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New oil checking procedure on the way!

Jetguy

Well Known Member
I just remembered an announcement at the, "Whats New At Vans", forum at OSH. Ryan at Vans stated that they are working on a new procedure to check the oil before flying. The gist of it is you will use you starter for a few seconds with your ignition off to burp your engine. After using the starter any oil shown on the flat part of the dip stick will be considered acceptable for flight. IMOH this has come about to make checking the oil easier cause on a cold engine you may have to turn the prop through up to 20 times to burp the engine.:( Many owners do this procedure after flying because it only takes 5 blade when the oil is hot and thin. But in a flying school environment this would not be practical. Look for a possible POH update in the future describing this procedure in detail. ;)

Any updates Scott?:)
 
I just remembered an announcement at the, "Whats New At Vans", forum at OSH. Ryan at Vans stated that they are working on a new procedure to check the oil before flying. The gist of it is you will use you starter for a few seconds with your ignition off to burp your engine. After using the starter any oil shown on the flat part of the dip stick will be considered acceptable for flight. IMOH this has come about to make checking the oil easier cause on a cold engine you may have to turn the prop through up to 20 times to burp the engine.:( Many owners do this procedure after flying because it only takes 5 blade when the oil is hot and thin. But in a flying school environment this would not be practical. Look for a possible POH update in the future describing this procedure in detail. ;)

Any updates Scott?:)

There is indeed a significant difference on the level of oil shown on the dip stick between hot and cold engine after burping. In my early hours of flight I overfilled the oil tank by just filling to the top of the stick's flat on a cold engine. The result was a nice coating of oil on the belly of my plane that I just discovered during my first annual. This is one more good reason to check the oil on the hot engine. This is the best way for a single user plane but for multi users and flight schools I think that VANs method is good: just don't add oil if the flat part of the stick shows oil on it after burping.
 
use you starter for a few seconds with your ignition off to burp your engine
Some pilots might not want to climb into and out of the plane to check the oil. And some might stand on the ground while turning the start key. Doing that could lead to an accident. Turning the prop by hand could also be dangerous. But turning the prop by hand turns the engine slower than what the starter motor does.
 
Using the starter to check the engine oil level isn't a good practice and Rotax advises against it UNLESS you rotate the prop first to make sure no oil has migrated to a cylinder and causes a hydrolock situation. I just had an ELSA RV12 in LA. two weeks ago that the owner went to hand rotate the prop and it stopped dead in its tracks (#4 cyl). If he had turned the key and used the starter it would have damaged his engine. I would either stick with checking by hand or if you use the starter always rotate the prop a few times to make sure there is no oil in a cylinder. Since you are going to rotate the prop by hand anyway why not rotate it a few more times and be done with it and not climb in and out of the cockpit.
 
Checking Oil Daily

Rotax is actively involved in evaluating and approving the new process.

We've all been taught since the beginning to check the oil before each flight or at least the first flight of the day. Older engines consumed oil and lots of it and it was necessary.

But does the Rotax use oil and if so how much? Does anyone know of a Rotax 912 ULS that experienced an engine problem due to low oil? If so what caused the low oil? I am still checking my oil each day but I'm wondering.
 
But does the Rotax use oil and if so how much?

From my experience with a limited # of engines (5 or so), if the oil level is going down it is usually because of leaks, not because the engine burns oil.

If you have a clean engine compartment, you likely will not be adding much if any oil between oil changes.
 
I guess I am missing the point here. The procedure that I use came from this forum, and it works fantastic for me. When I am ready to go fly, I just remove the oil cap, and lift the dip stick, enough to take a peek at the oil level. Truth be told, I have never had to add any. It is always on the flat. I close up things, do the rest of the preflight, and roll it out of the hangar. Before the start, I do pull through 4 blades; old habit, which is 1 blade for each cylinder. Then, it's time t go fly. After the last flight of the day, I roll it back into the hangar, and open the oil door fully. My pea brain says that this will aid in engine compartment cooling. I then remove the oil cap, and pull 4 or 5 blades though, very slowly, listening for the burp, which usually starts at about the 3rd pull. Now I just put the cap back on. That dip stick is too hot to fool with, so I wait and do that check prior to the next flight. Besides, the oil splash that is up on the dip stick will drain down to the level in the tank, so I never need to wipe and re dip to check it. It just takes a partial dip stick lift, and peek. So, what could be simpler. I've not tried it, but I would bet that you could leave the oil cap on, and still get that post flight burp. Burping hot, is so much easier than a cold engine burp.

Tom
 
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A Rotax engine shouldn't use any oil between changes. It is a very tight tolerance engine and not like a loose tolerance air cooled engine like a Cont. or Lycoming. If you are using oil it is usually because of three reasons. You have a leak that needs addressing (you usually see this all over your engine or some part), an old engine with high time that has used a lot of 100LL or the oil level check which gets you in the ballpark has lied to you and you misread it. This last one happens a lot and many add oil before running the engine and double checking the level which can cause oil to flow out the oil tank breather tube and or if its too full can and has caused a hydrolock situation. This is exactly what happened to the owner I talked to a couple weeks ago. The old oil filters and the mounting of an oil tank too high in relation to the engine was another cause. Hydrolock is certainly less prevalent now days over yesteryear.

The procedure of using the starter to check the oil level by rotating the prop will work fine, but I wouldn't do it before I rotated the prop a few turns to make sure oil didn't migrate to a cylinder. Once you turn the key it's too late if there is oil in a cylinder.

I would be absolutely stunned if someone from Rotax doesn't mention this since we always talk about it in the Service level class.

The overwhelming majority will never have hydrolock, but eventually someone will and it is usually from something they did. It has happened before and will happen again.
 
I guess I am missing the point here. The procedure that I use came from this forum, and it works fantastic for me. When I am ready to go fly, I just remove the oil cap, and lift the dip stick, enough to take a peek at the oil level. Truth be told, I have never had to add any. It is always on the flat. I close up things, do the rest of the preflight, and roll it out of the hangar. Before the start, I do pull through 4 blades; old habit, which is 1 blade for each cylinder. Then, it's time t go fly. After the last flight of the day, I roll it back into the hangar, and open the oil door fully. My pea brain says that this will aid in engine compartment cooling. I then remove the oil cap, and pull 4 or 5 blades though, very slowly, listening for the burp, which usually starts at about the 3rd pull. Now I just put the cap back on. That dip stick is too hot to fool with, so I wait and do that check prior to the next flight. Besides, the oil splash that is up on the dip stick will drain down to the level in the tank, so I never need to wipe and re dip to check it. It just takes a partial dip stick lift, and peek. So, what could be simpler. I've not tried it, but I would bet that you could leave the oil cap on, and still get that post flight burp. Burping hot, is so much easier than a cold engine burp.

Tom

Ditto. Works great for me. (Minus the 4 blades on preflight)

What is "hydrolock"?
 
I used to get a hydro lock sometimes on the Yak-52 I used to own. Oil would pour out of the exhaust when it finally cleared. I miss the mystique of that radial!😁
 
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