Are we still debating that you have to get the plane in the air VS running it on the ground for 30 minutes is good enough to get the moisture out?

midcap

midcap

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midcap
I'm back sauce bosses, anyhow....if you can't fly your plane...just run that rascal on tie downs for a 1/2 hour every week...Keeps the moisture out.

Prove me I'm wrong
 
Is someone trying to prevent you from doing what you want with your airplane?
 
I just hope you make sure no planes are behind you when doing these ground runs.
 
No one cares where I am, but I remember here we had some folks saying it's not the same
 
I make sure to do it in front of the planes who are about to get new paint, it's free sand blasting!:p
 
Even if it's not true....

If you have the time to ground run you have the time to fly. Why own a plane you don't fly?
 
Oil temperature is the key. Most articles state that you need the oil to reach at least 180F degrees for at least 30 minutes to remove the excess moisture in the oil. Not sure you can get to that temperature on the ground at a safe power setting. If you do, please make sure the surface under your prop tip is clear of any debris. Minor dust can ding your prop and throw junk into the plane behind you.
 
BillTIZ said:
Oil temperature is the key. Most articles state that you need the oil to reach at least 180F degrees for at least 30 minutes to remove the excess moisture in the oil. Not sure you can get to that temperature on the ground at a safe power setting. If you do, please make sure the surface under your prop tip is clear of any debris. Minor dust can ding your prop and throw junk into the plane behind you.
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totally agree with this.....there is no reliable way to get the oil hot without overheating the cylinders....on the ground.
 
midcap said:
Prove me I'm wrong
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Lots of threads on this already. It has been beaten to death more than once. Some owners will believe what they want to believe, no matter what the engine makers say, or what we mechanics find in ground-run engines say.

You will wreck your engine doing this, which is more business for the manufacturers and the maintenance shops.
 
If you have 30 minutes to an hour to go to the airport and run your plane on the tiedown why not just fly it? If it or you aren't airworthy why not just pickle it?
 
The fact that you are ground running it when it's a seller's market and airplane prices are sky high sort of tells me something about your mental state. :)
 
ground running doesn't give the engine enough work for it to be anything worried about.
I always thought lower temps are good, but that is not the case, there is a sweet spot temperature, especially for the oil which is >180 and < 225, it makes total sense
if you think about it, there are a lot of contaminants that don't burn off easily and then there is the artifact of moisture you don't get rid of that with a ground run, you'd just circle it around with the sh#t that is already there, so you're basically mopping the floor with a dirty broom.
With 100LL case you build up more lead on your plugs for instance, I have seen it on plugs that did ground runs only, it is nasty!

I usually run LOP at <50% power at TAS of 120, I was advised to run at times 75% ROP, it is important for the engine to work harder at times, but as always CHT and oilT are the 2 ones to monitor.

And in addition if you have the engine running make a pattern flight or 3 and remain vfr day currency! double bonus :)
 
So, ground running an aircraft chews up your prop while providing insufficient cooling for the engine. Unless you are running it at idle, in which case you are carboning/leading up the plugs and valves, while not heating the oil to a high enough temperature to evaporate moisture and volatile acids. Keep in mind the way moisture "gets in" is by running the engine. (Water is a byproduct of combustion.) If the airplane is sitting idle, there is really not that much moisture ingress into the engine. What was in there was put there by the last time it was operated. Why is it so hard to just fly it, the way it is designed to be operated?
 
Grum.Man said:
If you have 30 minutes to an hour to go to the airport and run your plane on the tiedown why not just fly it? If it or you aren't airworthy why not just pickle it?
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When the topic comes up it typically involves an airplane that is in storage because it is either out of annual or the owner is without a current medical.
 
Kenmore Air Harbor used (40 years ago) to have a service where they would run customer's airplanes once a week.

They stopped doing it when these airplanes all started to have rusted-out engines.
 
Salty said:
Even if it's not true....

If you have the time to ground run you have the time to fly. Why own a plane you don't fly?
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Lost medical but thinks he'll get it back and wants to make real plane noises in the meantime?

Likes the status symbol of owning a plane?

Really dialing in start procedure and exactly how many shots of primer work best?

Hates his significant other and just needs something to drown out the noise but doesnt pass the IMSASFE checklist because of the above.
 
The real answer is most people are NOT debating this as they know the proper answer.

The OP seems to not be one of those.
 
Pinecone said:
The real answer is most people are NOT debating this as they know the proper answer.

The OP seems to not be one of those.
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Maybe not. Perhaps he's just upping his post count.

:p
 
The #1 rule of owning an airplane: fly it regularly.
Good for the engine, the airframe, the pilot's skills, and his health & happiness.
Also use CamGuard, especially for Lycomings that have the cam above rather than below like most Continentals.
 
Dan Thomas said:
Lots of threads on this already. It has been beaten to death more than once. Some owners will believe what they want to believe, no matter what the engine makers say, or what we mechanics find in ground-run engines say.

You will wreck your engine doing this, which is more business for the manufacturers and the maintenance shops.
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OP didn't specify whether he wanted to wreck his engine or not. He only wanted to prove that ground runs reduce crankcase moisture. He's probably right that they do. :)
 
schmookeeg said:
OP didn't specify whether he wanted to wreck his engine or not. He only wanted to prove that ground runs reduce crankcase moisture. He's probably right that they do. :)
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It doesn't, however. Combustion generates moisture. Shell and Lycoming both tell you that you need to get the oil temperature up to about 180°F for a period to boil off the water.

We used to have a clown who would run up his 172 (he even got out of the thing while it was chugging away) in his tie down blasting stuff on the guys behind him. I tried to explain to him he was doing more harm than good, and if flying it for 30 minutes wasn't something he could do, that I'm sure I could find someone to do it for him for free.
 
schmookeeg said:
He only wanted to prove that ground runs reduce crankcase moisture. He's probably right that they do. :)
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They don't. As a mechanic, I have seen it too often.

I have taken the rocker covers off engine that had just landed. Oily inside. I have taken the covers off engines that landed the afternoon before, were run up in the morning before inspection, and there was lots of water in them. I've even found water droplets between the piston and cylinder walls in those cases.

Ground-running generates crankcase moisture much faster than it can be expelled.
 
midcap said:
I'm back sauce bosses, anyhow....if you can't fly your plane...just run that rascal on tie downs for a 1/2 hour every week...Keeps the moisture out.

Prove me I'm wrong
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It’s not my job to prove you wrong. Do what you want with your plane. I choose not to ground run my plane. Sometimes it is unavoidable, but I work hard to avoid running my aircraft on the ground. Understanding as I do, the chemistry, the metallurgy, and the mechanics of the engine, you would avoid it, like the plague.
But again your plane, your money.
 
Fearless Tower said:
When the topic comes up it typically involves an airplane that is in storage because it is either out of annual or the owner is without a current medical.
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Or it's someplace with a winter and very few days that are both non-working days and flyable. (not endorsing ground runs, but that's the other reason some people think about doing them)
 
I'm still imagining it being less moist after 30 minutes of running a motor than the ambient and constant swamp that is Louisiana. :D
 
Ain't work the effort. Never did that with any of them and there is almost zero corrosion in a 55 year old O320 I just saw ripped apart first time since birth.
 
schmookeeg said:
I'm still imagining it being less moist after 30 minutes of running a motor than the ambient and constant swamp that is Louisiana. :D
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It is not dryer. Again, combustion makes moisture. If the oil isn't hot enough to boil it off, it just accumulates in the sump. I can't tell you the number of times I've run the engine a bit to warm up the oil to change it and the first thing that comes out of the sump is water.
 
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