Proper Engine Break-in

PilotRPI

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PilotRPI
I'm looking at buying a plane, O-320, but I think they broke in their engine after an IRAN with Philips multi weight rather than straight weight or mineral oil. How big a deal is that? I think they have about a 100 hours on it now. Would any issues have surfaced or is this a non-issue?
 
Shouldn't be a problem. Most people use mineral oil to assist with the break-in, but Phillips multi-weight shouldn't be a problem, as long as they weren't putting Camguard or a similar additive into it. The proof of the pudding is in the eating, as they say, so are you having any issues with oil consumption, rapidly blackening oil, or CHT temperatures? If not, everything is probably fine. Worst case, just borescope the cylinders to be sure there's no glazing.
 
I'm looking at buying a plane, O-320, but I think they broke in their engine after an IRAN with Philips multi weight rather than straight weight or mineral oil. How big a deal is that? I think they have about a 100 hours on it now. Would any issues have surfaced or is this a non-issue?
The main issue is using the oil required by the shop performing the work to maintain any warranty coverage. Some shops use straight Philips XC and some shops don't.
 
Is a break in even necessary depending on how in depth the IRAN is.
 
Is a break in even necessary depending on how in depth the IRAN is.
For this one they had all new bearings, seals, honed cylinders, piston rings, so probably closer to an overhaul. I'll be doing a borescope for sure to check cylinder condition.
 
Shouldn't be a problem. Most people use mineral oil to assist with the break-in, but Phillips multi-weight shouldn't be a problem, as long as they weren't putting Camguard or a similar additive into it. The proof of the pudding is in the eating, as they say, so are you having any issues with oil consumption, rapidly blackening oil, or CHT temperatures? If not, everything is probably fine. Worst case, just borescope the cylinders to be sure there's no glazing.
Thank you. I'll be doing a borescope as part of a prebuy.
 
Is a break in even necessary depending on how in depth the IRAN is.
Any time you change rings or hone a cylinder it needs a run-in/break-in. If not the rings will not seat properly.
 
Having gone thru this on 2 different planes in the last four years.

Oil choice ain’t going to significantly impact engine life during break in.

Burning in an engine 1hr out a time is going to do more damage. So will long flights at less than 75% power.

If the shop doing the IRAN does a lot of engine work, that could be a positive. Shade tree A&P doing his first? I’d be more worried.

When considering a purchase, every engine is an unknown. Oil analyses from before, during, and after break in for a baby motor could be informative.
 
Any time you change rings or hone a cylinder it needs a run-in/break-in. If not the rings will not seat properly.
I knew that. Just didn't know to what extent this one was iran'd.
 
I knew that. Just didn't know to what extent this one was iran'd.
In the context of OP he mentioned "they broke in their engine." The only thing that gets broke-in is the rings/cylinder. Otherwise no "break-in" required.
 
BTW, Phillips makes a multi-weight mineral oil. There's a case of it on my workbench right now, that I intend to use for breaking in my overhauled engine.
 
BTW, Phillips makes a multi-weight mineral oil. There's a case of it on my workbench right now, that I intend to use for breaking in my overhauled engine.
Have had recent good luck on a break in using this oil. Think changed it at about 2 and 10 hours, then regular XC around 20 hours. Burn is about 1qt/20 hrs now which is same as last two big bore Continentals have broken in.

However, personally believe that high utilization early in engine life also helps - say 50 hours in first couple of months.
 
I used it (NOT the Victory version that has additives).
Since they also make a mineral multi-visc oil why not use that?

I did break in a Lyc and Cont turbo with regular XC but believe that was the recommendation from the manufacturer.
 
Since they also make a mineral multi-visc oil why not use that?

I did break in a Lyc and Cont turbo with regular XC but believe that was the recommendation from the manufacturer.

It was recommended by the overhaul shop.
 
