DA62 oil consumption

[Boatguy]

My DA62 engines seem to go through more oil than my DA40NG engine did. Nothing like a Lycosaurous, but still more. I'm curious to learn what DA62 owners experience in the way of oil consumption. I'm not quite certain if I have a measurement problem, the oil is being "burned" or just blown out the breather.

Any data on consumption, perhaps accompanied by usual cruise power settings, would be appreciated.

[michael.g.miller]

I'd compare Applies to Apples before jumping to any big conclusions. At 75% power, your DA62 will operate at 180 * .75 = 135hp. At 75% power, your old DA40NG will operate at 168 * .75 = 126hp. While 9hp might not sound like much, keep in mind that the original Thielert engines were certified at 135hp maximum output (at 100%). Put another way... your 75% power in a DA62, is the same as running a DA40NG at 80% power.

Might be useful to also replay the history for how Thielert and Austro engines were developed... the original Thielert engines were designed to produce 135hp. This has been increased to 168hp first with the DA42 Austros, and now 180hp with the DA62 version. That's a lot of extra power to ask out of an engine not designed to run anywhere near 100% duty cycle, for an auto application. Especially given that none of the core engine has been reworked... it's just a turbo boost, and cooling system change.

Personally, when not in a rush, I like to operate my DA42NG at 60% power, which is 168 * .6 ~= 100hp. This is in line with the original 135hp engine, and will hopefully save my engine blocks for a long-running life. As a part 91, on condition operator, I believe this will lead to the best long-term financial outcome.

[Chris]

I was just browsing these old threads about oil consumption the other day. It seems like 1-2 quarts every 100 hours is normal for both the DA42 and DA62, with some outliers reported.

[Boatguy]

I'd compare Applies to Apples before jumping to any big conclusions. At 75% power, your DA62 will operate at 180 * .75 = 135hp. At 75% power, your old DA40NG will operate at 168 * .75 = 126hp. Put another way... your 75% power in a DA62, is the same as running a DA40NG at 80% power.

Interesting math, but a bad assumption. I ran my 40NG at 85% so...

.85 * 168 = 143hp
.75 * 180 = 135hp

Using your math, and assuming, though I don't know of any basis for this, that oil consumption varies with engine load, the DA62 should be consuming less oil.

[Boatguy]

I was just browsing these old threads about oil consumption the other day. It seems like 1-2 quarts every 100 hours is normal for both the DA42 and DA62, with some outliers reported.

Well lazy me. I should "search before I post". Thanks for pointing that out. 1-2 liters is what I expected. I add in .5 liter increments so I guess adding every 25-50hrs should be expected.

I have a measurement issue also as the nose wheel tilts the nose up and shifts the oil aft which lowers the level on the stick. The last oil change was at the factory where they added 6 3/4 liters to each side (why not 7?), and the dip stick read about half way between min/max when I would have expected it to read Max. The AFM says the min/max quantity is 5/7 liters. Does that mean that Min on the stick is 5 liters and Max is 7 liters, 2 liter band, because it never seemed like that with the 40NG.

[thommy152]

Russ,

I too have noticed the same issue with the oil level on the dipstick varying with the changes in the length of the nose gear strut. My DA62 nose strut appears to naturally rest at a longer length than other DA62’s I’ve seen. This causes the oil to read lower on the dipstick which may lead to me adding oil when not needed and could also explain why the oil burn in my engines are higher than some others have experienced (maybe overfilling and the extra being blown overboard?). In 70 hours, I’ve added 3L to the right engine and 2.5L to the left engine. Well within AFM specs, but still much more than the 1L per hundred hours that other Diamond pilots have reported.

A few extra notes: In my limited experience, one liter moved the oil level from the min line to the max line on the dipstick. Lately, I’ve started braking firmly when pulling up to the hangar to compress the nose strut a little bit. I’m going to see if this leads to higher oil level readings, less oil being added, and less oil burn.

[michael.g.miller]

I'd compare Applies to Apples before jumping to any big conclusions. At 75% power, your DA62 will operate at 180 * .75 = 135hp. At 75% power, your old DA40NG will operate at 168 * .75 = 126hp. Put another way... your 75% power in a DA62, is the same as running a DA40NG at 80% power.

Interesting math, but a bad assumption. I ran my 40NG at 85% so...

.85 * 168 = 143hp
.75 * 180 = 135hp

Using your math, and assuming, though I don't know of any basis for this, that oil consumption varies with engine load, the DA62 should be consuming less oil.

Good point, sorry for assuming! Out of curiosity, what oil burn did you see on your DA40NG at 85% power?

[Mjwatlanta]

2019 da40 NG with only 140 tach time. I changed the oil when I bought it last October with about 40 hours tach time. I was concerned about calendar age not hours. I changed it again at annual in April with 80 hours. No oil added between 40 and 80. Now 60 hours later and unless something changes I doubt it will need oil before the 100 hour oil change. I added a little because
I thought the low oil pressure light at idle was because of low oil - it’s not. It has remained at about 4/5 to the max line. Does not appear to be moving at all. Cruise at 88% but have been doing a lot of IFR training at 72% or so.

[Boatguy]

I'd compare Applies to Apples before jumping to any big conclusions. At 75% power, your DA62 will operate at 180 * .75 = 135hp. At 75% power, your old DA40NG will operate at 168 * .75 = 126hp. Put another way... your 75% power in a DA62, is the same as running a DA40NG at 80% power.

Interesting math, but a bad assumption. I ran my 40NG at 85% so...

.85 * 168 = 143hp
.75 * 180 = 135hp

Using your math, and assuming, though I don't know of any basis for this, that oil consumption varies with engine load, the DA62 should be consuming less oil.

Good point, sorry for assuming! Out of curiosity, what oil burn did you see on your DA40NG at 85% power?

The expected 1-2 liters between 100hr changes.

[MackAttack]

I just had my first oil change at 99.5 hours. Went through about 2 liters total in that time (including a liter that Premier added right before delivery; I added about another liter). It was a bit low before I took it up for the oil change but I think my consumption is about 1.0-1.2 liters/50 hours if I stick to the dipstick indications. I normally run at 78% power in cruise; occasionally a tiny bit more and occasionally a bit less, depending on the mission and other factors.