Engine Break-In Procedure

Ventucky Red

Ventucky Red

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Yeah, yeah, I know follow the manufactures recommendations, but still want to find out what/how you did it.

I know each engine is different, but there are commonalities to the process - right?

Appreciate the info
 
Ventucky Red said:
Yeah, yeah, I know follow the manufactures recommendations, but still want to find out what/how you did it.

I know each engine is different, but there are commonalities to the process - right?

Appreciate the info
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Be night nice to know what make and model of engine.
 
75% power continuously until oil consumption stabilizes.

But yes, it does vary some on engine type.
 
Generally, you want a smooth air day, or time of day since you'll be keeping the power up, a longer flight - right up to 45 min to an hour worth of fuel left, and minimize landings and low power ops, so typically, I want to do the first run directly over the home airport at 500-1000' above the pattern, with long, lazy loops in gliding distance of the field. Once that's done once or twice, I try to do loops between two airports that are reasonably close by. Pay a LOT of attention to emergency options and other precautionary measures.
 
Ventucky Red said:
Yeah, yeah, I know follow the manufactures recommendations, but still want to find out what/how you did it.

I know each engine is different, but there are commonalities to the process - right?

Appreciate the info
Click to expand...

I ran my new lycoming IO-360 on Aeroshell 80 mineral oil for the first 63 hours. For the first 20 hours I kept it at 65-75% power while varying RPM between 2200 and 2500 every 15-20 minutes. I got the airplane new with 5 hours on it from the factory and to be honest I think the break in was already done when I got it. It didn’t use much oil at all(~1 qt per 15 hours) and CHT’s were already normal; they didn’t drop much at all over the next 15 hours. After 63 hours I went ahead and switched to ashless dispersant Aeroshell.

One thing I would’ve done differently is start using ashless dispersant oil with camguard oil additive right away when break in was over and leaned more aggressively at that point too. I probably spent 40 hours longer than necessary on mineral oil and 10 hours longer than necessary at full rich high power. Some say there is nothing wrong with using ashless dispersant from the get go and they are probably right. In my case I had to do a 20 hour flight to ferry the airplane home and incorrectly chose to keep the non-dispersant mineral oil in there. It probably was inconsequential though.
 
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I broke in a zero hour 0-320 H2AD motor 5 years ago. It has been running great with 800+ hrs on it now.
I followed Lycoming break in directions exactly.
First start up was with the cowl off for 10 minutes.
Then put the cowl on and ran it for 30 minutes at 1500 rpms on the ground.
Then 2 hours of flight over farm fields at 75% power and the last 30 minutes at wide open throttle/full throttle at 3000'. 2.5 hours total flight time. Used one quart of oil.
Then the second flight was 65-75% power for 2 hours and then the last 30 minutes full throttle.
It used less than half a quart of oil.
Third flight was 2 hours of normal flight and it used no/very little oil.
In 7-8 hours it was broke in.
Still runs the same today.
Oil usage is 10-13 hrs per quart.
When the oil is fresh it'll last for 13 hours, when it get's dirty it will last 10 hrs.
Lycoming recommended Aeroshell 15-50 for break in and for reg use for this type engine.
I have a oil analysis from every oil change since new. First oil change was at 18 hours and now I change it between 49-59 hours.
bd809d34-35f0-43a7-91e6-b3195aa089a2.jpg
 
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I pressurized and flushed my oil cooler of air and minerial spririts from flushing before start up. I did not turn the engine over first to get oil pressure. I had oil pressure as soon as I turned the key and it started first time within one engine revolution. There's fresh oil in the trick tank. I reconnected the oil line after the flush and pushed fresh oil into the engine through the cooler.

659ae9f7-d20f-4459-a1d7-0824c54f5a8b.jpg
 
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For the IO 540 I just built, we followed Lycoming SB1427C to the letter.

