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Warming Engine Before Oil Change?

R

rdockery_3

Active Member
I know that Rotax recommends warming the engine to operating temperature before draining it, but I couldn't find an actual number listed in the maintenance manual. Is 122 degrees considered operating temperature or do I need to get the temperature up to the 180-190 range?
 
rdockery_3 said:
I know that Rotax recommends warming the engine to operating temperature before draining it, but I couldn't find an actual number listed in the maintenance manual. Is 122 degrees considered operating temperature or do I need to get the temperature up to the 180-190 range?
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Anything over 122 should be fine. The goal is simply to warm the oil so that it is less viscous and will drain more readily/thoroughly.
 
I just watched a 2 hour Youtube video by Lockwood on familiarization with the Rotax family of engines. They do not recommend warming the engine first, as all the oil with its contaminants is in the reservoir with burping after the previous flight, and who wants to work on a hot engine. They do suggest frequent cleaning of the reservoir for lead deposits if burning Avgas and the use of a Decalin like product.
 
flightdoc101 said:
I just watched a 2 hour Youtube video by Lockwood on familiarization with the Rotax family of engines. They do not recommend warming the engine first, as all the oil with its contaminants is in the reservoir with burping after the previous flight, and who wants to work on a hot engine. They do suggest frequent cleaning of the reservoir for lead deposits if burning Avgas and the use of a Decalin like product.
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I would think you'd be leaving more old oil in the engine by not warming it though. My oil level is always lower when I burp the engine cold vs burping right after flying.
 
rdockery_3 said:
My oil level is always lower when I burp the engine cold vs burping right after flying.
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I felt the same way until calculating the volumetric expansion which adds about 120ml for hot oil. That equates to approximately 1/4 of the flat spot on the stick. What is also to consider is the warm oil is easier to burp.
 
seagull said:
I felt the same way until calculating the volumetric expansion which adds about 120ml for hot oil. That equates to approximately 1/4 of the flat spot on the stick. What is also to consider is the warm oil is easier to burp.
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If you anticipate an oil change before the next flight, "burp" the engine after the preceding flight. Then, all the oil is in the reservoir, and you can work on a cold engine.
 
flightdoc101 said:
If you anticipate an oil change before the next flight, "burp" the engine after the preceding flight. Then, all the oil is in the reservoir, and you can work on a cold engine.
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Not sure where to start with this, except to say that If this is how the 912 worked there would be no need for the burping process at all.

When the engine is shut down, it is essentially burped. As the engine sits oil will flow back to the crank case over time. This is the reason that the burping procedure is necessary, returning oil to the reservoir for an accurate level check.
 
rdockery_3 said:
I know that Rotax recommends warming the engine to operating temperature before draining it, but I couldn't find an actual number listed in the maintenance manual. Is 122 degrees considered operating temperature or do I need to get the temperature up to the 180-190 range?
Click to expand...
We used to immediately drain oil when something came in the shop for oil change or annual. If it’s not hot, pop the drain plug a 5pm and the next day you’re good to go. It’s just because cold oil has the consistency of Golden Eagle Syrup and takes forever to drain.
 
flightdoc101 said:
I just watched a 2 hour Youtube video by Lockwood on familiarization with the Rotax family of engines. They do not recommend warming the engine first, as all the oil with its contaminants is in the reservoir with burping after the previous flight, and who wants to work on a hot engine. They do suggest frequent cleaning of the reservoir for lead deposits if burning Avgas and the use of a Decalin like product.
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You should be doing compression checks on a hot/warm engine. So that’s why it makes sense to kick off annuals with oil change and compression checks. But you do need some gloves because those plugs will be hot.
 
D-Dubya said:
More warmer is more better.
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Yep, before every oil change - I alway go fly out to the practice area, play around for 5 min with some acro and then straight back into the hanger to decowl, dipstick out and drain the oil while its still hot. I then get the filter off and drain that too. Once everything in the pan has drained out, I'll even do the extra step of putting the tail wheel up on a sawhorse or stool to get the nose level and drain that last tiny bit out of the pan, since my drain plug is on the FWD edge of the oil pan.
 
I’ve done more oil changes in my 50 years of driving planes than I can count! ALL where done hot! One of my current A/C has a 912 and I never burp it as I check the oil when I’m done flying, that’s the true level when it’s operating.
Each to their own👍
 
On a full moon night, after a session of snap rolls…preferably outside…with Andre Bocelli on the CD, because everyone knows you have to have the proper oil harmonic prior to an oil change to keep the particulates in suspension…then and only then…when the resonance of the universe aligns, can you let the liquid pour from the drain.

It’s preferable to stand on one foot as you drain the oil barefoot, so as to be grounded…for earthfulness… as the oil cools you dip two fingers and make oil whiskers on your cheeks…under strong LED pen light, if your cheeks glow metallic….you are doomed for all eternity.

If you just glisten…continue.

The Oil Blessing is quite complicated and should only be attempted by those most knowledgeable few souls who can divine cam/lifter provenance and speak in the tongues of petroleum distillates and metallurgical mayhem.

Buy an extra quart….pour it….wear it….be one with the universe…Go forth with the oil…and prosper

and thou hath…aviation.
 
Yeah, ummmm...I know that stuff is legal in a lot of states, but you probably shouldn't be using it heavily when you're on the VAF forum. Just sayin'...
 
Capt said:
I’ve done more oil changes in my 50 years of driving planes than I can count! ALL where done hot! One of my current A/C has a 912 and I never burp it as I check the oil when I’m done flying, that’s the true level when it’s operating.
Each to their own👍
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Is it a good idea to start the engine without all of the oil being in the reservoir?
 
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