Oil consumption

I added a little over half a quart to the sump during the first 25 hours and changed oil at that point. After 26 more hours I've added a little over a half-quart more (not all at one time) and the oil is definitely dark, though not black.
This is my first experience with a Rotax and am wondering if this is in the expected range. I've used MOgas only and plan another oil change at the condition inspection (75+ hours??).

Thanks

Wayne 120241

yankee-flyer said:

I added a little over half a quart to the sump during the first 25 hours and changed oil at that point. After 26 more hours I've added a little over a half-quart more (not all at one time) and the oil is definitely dark, though not black.
This is my first experience with a Rotax and am wondering if this is in the expected range. I've used MOgas only and plan another oil change at the condition inspection (75+ hours??).

Thanks

Wayne 120241

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Hi Wayne,

The Rotax normally uses no oil between changes so I am sorry to say that you may need to explore the issue further, could be that you may be adding to much oil and it is getting blown out. I assume that you are carefully following the correct procedure for checking and adding oil, by getting a good burp when you check it and then only adding oil to the top of the flat on the dip stick, also that you are sticking the dip stick all the way into the oil tank when checking the oil. If any of these procedures are not followed you have been adding to much oil and you can find some of it on the belly of your RV-12 I would guess, just behind the oil breather tube.

Good luck with it and I hope it comes out OK for you.

Best regards,
Vern

Wayne,

Per the Rotax Operators manual you can expect higher consumption during the first 25 hours. The manual, on page 2-10, lists max oil consumption as 0.13 pints/hour. In 25 hours that would be 3.25 pints. Since you are using 1/2 quart in 25 hours you are well within that limit.

Having said that, I don't know of anyone using that much oil. With 260 hours on my 912 I have never used a measurable amount between oil changes at 25 hours or 4 months whichever comes first. It uses such a negligable amount that I almost become complacent at preflight.

When checking oil level, are you in a level spot, preferably the same spot, each time? Do you burp the engine per instructions each time you check it? I only suggest being in the same spot since you are trying to get a consistent measurment to determine if you have a problem.

As for how dark it is, mine does get darker but not a lot. If you are concerned you should do oil analysis.

Anyhow, you are within Rotax limits so I don't think you have a problem. My suggestion, barring anything else that comes up, is to inspect the engine closely at the condition inspection and continue to monitor your consumption.

Wayne,

I also assume that you have been checking the mag plug and opening the oil filter at each change and that you are finding them clean. You can expect a little fuzz on the mag plug at first change then it should be relatively clean each time. The Rotax manuals give a visual example.

Oil check

Mag plug and filter were both good at 25 hours. The engine is burped at each check with the airplane at the same spot in the hangar. With the engine cold the oil level is just ay the bottom of the flat spot. Burping after flight (with a HOT dipstick) has the oil mid-way on the dip-stick. Should I have more oil in the system? I started each time with the recommended 3.5 liters.

Thanks

Wayne

Oil Consumption

Is that 3.5 LITRES or 3.5 QUARTS???
Meade
N612RV

Oil Burn!

Again I think this is about flying technique. IMHO you are doing fine and keep on flying. If I fly here in Texas in 100F heat and run my engine hard, like around 5400RPM with oil temps up around 225 to 230F. Ill burn more oil than you flying around in 85F heat with oil temps around 190F at 5000RPM. Also I think when oil temps are hotter than yes some oil will go out the vent tube. I have some oil on my belly. If you take a rag and wipe the belly and it comes up oily then thats where some of your our oil went. Check it out and see. If you haven't painted your RV12 yet it will be harder the see visually. Also flying longer flight in high heat may effect it. Like I fly two hour flights and you only fly one during your daily flying session. I know of 3 RV12s here in Texas that burn some oil.

What I am seeing - -

I have an oil therm, and it still takes about 3.5 liters for a change. ( I drain the cooler each time also ). After burp hot, have it about mid-way on the flat part of the stick. In 100 hours, I will use the other 1/2 liter of oil, so it works out well. 4 liters to 100 hours ( then changing ). Mogas only.

266.1 hours after morning breakfast ( MXO ) flight.

John Bender

Normally I use 3 quarts at oil change. that puts it about mid point on the flat spot. At my last change I filled it to the top of the flat spot thinking more oil would help keep oil temps down during summer. I was worried that I might have a mess on the belly being so full but that hasn't happened. Today, at 20 hours since oil change, the oil level is still at the top of the flat mark. I can't say it did anything for oil temps but it hasn't been throwing any overboard. I do, however, have it on good authority that over filling will result in oil going out through the breather.

Wayne - if I were going on a long flight and the cold oil check was at the bottom of the flat spot, I would add 1/2 quart. Just my personal preference.

sandpiper said:

if I were going on a long flight and the cold oil check was at the bottom of the flat spot, I would add 1/2 quart. Just my personal preference.

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It is only about a cup from the bottom of the flat to the top of the flat. When the oil is hot it always measures higher on the flat. If you add a 1/2 quart to your cold engine you are going to have a oily belly after it warms up.

JBPILOT said:

I have an oil therm, and it still takes about 3.5 liters for a change. ( I drain the cooler each time also ). After burp hot, have it about mid-way on the flat part of the stick. In 100 hours, I will use the other 1/2 liter of oil, so it works out well. 4 liters to 100 hours ( then changing ). Mogas only.

266.1 hours after morning breakfast ( MXO ) flight.

John Bender

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Same here except I use mogas with subsidized ethanol because it is the only thing available. Rotax says its okay but my lawnmower hates it...go figure? 244 hours

Pete

RDOG - You are correct. What I meant was I would put enough in to get half way up the flat spot. A lot of dip sticks are a quart between marks but not this one. Just a little brain f**t from an old dip stick!!