-Pre-lubed the engine by cranking it with the plugs out until we had oil pressure

-1000RPM up to oil temp of 140
-1500RPM for 15min
-brief run up to full power
-Changed oil & filter. No metal, re-used oil (Phillips 25W-40 Type M)

-first flight was 2 hours, first hour at 75%, second hour varying between 65-75%.
-changed oil & filter. no metal, engine burned about 1.5qt. Filled with Type M again

-flew 25 hours, mostly all cross country, keeping power between 65 & 75% power.
-engine burned 2 quarts in this time. Changed oil to 25W40 Phillips XC. I'm considering break-in pretty much done at this point, although I'm not using my usual Camguard yet, and I'm going to change again at 25 hours instead of my usual 50. It seems to me that the actual break-in was completed in the initial 2 hour flight. Many engine shops will do that 2 hours on their dyno/test stand before they deliver the engine.

This is the first engine I've broken in. My shop gets most of their engines from Poplar Grove, which does run them, and they are similarly pretty well broken in when they show up. They skip the "burn in" run and 2 hour flight, and go straight to the 25 hour XC stage. Pretty much all their work is on 8.5:1 compression lycomings. I'd be curious to know if the lower compression engines take longer to break in due to lower cylinder pressures.
 
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Gary Ward said:
I pressurized and flushed my oil cooler of air and minerial spririts from flushing before start up. I did not turn the engine over first to get oil pressure. I had oil pressure as soon as I turned the key and it started first time within one engine revolution. Fresh oil in the trick tank.

659ae9f7-d20f-4459-a1d7-0824c54f5a8b.jpg
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Nice setup. How much pressure was introduced to the tank before startup?
 
3393RP said:
Nice setup. How much pressure was introduced to the tank before startup?
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Thanks
Just enough to get the oil to flow through the cooler. I am guessing 2-5 PSI? Maybe a little more? My PSI gauge broke years ago on the tank.
That was a very crude one time setup with no shut off valves. So I regulated it with how much air I shot into the tank. And can stop it by loosening the filler cap on the tank. I used a CO2 tank for air only because it was convenient. It does not take much air.
 
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I don't remember the details, but the gist was first hour spent circling over the airport at WOT, then a few short local hops with varying power settings, then a nice long XC trip to get to 25 hours. Verify oil consumption stable, change oil from mineral to normal, and resume normal ops.

I did have a drop in oil pressure at about 7 hours which scared the crap out of me. Later concluded the oil pressure setting needed to be adjusted.
 
Minimize ground ops and low power operation during break-in. Run engine at 75% in cruise. Do this until oil consumption stabilizes, which can happen as soon as 5 hours or so. I did this with every new cylinder and with my major overhaul. Zero cylinder issues. I ran a single weight straight mineral oil during break-in as per the repair/overhaul shop recommendations, but this is probably not strictly necessary. (But it makes the shop happy for any warranty service.) After break-in, I changed oil and replaced it with my usual multi-weight oil. For me a Lycoming O-320-E2G, the latest version with high-compression cylinders.
 
Ventucky Red said:
I know each engine is different, but there are commonalities to the process - right?
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Yes. But an important reason to follow the correct procedure is for any subsequent warranty claims if needed. Following any other procedure regardless if similar to other break-in procedures will usually result in a denial of claim. Unfortunately have seen it happen one too many times.
 
O-360-A4A. Initial run was on a dyno at Ly-Con, so no need to worry about initial oil priming. The first thing I did was calculate the 75% and 65% rpm settings for various altitudes, adjusted for anticipated density altitude. I did absolutely everything I could on ground power I could, then did a fairly brisk taxi and a run-up sufficient to ensure everything felt normal and was in the green arc. Full-power climb-out with an eye on the CHTs and then flew 75% for an hour. Landed after that for a fuel sender issue (incorrectly set up, with an always-full tank indication and a wildly wrong fuel-flow value) and then flew 5 hours the next day, never less than 65% power and usually between 75% and WOT. Then, for several reasons, I launched on a 23-hour coast-to-coast trip from CA to VA. Had some concerns about being able to maintain at least 65% power in the mountainous regions, but was able to do so for the most part. All of this was flown using straight-weight mineral oil.

