Engine wasn’t broken in with mineral oil, how shafted are we?

[Half Fast]

I've told this story on PoA before, but cannot resist telling it here, given direct reference. It is my favorite airplane story.

A close friend of mine bought a Cherokee 180. When he replaced the interior, the backside of the panels was nasty. Backstory from the previous owner:

One of his uncles passed away, and requested his ashes be scattered over Tampa Bay. He and his wife flew over the bay with the ashes in a bag. They opened the small side vent window and placed the mouth of the bag over it. The bag inflated, then exploded. Instant IMC in the cockpit, everyone gagging, ashes in their eyes, mouth, hair, etc.

“We miss him, but there’s a little bit of Uncle Joe in all of us...”

 

[pfarber]

Except those number are max power. You calculate based on what power settings you were using.

I posted max HP. I guess I'm gonna have to maths it outs for you'all

SB oil consumption formula:
0.006 x BHP x 4 ÷ 7.4

.006 * (230 * .75) X 4 + 7.4 = .55qt/hr (let assume 75% power for cruise for the lowest HP 0-540)

OP reports .25 to .5 STILL UNDER LYCOMINGS FIELD OVERHAUL SPECS. Remember serviceable specs are not NEW. The motor can be loosy-goosy becuse it could have been done to serviceable specs, not new. Again, OP isn't giving the details.

OP never said what model o-540s he's running.

Lets see what OTHER PoA members think:

How much oil burn is too much?

I realize that oil consumption may vary quite a bit, but I want to get an idea of what the acceptable range is and when (absent any other signs of a problem) I should start to care? Lycoming O-540-B4-B5, currently I usually add a quart maybe every 4 or 5 hours of flight time, give or take...

www.pilotsofamerica.com

"That doesn’t seem unreasonable for an o-540. I fly and maintain several airplanes with 540s (a total of 7 engines) and they all seem to consume a quart of oil in 4-8 hours."

 

[jbarrass]

Borescoping is cheap, easy, and will answer the question. No way I'd be pulling cylinders without knowing what problem I'm fixing. Way too many parts get changed to "let's see if this works"

 

[Racerx]

I posted max HP. I guess I'm gonna have to maths it outs for you'all

SB oil consumption formula:
0.006 x BHP x 4 ÷ 7.4

.006 * (230 * .75) X 4 + 7.4 = .55qt/hr (let assume 75% power for cruise for the lowest HP 0-540)

OP reports .25 to .5 STILL UNDER LYCOMINGS FIELD OVERHAUL SPECS. Remember serviceable specs are not NEW. The motor can be loosy-goosy becuse it could have been done to serviceable specs, not new. Again, OP isn't giving the details.

OP never said what model o-540s he's running.

Lets see what OTHER PoA members think:

How much oil burn is too much?

I realize that oil consumption may vary quite a bit, but I want to get an idea of what the acceptable range is and when (absent any other signs of a problem) I should start to care? Lycoming O-540-B4-B5, currently I usually add a quart maybe every 4 or 5 hours of flight time, give or take...

www.pilotsofamerica.com

"That doesn’t seem unreasonable for an o-540. I fly and maintain several airplanes with 540s (a total of 7 engines) and they all seem to consume a quart of oil in 4-8 hours."

Just pointing out that consumption is based on actual power settings. Not max rated.

While within spec. It's BARELY within spec. And 1qt every 2 hours is double the consumption you report. Probably on engines with more than 150 hours. What's the harm in throwing a scope down there?

OP, how's that first mag check?

 

[Initial Fix]

Oh boy.

I just broke in a new Io-520 this summer. Mineral oil changed at 25, then regular oil at 50 hours. Oil consumption was steady after a few hours. Typical full power break in procedure the first hour, with my IA sitting next to me on the first flight flight.

I have my fingers crossed for you. But the information so far is pointing to pulling and honing cylinders.

