How Many Hours Between Oil Changes?

[MyNameIsNobody]

Our plane has been flying about 75-100 hours a year.  Oil is changed at annual and then we change at an interval of:

30-35 hours between changes.

I saw another thread that was 50-75 hours so thought i would throw it out.

[Browncbr1]

 

25 hours change oil. I change filter every other oil change (@50)

 

 

Sent from my iPhone using Tapatalk

 

[MBDiagMan]

Change oil hot & change oil often!  

If the plane has a good tight engine with no blow by AND is being flown regularly and often, the oil change interval can stretch a bit.  If the oil will be drained when the engine is hot and be allowed to drain an extended interval, it will provide a more thorough cleaning, helping with the slightly extended interval.  For those doing their own changes, the hot, overnight drain can be manageable.  If you are hiring it done, very few shops will do this or even believe that it is helpful.

My $0.02,

[MB65E]

I change mine every 20hrs. But let the filter extend to the next oil change. Ever see what your oil looks like at 50hrs? Not golden honey anymore. 

-Matt

[Zwaustin]

Oil and filter with analysis every 25 hours for me

[kpaul]

Oil and filter with analysis every 25-30 hours for me

[LANCECASPER]

36 minutes ago, Zwaustin said:

Oil and filter with analysis every 25 hours for me

Same here

[Oscar Avalle]

Oil and Oil filter every 30 - 40 hours

[MooneyMitch]

Ditto for me on the 25 hour intervals for oil/filter.  I also consider the 3 month duration.

If I don't reach 25 hours within 3 months or so, I change oil and filter ( whoops, my new little Mini-Mooney does not have a filter.  If it did I'd change it each oil change)

Happiness to you with you Mooney 

[RLCarter]

Oil is cheap compared to the components it protects, 25~30 hrs has been my norm. It's my opinion that letting the oil drain for more than an hour is a total waste of time, my procedure is plan the oil change after a flight, get the oil draining, remove top cowl, remove the filter and cut open and inspect, If all looks good fill in the info on the filter and fill with oil and reinstall, clean any oil mess up from the filter area, remove the drain hose and fill with oil, test run to check for leaks then re-cowl. The above procedure it's a step by step and doesn't account for looking at everything while the cowl is off, the screen gets pulled at annual, the oil may or may not get changed at annual (if it has less than 20hrs, it stays)

[AH-1 Cobra Pilot]

50 hours, per the book.

[MyNameIsNobody]

1 hour ago, MB65E said:

I change mine every 20hrs. But let the filter extend to the next oil change. Ever see what your oil looks like at 50hrs? Not golden honey anymore. 

-Matt

I have not.  (Seen what 50 hour oil looks like).

Truth be told oil gets changed 2-3 times a year with 25-30 hours being the criteria.  I have no "time" criteria as it is getting flown often enough that it is emptied before it reaches that hour mark.  Over winter in Midwest plane does not get flown much so depending on change not a lot of hours are going on from December through February.  Annual is February so it gets new oil for upcoming "flying season".  Camguard has been added for 700 hours post overhaul.

[RLCarter]

One of the byproducts of combustion is acid, which gets suspended in the oil, I wouldn't store (not fly) oil that is high time. If you know there is a time of inactivity coming up and it's close to an oil change do it before the storage

[DXB]

30-40 hrs or 3-4 months, whichever comes first, along with new filter. For me they usually coincide pretty well.

[MooneyMitch]

As I ponder further on this subject, I think of synthetic oil.  In our autos, with synthetic, we can travel 10K miles or 1 year between oil changes. 

I'll bet there is internet [Mike Busch, etc.] information on this, I just have not looked.

So, oil change frequency with synthetic?  What say you all?

[Browncbr1]

Synthetic oil does not do as good of a job of suspending byproducts. There are additives to help this, but conventional oil is best for keeping dirt in suspension to avoid sludge. I personally use the Exxon elite blend which with avblend. The Exxon elite has additives that function like camguard.. it is a blend, so most of it is conventional to keep particulate in suspension and the avblend supplements that as well. But, even with a fraction of the oil being synthetic, I still change at 25 hours to keep clean and less acidic.

 

 

Sent from my iPhone using Tapatalk

 

 

[LANCECASPER]

1 minute ago, Browncbr1 said:

Synthetic oil does not do as good of a job of suspending byproducts. There are additives to help this, but conventional oil is best for keeping dirt in suspension to avoid sludge. I personally use the Exxon elite blend which with avblend. The Exxon elite has additives that function like camguard.. it is a blend, so most of it is conventional to keep particulate in suspension and the avblend supplements that as well. But, even with a fraction of the oil being synthetic, I still change at 25 hours to keep clean and less acidic.

 

 

Sent from my iPhone using Tapatalk

 

 

That's exactly correct. The synthetic was much more slippery so had some good qualities but thinking they could keep it in there on an extended basis was wrong. The lead and other contaminants did not stay suspended and turned into black sludge if kept in for a long time. If people changed it every 25 hours it was probably the best of both worlds.

[MyNameIsNobody]

1 hour ago, RLCarter said:

One of the byproducts of combustion is acid, which gets suspended in the oil, I wouldn't store (not fly) oil that is high time. If you know there is a time of inactivity coming up and it's close to an oil change do it before the storage

Agree.  One time that oil is changed regardless of hours is in the late fall.

[Godfather]

200 hrs per year - 40-50 hr interval 

100 hrs per year - 30 hr interval

[StevenL757]

25 hours oil and filter, or 3 months, whichever comes first.  Your engine will thank you.  It baffles me how some folks will protect an engine worth tens of thousands of dollars by eliminating a ~$50 oil change (assuming you do it yourself - I'm guessing at the DIY cost) by going to a longer interval, especially when the airplane flies 75 - 100 hours per year as the OP indicated.

"25 hours or 3 months - oil and filter...Just Do It"

:-)

[ArtVandelay]

Whenever it turns black, 25+ hours

[Mooneymite]

My previous engine went 2400 hours and was running well when I replaced it with a F Reman.  The oil and filter had been changed every 50 hours, so that's what I've been doing with the new engine.  I use W 100, or W 100+, no synthetics.

Obviously, changing the oil more often is not going to hurt the engine.  Clean oil is good oil. 

[N201MKTurbo]

I watched a video from Shell Oil once. They were pretty adamant about not letting the oil change go more than 4 months. They seemed more concerned with the calendar time than the engine time.

[75_M20F]

25hrs or 4 months (whichever occurs first) for me, however 50 hrs or 4 months is permissible.

[Steve W]

Great, now I need an oil change too... Of course I knew that when I picked up the plane that I'd need one when I got home.