhere. usually that results in a spun rod bearing first.

I used to see some pretty gunked up engines back when people were using mineral oil, while with the modern oils with the additives (which act to keep the normal combustion products that get into the oil between changes, in suspension in the oil so that they drain out when the oil is changed) the engines are much cleaner now.

IMHO as a guy who used to do all of our company's engines, the big reason to use straight mineral oil for break-in is if you have chrome cylinders, which will "glaze" and not seat with the rings if your oil is "too good". otherwise I'd stick with any modern AD oil. I personally use Aeroshell 15W50 because I don't fly this airplane enough and so I want the antiwear and anti-corrosion additives that it has.

good luck with your newly overhauled engine.

Tom Downey · Post by **Tom Downey** » Sat Mar 31, 2007 1:58 am

HA wrote:hey Juasiel, did you switch from running straight mineral oil (no detergent) for most of your engine's life, to AD oil (detergent) before you had the oil pressure problems?

Please note,,,,,,,,,,, the "D" in AD oils doesn't mean detergent.

the "D" Means despersent, IOW it has the ability to carry dirt and foreign material to the filter

juasiel123 · Post by **juasiel123** » Sat Mar 31, 2007 2:03 am

Actually HA... I was usin the AD oil at the moment of the loss of oil preasure causing the engine failure. Thank's for the comments, have been very helpfull!!

HA wrote:hey Juasiel, did you switch from running straight mineral oil (no detergent) for most of your engine's life, to AD oil (detergent) before you had the oil pressure problems?

that might be what your mechanic is talking about. if the engine was run for a long time with straight mineral oil then there could have been a lot of sludge built up inside the engine. switching to AD (detergent) oil would cause some of those deposits to be loosened and they could block an oil passage somewhere. usually that results in a spun rod bearing first.

I used to see some pretty gunked up engines back when people were using mineral oil, while with the modern oils with the additives (which act to keep the normal combustion products that get into the oil between changes, in suspension in the oil so that they drain out when the oil is changed) the engines are much cleaner now.

IMHO as a guy who used to do all of our company's engines, the big reason to use straight mineral oil for break-in is if you have chrome cylinders, which will "glaze" and not seat with the rings if your oil is "too good". otherwise I'd stick with any modern AD oil. I personally use Aeroshell 15W50 because I don't fly this airplane enough and so I want the antiwear and anti-corrosion additives that it has.

good luck with your newly overhauled engine.

Post by **GAHorn** » Mon Apr 02, 2007 3:34 am

robert.p.bowen wrote:... and the first hours after overhaul are when the engine is most vulnerable to rust. ....

Why would the first hours be more likely to contribute to rust than any other time in an engine's lifetime?

(And if rust were the concern in an un-preserved engine which did not receive regular operations, then I'd recommend a single-grade oil and to stay away from the "plus" oils which might have phosphates.)