 

[kyleb]

I put 8 quarts of oil and a pint of camguard in my 540 at each oil change. I don't need to add any oil between oil changes. I'd be very bothered by an oil burn that approached 1/2 quart an hour UNLESS the engine was being over-filled and blowing the oil out the breather.

 

[WDD]

Good point. Each engine has its own unique oil level, above which it will blow it out the breather. I assume the OP is filling the engine up to but not over that engine’s specific level.

 

[Dana]

Good point. Each engine has its own unique oil level, above which it will blow it out the breather. I assume the OP is filling the engine up to but not over that engine’s specific level.

And that specific level may or may not be the maximum marked on the dipstick.

 

[Motor6]

On my O-540 I add 1 quart when it drops to 8. Anything over 9 and I’d have burn (or spit down the belly) rates like OP till it got down to 9.

 

[WDD]

Same for my Continental 0470 R

Book says I can fill to 12, but anything over 9 and it goes out the breather. I add a quart when it gets to 8.

 

[Dana]

And same with my O-290; it held 6 but I kept it between 4-5 or I'd be cleaning a lot of oil off the belly of the plane.

 

[kyleb]

If the OP is still following this thread, it would be interesting to understand how much oil he's putting in his -540 and if he's given it time to stabilize at some level, or if the oil level just continues to drop regardless of how much oil its holding.

 

[pfarber]

Oh boy.

I just broke in a new Io-520 this summer. Mineral oil changed at 25, then regular oil at 50 hours. Oil consumption was steady after a few hours. Typical full power break in procedure the first hour, with my IA sitting next to me on the first flight flight.

I have my fingers crossed for you. But the information so far is pointing to pulling and honing cylinders.

Nothing OP has stated leads to pulling all 6 cylinders.

Oil consumption is within manufacturers specs.
OP never told us what the plugs looked like
OP never told us if the engine runs rough/fails mag check
OP didn't 'scope the cylinders
OP didn't state compression
OP didn't state if the motor made max RPM on the ground
OP didn't state exactly how much oil was added at refill (could be as simple as overfilling the case)

The key point is that the break in is complete (per the SB) when OIL CONSUMPTION STABILIZES. If OP is burning a consistent .25 qts and hour then that would indicate break in has done its job.

If all (or even most) of the above checks are OK then OP's just got a leaky motor. Nothing is pointing to glazed cylinders or rings not seating.

It is 100% OPs prerogative to have the work done just to lower a 'percieved' high oil burn rate... but nothing kills a motor faster than letting an AnP attack a non-issue with tools.

OP did ask for advice and now the checkbook is in their court.

 

[pfarber]

Also also OP never stated what cylinders he has.

Is there a nice orange stripe on the cylinders?

 

[Clip4]

1/4th quart per hour doesn't sound too bad, esp on an o-540. as others have said, i'd just borescope the cylinders to get an idea if it worked or not.

I don’t know what O-540 Lycoming engines you fly, but a quart every 4 hours is excessive.

 

[Dan Thomas]

The key point is that the break in is complete (per the SB) when OIL CONSUMPTION STABILIZES. If OP is burning a consistent .25 qts and hour then that would indicate break in has done its job.

It would indicate that break-in-in is definitely lacking. We had an O-540 in the R182, and the oil consumption was far, far better that .25 quarts per hour. We added a quart maybe every 10 or 12 hours, at most.

In Post #46 kyleB says this:
I put 8 quarts of oil and a pint of camguard in my 540 at each oil change. I don't need to add any oil between oil changes.

That alone says that something is very wrong with the OP's engine unless he's overfilling it, yet he's been flying that airplane on the pre-overhauled engine and would know where the level should be.

If all (or even most) of the above checks are OK then OP's just got a leaky motor. Nothing is pointing to glazed cylinders or rings not seating.

In your limited experience, of course. Once you get a few more years in this business, you'll think differently.

Maybe. Some people resist learning.

I don’t know what O-540 Lycoming engines you fly, but a quart every 4 hours is excessive.