Phillips is approved for break in. I've had some A&P's recommend it for break in.
From Lycoming themselves: https://www.lycoming.com/sites/default/files/attachments/Lycoming%20Reciprocating%20engine%20Break-In%20and%20Oil%20Consumption.pdf

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And from the referenced SI 1014: https://www.lycoming.com/sites/default/files/attachments/SI1014N%20Lubricating%20Oil%20Recommendations.pdf

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The opinions of Lycoming, gained through vast experience, trump the opinions of a mechanic.
 
The opinions of Lycoming, gained through vast experience, trump the opinions of a mechanic.

While I would agree, I think it is worth pointing out that the question of whether Phillips XC is acceptable for break in isn't simply a mechanic's opinion. Phillips states in their own literature that it can be used. So then the finger pointing can begin when something goes wrong. As was recommended up the thread a bit, I'd use whatever the overhauler tells me to use so they can't blame my choices on future problems.

My opinion, as a mechanic who has done quite a bit of research on the topic however, is in line with both Lycoming and Continental's recommendations. At least one oil tribologist agrees as well. It's almost like these companies and people did some research on it or something.
 
The opinions of Lycoming, gained through vast experience, trump the opinions of a mechanic.
If you had an engine overhauled by a shop that specified Phillips xc20w50 be used, would you use it or the opinion of Lycoming?
 
The opinions of Lycoming, gained through vast experience, trump the opinions of a mechanic.
If you had an engine overhauled by a shop that specified Phillips xc20w50 be used, would you use it or the opinion of Lycoming?
 
If you had an engine overhauled by a shop that specified Phillips xc20w50 be used, would you use it or the opinion of Lycoming?
I would ask that shop if they would rebuild that engine again, for free, if it did not break in properly and had high oil consumption. Make them back up their recommendations.
 
Apart from a well controlled study comparing the 2 oils, we're unlikely to have a definitive answer about which one if either is best. In some industries there is a bit of that's how we've always done it. I know in my industry there are many examples of what was once the gold standard being dethroned.
 
Apart from a well controlled study comparing the 2 oils, we're unlikely to have a definitive answer about which one if either is best. In some industries there is a bit of that's how we've always done it. I know in my industry there are many examples of what was once the gold standard being dethroned.
Lycoming wants a non-AD oil used for break-in for most engines because those oils don't have additives that reduce friction, and friction is what we want for proper ring seating. With those additives, the rings and cylinder walls are kept apart and don't cut each other until a good match is obtained; they just get polished, or "glazed' as we call it. There are open gaps left between the rings and cylinder in some areas, tiny but allowing leakage. That not only allows oil into the combustion chamber, it allows more combustion byproducts into the crankcase. Water and other corrosive stuff.

Now, some engines need those additives to survive. The O-320-H2AD needs them for cam and lifter lube, and turboed engine have higher combustion pressures that overcome the additives' separation of rings and cylinder walls. Once the rings are seated, the larger seating area will let the oil and additives keep those surfaces apart.

I always stuck to Lycoming's recommendations with new or overhauled engines. Most of them were Lyc factory overhauls, and I ran straight mineral for the first 50 hours. Those engines ran to TBO with compressions still in the high 70s and oil consumption very low, maybe a quart every 15 hours at most. Those cylinders and rings seated perfectly. I did the initial break-in flights, using the power settings described in SI 1427C, and forbade any pattern or upper air work for the first 15 hours. Cross-country stuff only.
 
I’ve rebuilt engines in both my planes in the last three years or so, and broke them both in with Phillips Cross Country achieving wonderful success. Mineral Oil for break in is old school. I’m pretty much an old school guy about some things, but not this.
 
If you're breaking in the engine, I would trust and follow the engine manufacturer's recommendations. If a mechanic or overhaul shop recommends something other than the engine manufacturer's recommendation, I would request something in writing stating the reason(s) for deviating. If they can't provide that, I would request something in writing stating that they will honor their warranty if the manufacturer's guidance is followed in lieu of their guidance (if it differs).

Phillips makes a "Type M" multi-weight oil which is a non-dispersant mineral oil for break-in. I used that when breaking in a cylinder earlier this year.
 
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