Upon arrival in VA, did an oil change with mineral oil as I planned to do mineral oil until 50 SMOH. Subsequently switched to my preferred Phillips XC 20W250 with Camguard at the most recent change. The engine has run flawlessly since then, burning an almost imperceptible amount of oil and with a very minimal rate of oil darkening. Literally the only issue I have is that the oil temp seems to be running excessively cool. I'm still chasing that one down.

I'm very happy that the break-in was good. At the next oil change, I'm going to borescope the cylinders and switch to my preferred Tempest plugs (as the shop put in Champions).
 
RyanB said:
75% power continuously until oil consumption stabilizes.
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chemgeek said:
Minimize ground ops and low power operation during break-in. Run engine at 75% in cruise. Do this until oil consumption stabilizes, which can happen as soon as 5 hours or so. ...
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^^^ this ^^^
Two more points:
1. Don't let it get too hot despite the high power levels. That means level flight to maximize airflow, and shallow climbs at high airspeeds.
2. Keep it at low altitude; above 5000' the air gets thin enough, it's harder to maintain 75% power.

All of this is what I did breaking in my O-360-A4M. With this engine, oil consumption stabilized after the first 2 hour flight, but I continued following the breakin procedure for another 20 hours. UOA had elevated metals for the first 300+ hours before they stabilized. Total 750 hours now, it runs strong, spins like a top and burns about 1 qt. of oil every 15 hours.
 
MRC01 said:
Keep it at low altitude; above 5000' the air gets thin enough, it's harder to maintain 75% power..
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That is something too many pilots do not know. 75% at 1000' ASL is not the same as at 5000'. The POH/AFM, you know, that little book that has the answers and which a lot of pilots never read, has the charts. You'll need full throttle and redline RPM in level flight at some point just to get 75%.
 
Dan Thomas said:
That is something too many pilots do not know. 75% at 1000' ASL is not the same as at 5000'. The POH/AFM, you know, that little book that has the answers and which a lot of pilots never read, has the charts. You'll need full throttle and redline RPM in level flight at some point just to get 75%.
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RyanB said:
Could you educate me on that? Not arguing, legitimately curious.
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The higher the DA, the more throttle & RPM you need to get the same % power. For example with my 172 at standard conditions, gross weight and level cruise flight, 75% power is:
at 2000', 2550 RPM
at 4000', 2600 RPM
at 6000', 2650 RPM
at 8000', 2700 RPM
 
MRC01 said:
The higher the DA, the more throttle & RPM you need to get the same % power. For example with my 172 at standard conditions, gross weight and level cruise flight, 75% power is:
at 2000', 2550 RPM
at 4000', 2600 RPM
at 6000', 2650 RPM
at 8000', 2700 RPM
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I understand that completely. My question was why is 75% at 1000ft different than 75% at 5000ft? Yes the RPM/Manifold setting is different, but the power output should be the same, ie., 75%=75%.
 
RyanB said:
I understand that completely. My question was why is 75% at 1000ft different than 75% at 5000ft? Yes the RPM/Manifold setting is different, but the power output should be the same, ie., 75%=75%.
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Indeed, that's why I interpreted his statement "75% at 1000' ASL is not the same as at 5000'" to mean what is not the same is the engine configuration needed to produce that power, not the power level which by definition is the same.
 
MRC01 said:
Indeed, that's why I interpreted his statement "75% at 1000' ASL is not the same as at 5000'" to mean what is not the same is the engine configuration needed to produce that power, not the power level which by definition is the same.
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Okay yes, that must be what he was implying.
 
RyanB said:
Okay yes, that must be what he was implying.
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That's it. Without consulting and understanding cruise charts, one can think that 2500 RPM (for example) is 75% wherever you are.
 
I just got through breaking-in an XP470 (P-Ponk). For the first 25 hours, I ran it on straight mineral oil. I flew it like I stole it...full rich, and 70-75% power. For the first 10 hours, I only flew near our local airports in the event of an "infant mortality" event. I changed the oil at 10 hours, and again at 25 hours. Oil consumption and CHTs stabilized rather quickly during the process. At the 25 hour oil change, I switched from mineral oil to ashless dispersant. I had a local A&P borescope the cylinders at the 25 hour oil change, and he said they looked great.
 
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