The Lycoming Operator's manual lists acceptable consumption levels as high as nearly a quart an hour. But that would be taken by a wise operator to apply to a tired old engine, not a freshly-overhauled engine.

The Gipsy Major engine in my Auster burned a quart of Aeroshell W100 per hour. Changing to a Texaco aviation oil (does it still exist?) cut that to half a quart an hour. When I dismantled the engine I found massive piston-to-cylinder clearances (like .100", at least 20 times normal) and badly worn rings. The engine had no induction filter, never did, and it had better than 600 hours on it. The TBO on those ancient engines was about 600 hours.

A freshly-overhauled Lyc O-540 has NO business burning a quart in four hours. None.

 

[Daleandee]

The Lycoming Operator's manual lists acceptable consumption levels as high as nearly a quart an hour. But that would be taken by a wise operator to apply to a tired old engine, not a freshly-overhauled engine.

... and there it is!

 

[Southpaw]

Years ago my dad’s cousin bought a new 1955 Chevy with the 265 v-8. It was returned to the dealer by former owner for excess oil consumption. Dad’s cousin was a mechanic at the dealer ship and bought the car for cheap.
Took it home and sprinkled a box of BonAmy in carb. Stopped using oil and ran a long time with very little oil consumption.
Not suggesting to do this with aircraft engine , but it worked in a auto engine

 

[FPK1]

For the vast majority of Lycoming and Continental engines, using "Plus" oil during break-in can cause expensive damage by preventing the piston rings from seating properly.

AeroShell W100 Plus contains advanced anti-wear and anti-scuffing additives. These make the oil "too slippery." If you use this oil, the rings may never wear into the cylinders properly, leading to cylinder glazing.

 

[Philip98]

If the OP is still following this thread, it would be interesting to understand how much oil he's putting in his -540 and if he's given it time to stabilize at some level, or if the oil level just continues to drop regardless of how much oil its holding.

Yes, I am still following. Was leaving Japan when I posted and just arrived home.

For reference, pre-overhaul, the engine sat at 9 quarts and was happy. I still fill it to there through the other pilots fill it less. I let it drop to 6 once to see if it gets better before I got scared and filled it back up to 9. Pretty sure this means there is something worse as play.

I like the theory of the cylinder glazing as much as my wallet doesn’t. One of the other pilots disagrees with me on what oil was used during the break in. He says an oil without anti-wear additives was used, we will need to go hunting through receipts and figure out for certain what oil it was. I know for certain it wasn’t the recommended by Lycoming oil as I have a text from the mechanic telling me that he used a different oil.

I will note that our break in period wasn’t super smooth. On the first flight (which I did), I only flew for maybe 5 minutes because the fuel line wasn’t fastened and I started having engine surging, as the fuel supply was interrupted and resumed, so I made an immediate emergency return to the airport.

The second flight was by another pilot, he had to return after like three hours due to a drop in oil pressure. That was because the overhaul shop didn’t torque on the oil return line from the oil cooler to the right torque and it vibrated to finger loose. The engine lost so much oil that it only barely had more left then what Lycoming said the minimum was before needing an IRAN/overhaul.

Overall, it’s been a terrible experience. The engine runs normally however besides one cylinder being colder and the high oil consumption. Oil filter and oil analysis (we send all oil samples out) are also normal.

 

[ateamer]

And that specific level may or may not be the maximum marked on the dipstick.

This. The O-360 in my RV-8 was happiest at 5.5 quarts. When I filled it with 6, it’d go down to 5.5 within an hour, and then stay there for 10+ hours. The -360 in my 175 settles at 6; anything above that will be on the belly in short order.

 

[Half Fast]

Does cylinder glazing cause any problems other than high oil consumption?

 

[Lama1125]

Yes, I am still following. Was leaving Japan when I posted and just arrived home.

