Burning Excessive Oil

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rwtucker
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Re: Burning Excessive Oil

Post by rwtucker »

Roxi5m9 wrote:Hi everyone, new DA40 owner (2004 DA40). Been catching up on all of these threads. Huge amount of info. Thanks to everyone.

I’m having this same issue and am in the process of determining what level of oil my Diamond likes to keep without blowing it over (it’s definitely less than 6). I know the POH says the minimum is 4 qts, and then states 6 for IFR. I personally haven’t seen two different requirements like that before. Does anyone know why they have a higher limit for IFR? An Austrian cert standard maybe?
Some of the thinking about oil reserves may trace all the way back to radial engines. There is no way I could be in the air long enough to burn 2 qts. On the other hand, a cracked ring could change that situation pretty quickly.

Your experimentation will tell you where to keep your oil to minimize blowing it on the belly. For most of us, it is 5 qts or less. I think that the increased IFR requirement follows the same line of reasoning at play in determining reserve fuel requirements. In my experience, a 2-qt margin is excessive in our engines. In my typical longer flights of five hours broken up by one landing and t/o to stretch and top off fuel, I probably burn 1/4th qt. of oil. I'm not certain anymore because I I have not been tracking it closely. On the other hand, since I fly under 5 qts., I maintain my preferred level +/- 1/4th qt. I do not wait until I burn a full qt.
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Rick
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Re: Burning Excessive Oil

Post by Rick »

Roxi5m9 wrote:Hi everyone, new DA40 owner (2004 DA40). Been catching up on all of these threads. Huge amount of info. Thanks to everyone.

I’m having this same issue and am in the process of determining what level of oil my Diamond likes to keep without blowing it over (it’s definitely less than 6). I know the POH says the minimum is 4 qts, and then states 6 for IFR. I personally haven’t seen two different requirements like that before. Does anyone know why they have a higher limit for IFR? An Austrian cert standard maybe?
Also, remember that if you haven't replaced your dip stick with the new model, when you are reading about 5-1/2 quarts on the old stick, you really have 6 quarts in there (according to the new dipstick). This is exactly where mine sits now - right on the (new) 6 line, whereas it used to stay at 5-1/2 on the old stick.

And welcome to the forum, Nick!
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Re: Burning Excessive Oil

Post by Roxi5m9 »

I just read in another forum about the updated dipstick. I’m certain I still have the old one and will be replacing that.

Thanks, and thank you!
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Re: Burning Excessive Oil

Post by Gearle »

I had this excessive oil burning problem AND plug fouling to the point i couldn't taxi to the other end of a runway with fouling my new THIN wire spark plugs AND leaning all the way down the taxiway (see i'm getting all the recommendations out the way) using the thinner PHILLIPS 66 X/C AVIATION OIL 20W-50 ENGINE OIL.
Interestingly when i bought the plane he was using AEROSHELL OIL W100.
That's what i now use again.
No more plug fouling.
NO more excessive oil burning. i would say it's less than 1/2 quart per hour.
i also add CAMGUARD (no comments please lol).
i keep 6 qts in the engine. low oil volume is a MUCH worse problem.
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Chris B
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Re: Burning Excessive Oil

Post by Chris B »

Gearle wrote:NO more excessive oil burning. i would say it's less than 1/2 quart per hour.
Hi George -

Thicker oil will reduce the impact of worn rings and/or valve guides. The trade-off is cold weather starting, which probably does not matter in Houston.

But IMO 1/2 qt per hr is very high oil consumption for our engines. This would be past my limit. Have you inspected the cylinders with a borescope? Does the inside of the exhaust pipe have any oil residue? Did all cylinders foul with the 20-50W oil?

Chris
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Re: Burning Excessive Oil

Post by Gearle »

Chris B wrote:
Gearle wrote:NO more excessive oil burning. i would say it's less than 1/2 quart per hour.
Hi George -

Thicker oil will reduce the impact of worn rings and/or valve guides. The trade-off is cold weather starting, which probably does not matter in Houston.

But IMO 1/2 qt per hr is very high oil consumption for our engines. This would be past my limit. Have you inspected the cylinders with a borescope? Does the inside of the exhaust pipe have any oil residue? Did all cylinders foul with the 20-50W oil?

Chris
Hi Chris, I’m actually guessing badly. I’ll have to think harder about how long it takes for me to put a whole quart in. I’m pretty pendatic about oil since my training years ago and keep it at 6 qts all the time. So I’m usually adding a half a quart most of the time.
2 years ago, about 30-40 hours ago, I did an oil analysis and it was perfect. The compressions were good last year.
Now I realize I might be affected by this bulletin. My mechanics didn’t notice this either!
I had not thought that I could be blowing it out instead of consuming it. I will have to look underneath the plane with more earnest.
No boroscope inspection yet.
Exhaust is sooty black only last time I checked.
I typically had one spark plug fouling, the bottom left rear most on my 2003 io360.
/George
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Re: Burning Excessive Oil

Post by Rick »

Note where your oil level is before your next flight (your "down half a quart" mark), but don't add any. Then fly another hour and check it after it cools. I bet your are still at the same level. Several flight hours later, probably still at the same level. That would be your engine's Happy Place, and it's probably going to blow out anything you add above that point. Both of my DA40's behaved this way, although one was right at 6, the other half a quart below. Add anything over that, though, and I would just be cleaning it off the belly.

You also may find that if you update the dip stick per the SB, your Happy Place is really right at 6 on the new stick! :)
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Re: Burning Excessive Oil

Post by Gearle »

Rick wrote:Note where your oil level is before your next flight (your "down half a quart" mark), but don't add any. Then fly another hour and check it after it cools. I bet your are still at the same level. Several flight hours later, probably still at the same level. That would be your engine's Happy Place, and it's probably going to blow out anything you add above that point. Both of my DA40's behaved this way, although one was right at 6, the other half a quart below. Add anything over that, though, and I would just be cleaning it off the belly.

You also may find that if you update the dip stick per the SB, your Happy Place is really right at 6 on the new stick! :)
Thanks! I hope you're right that all this time I thought it was burning oil but it was blowing it out.
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Re: Burning Excessive Oil

Post by DA40KPAO »

Gearle wrote: i also add CAMGUARD (no comments please lol).
i keep 6 qts in the engine. low oil volume is a MUCH worse problem.
I have been getting mixed messages about Camguard. Can you share if your oil burn has improved since you added Camguard?
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Re: Burning Excessive Oil

Post by Gearle »

I have no comments on Camguard preventing excessive oil burn. i'm using only to protect the engine's metals due to corrosion since I live in a humid environment and don't fly as much as I should (once a week).
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