For reference, pre-overhaul, the engine sat at 9 quarts and was happy. I still fill it to there through the other pilots fill it less. I let it drop to 6 once to see if it gets better before I got scared and filled it back up to 9. Pretty sure this means there is something worse as play.

I like the theory of the cylinder glazing as much as my wallet doesn’t. One of the other pilots disagrees with me on what oil was used during the break in. He says an oil without anti-wear additives was used, we will need to go hunting through receipts and figure out for certain what oil it was. I know for certain it wasn’t the recommended by Lycoming oil as I have a text from the mechanic telling me that he used a different oil.

I will note that our break in period wasn’t super smooth. On the first flight (which I did), I only flew for maybe 5 minutes because the fuel line wasn’t fastened and I started having engine surging, as the fuel supply was interrupted and resumed, so I made an immediate emergency return to the airport.

The second flight was by another pilot, he had to return after like three hours due to a drop in oil pressure. That was because the overhaul shop didn’t torque on the oil return line from the oil cooler to the right torque and it vibrated to finger loose. The engine lost so much oil that it only barely had more left then what Lycoming said the minimum was before needing an IRAN/overhaul.

Overall, it’s been a terrible experience. The engine runs normally however besides one cylinder being colder and the high oil consumption. Oil filter and oil analysis (we send all oil samples out) are also normal.

Have you looked at the spark plugs and noticed them being black or wet? Is the engine rough while idling? Has anyone noticed thin white smoke at any point during running? How much smoke, if any, comes out of the tail pipe when it is first started? Is your belly wet with oil or is there a white line just aft of the exhaust?

 

[Bell206]

He says an oil without anti-wear additives was used,

I know for certain it wasn’t the recommended by Lycoming oil

Here is the Lycoming bulletin that references what oil to use for break-in. If as noted no anti-wear additives were used like Aeroshell 100, then the oil was not your problem. Lycoming's recommendation is by oil type not brand.

I will note that our break in period wasn’t super smooth.

This can actually have a greater effect on cylinder break-in then oil type. The loss of oil event during the 2nd break-in flight should have been dealt with a bit deeper, but can't go back at this point with 150 hrs on it. Is the engine still under warranty from the shop? If so, I think a call to them would be prudent to get their input on the matter. Be sure to explain what transpired during the break-in and verify the oil type so they can offer the best advice.

 

[cowman]

So here's my question; what's the worst case scenario if OP just keeps flying it as is?

Unless I'm mistaken the concern would be increasing oil consumption and/or loss of compression right? If either of those things occur then OP will need a hone & re-ring job... but that might not happen. It might continue consuming oil at a fairly reasonable rate and have good compression.... maybe even over time the rings seat in a little better. Seems to me that the only risk is eventually having the same procedure later on vs doing it preventatively now.

Again unless I'm missing something here it seems to me the answer is straightforward. Keep on flying but keep monitoring the consumption and watch the compression, maybe do an oil analysis. If there's no risk of sudden catastrophic failure why put all that money into a procedure that may not be necessary?

 

[Dan Thomas]

Again unless I'm missing something here it seems to me the answer is straightforward. Keep on flying but keep monitoring the consumption and watch the compression, maybe do an oil analysis. If there's no risk of sudden catastrophic failure why put all that money into a procedure that may not be necessary?

If the oil consumption is high, so is the blowby. That sends lots of carbon, moisture and other contaminants into the crankcase, where it all accumulates as sludge and varnish and carbon, and causes serious corrosion. Keep on flying it and you might find that it's not repairable once you decide to fix it. Now you're buying a new engine, outright.

Wishful thinking never fixed anything properly.

 

[Dan Thomas]

why not trust the mechanic? why jump to automatically thinking you're screwed? I'd worry about it in 2000 hours or so

There is incompetence in any field, and there are incompetent mechanics. We hear about them often enough on POA.

I will note that our break in period wasn’t super smooth. On the first flight (which I did), I only flew for maybe 5 minutes because the fuel line wasn’t fastened and I started having engine surging, as the fuel supply was interrupted and resumed, so I made an immediate emergency return to the airport.

The second flight was by another pilot, he had to return after like three hours due to a drop in oil pressure. That was because the overhaul shop didn’t torque on the oil return line from the oil cooler to the right torque and it vibrated to finger loose. The engine lost so much oil that it only barely had more left then what Lycoming said the minimum was before needing an IRAN/overhaul.

 

[flyingcheesehead]

This can actually have a greater effect on cylinder break-in then oil type. The loss of oil event during the 2nd break-in flight should have been dealt with a bit deeper, but can't go back at this point with 150 hrs on it. Is the engine still under warranty from the shop? If so, I think a call to them would be prudent to get their input on the matter. Be sure to explain what transpired during the break-in and verify the oil type so they can offer the best advice.

It sounds like it was a field overhaul by the same mechanic that didn't put mineral oil in it. And given the issues they experienced (quoted by Dan above), the whole overhaul is suspect.

 

[Bell206]

It sounds like it was a field overhaul by the same mechanic that didn't put mineral oil in it. And given the issues they experienced (quoted by Dan above), the whole overhaul is suspect.

I believe if you read closer, the mechanic installed an engine OH'd by a shop (who also left an oil loose) and that another pilot told the OP " an oil without anti-wear additives was used" for the break-in. So the only suspect at the moment is if the non-standard break-in procedure used was an issue and to verify what oil type was used.

 

[Philip98]

I believe if you read closer, the mechanic installed an engine OH'd by a shop (who also left an oil loose) and that another pilot told the OP " an oil without anti-wear additives was used" for the break-in. So the only suspect at the moment is if the non-standard break-in procedure used was an issue and to verify what oil type was used.

Yes, the mechanic was not the one that did a field overhaul. Normally, we would have not done a field overhaul but at the time, we thought the engine only needed minor work then we found out the engine was shot and at that point it was already taken apart at the engine shop. Normally we would send the engine out to Lycoming.

At any rate, the engine is getting looked at again. Hopefully this winter… Will report back the findings.

 

[flyingcheesehead]

I believe if you read closer, the mechanic installed an engine OH'd by a shop (who also left an oil loose) and that another pilot told the OP " an oil without anti-wear additives was used" for the break-in. So the only suspect at the moment is if the non-standard break-in procedure used was an issue and to verify what oil type was used.

Ah, I was going by the "field overhaul" from the OP, but I do see the last post that mentions a shop now.

I wouldn't be using either the shop or the mechanic again if things are described accurately here...

 

[Racerx]

So we it might not be glazing. What would a broken ring look like with a borescope? Is the first mag check ok?

Personally id rather have a field overhaul than send it off to Lycoming.

 

[FPK1]

Does cylinder glazing cause any problems other than high oil consumption?

Yes, failure of the piston rings to set, blow-by, spark plug fouling, and reduced compression and power.

Once glazing has set in, you typically cannot "burn it off" by flying hard. The glaze is harder than the metal of the rings. Unfortunately, the cylinders must be removed from the engine, mechanically honed (roughened up again) to restore the cross-hatch pattern, and re-installed with new piston rings to restart the break-in process...

 

[Daleandee]

Yes, failure of the piston rings to set, blow-by, spark plug fouling, and reduced compression and power.

Usually the excess blowby causes the new oil, after a change, to darken quickly ...

 

[Philip98]

Ah, I was going by the "field overhaul" from the OP, but I do see the last post that mentions a shop now.

I wouldn't be using either the shop or the mechanic again if things are described accurately

Yes, failure of the piston rings to set, blow-by, spark plug fouling, and reduced compression and power.

Once glazing has set in, you typically cannot "burn it off" by flying hard. The glaze is harder than the metal of the rings. Unfortunately, the cylinders must be removed from the engine, mechanically honed (roughened up again) to restore the cross-hatch pattern, and re-installed with new piston rings to restart the break-in process...

We have checked the compressions, which is normal. Power output also seems normal, aircraft goes book speeds and climbs at book rates. Really the only unusual indication is the high rate of oil consumption and one cylinder being colder.

 

[WDD]

Do the oil pooling test. Compression tests didn’t do anything for me to find the source of oil burn. You might have a bad valve guide, etc?

 

[Ed Haywood]

Have the engine shop that did the overhaul check it out. Might be a warranty claim.

 

[flyingcheesehead]

Have the engine shop that did the overhaul check it out. Might be a warranty claim.

I've never seen an engine shop warranty that covers bad break-ins, which this would be.

 

[mondtster]

I've never seen an engine shop warranty that covers bad break-ins, which this would be.

From what I see here, that hasn't been proven. And even if it does turn out to be a break in problem, discussing this with an engine shop will yield far better results than posting on PoA will.

There is no indication of what kind of cylinders are even on this engine. New? Overhauled? There has also been no indication of what kind of bore finish they have. Chrome? Nickel? Steel? Were the right piston rings used for the cylinder finish? Were the ring end gaps checked? How are the valve guide clearances?

There hasn't been mention of whether or not the engine shop ran the engine on a test stand to do the initial run in or if that was left to the installer and owner. I know I wouldn't turn any engine loose that I have overhauled or repaired without running it myself, so the "wrong oil" might not really be a problem at all.

With 150 hours and high oil consumption it is reasonably safe to say something is going on that needs attention, but nobody knows what that problem is at this point. It could be a lot of things.

 

[tms2x2]

You're completely glossing over the field overhaul spec. Lyc spec (aka thier own maths) say that OPs WELL WITHIN oil burn spec. They do say that to use mineral oil but they also say that if you don't, break in could take longer. Is it high? Maybe.

OP is also not being very specific.... a HALF QUART per hour variable is quite a large delta. Was the oil accurately measured when drained? ? How much oil is OP putting in? Is the motor being overfilled (say 12 qts) and then when it normalizes to 8-9qts its considered a problem? What are the current compressions? Improperly broke in rings/cylinders are not hard to find.

Unless there is oil on the bottom plug/in the cylinder there is nothing pointing directly to an oil control problem. OP hasn't give much other than a vague burn number.

The bottom line is that they engine is burning oil within spec. I hope OP also pulled plugs to look for oil and should also 'scope the engine. If the motor is making rated static RPM I don't see a problem worth taking off six jugs and introducing the possibility of even more issues.

No intellegent MX is gonna pop off cylinders and mess with through bolts unless there are clear signs of an actual issue. So far (due to OP's lack of feedback) there is nothing to show that there is a problem.

The fact that so many are wanting to attack a non-issue (from what we know so far) tells me that common sense ain't that common. If OP reports back with more clarifying data then sure, there may be another course... but after 100+ hours of flying and no reports of running rough (oil fouled plugs, not making rated RPM).

If your MX wants to rip into your motor becuase the owner THINKS oil consumption is high (although its not) then you need a new MX.

$8.75 quarter for Phillips. 2 hours per quart consumption. 2000-150 hours to go to TBO. 1850/2*8.75‎ =$ 8,093.75

Oil consumption becomes an issue when it is annoying to the pilot Everywhere you go you need a case of oil in the baggage. 2 hour flight. Add oil. 4 hour flight add more oil. Engine run up, bad mag check, need to burn the oil off the plugs to pass mag check. Then need to burn off the plugs to stop a lumpy idle, burn off the plugs to pass mag check. Check the mags after waiting for clearance, oops, failed, burn the plugs off again. How much of an annoyance it is to the pilot is the determining factor.

The formula from Lycoming is a guide to determine for the mechanic when to recommend repair. It is not to be considered a normal amount of oil burning. 5 hours per quart consumption for an older engine. New factory Lycoming consumption is 20 or more per hour usually.