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Avoid rust in the engine; how?

A good fellow on this website crafts a nice dryer which attaches to the oil filler port on the engine.

Basically, he makes a tube which is filled with a dessicant that is blue when dry and effective, pink when it needs to be recharged. An aquarium pump is utilized to pump air through a filter and into the bottom of the dessicant tube. The air exits at the top of the tube, through another filter. The tubing is connected to an attachment which then is affixed to a plug that is threaded to fit the oil filler port. He sets the timer to activate for a few minutes at a variety of times throughout the day.

Our engine gurus at Bolduc Aviation/Horizon thinks this to be quite helpful.

There is a different plug for each aircraft.

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Note the small clear plastic observation port just below the exit point of the dessicant tube, which allows me to see when it is time to dry the dessicant. When it turns pink I simply take off the top of the dessicant tube, pour the dessicant beads into a bucket, take them home and put them in a turkey roasting oven. I stir them once in awhile and after a few hours the beads have returned to their blue color, which indicates that they are dry and ready to go back into action.

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I like the concept. The engine folks think that this will keep dry air in and keeping the aircraft hangared is also a big plus from their perspective. They also suggest Camguard, which I use in my aircraft. It helps, too, that I fly each aircraft a lot.

Randy
 

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I built a dessicator system for my Cirrus with large diameter PVC piping, nalgene tubing, plumbing valves on either side of the PVC dessicator chamber, molecular sieve beads (the dessicant - buy them on the internet) and an electric inflatable mattress pump. It fits into a kid's toy wagon that I keep on the side of the hangar. I use the system when the engine is still hot and I am putting the plane up in the hangar after flying. I don't have a timer for it. I place a nalgene tube down the oil fill tube and then run the dry air into the crankcase for about 5 minutes while I am doing other things. Easy. Molecular sieves can be regenerated in an oven.

Another way to do this would be with plain ol' compressed air, because it is very dry also.

I am not sure how effective all of this will be, but I feel like getting all the combustion water and corrosive gases out of the crankcase before putting the plane away is sure not hurting anything. Between flights, the engine will "breathe" air in and out through the vent tube over time as temperatures and atmospheric pressures vary, but I'm hoping that this air will be nowhere near as humid as the air in the crankcase.

I am going to build another one for my Cub soon.
 
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Make sure if you slip this tube on your breather that you cover the syphon break otherwise you will be dumping the dry air overboard.

Kurt
 
Surprised no one else mentioned it.... fly more. 100 hrs a year isn’t bad, but at my maintenance shop the more an engine flys the less problems we see. At 100hrs a year your engine would calendar tbo before it does run time wise. Calendar time is harsher on engines than most people think.......

Could spend a lot of money on gadgets, or spend the $$$ on more gas to fly more.
 
My dad was an engineer for Mobil Oil, he explained to me that oil of any given viscosity had to have a distribution of molecule lengths to penetrate small openings(short) and long molecules to drain off surfaces slowly to protect from corrosion. These were the days before multivis oil (and before detergent, for that matter)...this was part of the rationale for STP, I had a friend who ran his 182 with STP, and had new limits the first tbo, and pretty good the second time. This was a geo survey plane, that sat for a month or two or more between hundred hour jobs.
*the other rationale was the zinc additive(zddp) which was an anti wear compound....
 
Yes, I put all the time on this engine flying about 2 hrs a week all year long. I think I will: 1. Add heat in the hanger to keep it 35-45. 2. Get the machine that you plug into the breather pipe when not flying. 3. Don't preheat with a oil pan heater any more. 4. Use 80 oil year round as it seems to me it is good from about 30 to 90 degrees startup. 5. Use Camgard. 6. What else?

Seems to me having a pan or other engine heater on all the time has a negative impact on engines but certainly not when used as preheat immediately before a flight when engine temps will continue to rise. Reading all of the comments also make me think that putting on an engine cover after all flights to slow the cooling process might have benefits at a low cost.
 
Leaving preheat on all the time almost certainly results in parts of the engine having cool spots. These will be the first to have condensation. If a Prop is one a large heat sink. So, I imagine a constant speed prop hub as just one issue with fighting moisture and corrosion if a heater is left on all winter.

The article in post #29 is worthy. A twin cessna owner monitors the temp and dew point inside the case of his engines using different methods. He posted what I think is real scientific data of whats going on inside the case after shutdown.
 
Corrosion is a chemical reaction. Absolute humidity ( moisture content) of the air and temperature are the determining factors. Cold and dry is good. Warm and dry is not quite as good, since warm air can hold more moisture. In my climate (arctic), heating the hangar would not be worth the expense. The outside air in winter contains so little moisture that I prefer to let things remain cold.
 
Corrosion is a chemical reaction. Absolute humidity ( moisture content) of the air and temperature are the determining factors. Cold and dry is good. Warm and dry is not quite as good, since warm air can hold more moisture. In my climate (arctic), heating the hangar would not be worth the expense. The outside air in winter contains so little moisture that I prefer to let things remain cold.
Good point. And every chemical reaction happens at a faster rate with increasing temperature. Seems the best thing would be to freeze-dry the engine after every flight. If so, I guess we’re looking for the second-best thing!
 
Maybe somebody should test argon or a similar dry, heavy gas. Inject argon into the oil filler to displace air. No more humidity. It could work.
 
Maybe somebody should test argon or a similar dry, heavy gas. Inject argon into the oil filler to displace air. No more humidity. It could work.
MaBell used to set nitrogen tanks to dry out phone moisture prone trunk lines in the pre-fiber days, worked wonders. They would purge at a high rate and then reduce to a maintenance rate for long term.
 
Nitrogen will accomplish the same result for a lot less money. "Noble" gases are expensive.


Maybe somebody should test argon or a similar dry, heavy gas. Inject argon into the oil filler to displace air. No more humidity. It could work.
 
I have nitrogen bottle in the hangar and several argon bottles in the shop. I may play with this idea as an alternative to an engine dehydrator system in a heated hangar. Like Kirby says you'd need some volume to purge but maintenance would require very little. To devise an automatic metering system would be the trick. They must exist somewhere out there.
 
MaBell used to set nitrogen tanks to dry out phone moisture prone trunk lines in the pre-fiber days, worked wonders. They would purge at a high rate and then reduce to a maintenance rate for long term.
So that's what those were for. I recall seeing bottles tied to the pole but never figured out why.
 
I can recall a certain airplane that sat outside in Fairbanks, engine heater plugged in all winter, engine cover on, just “in case” the operator needed to go fly. There were a couple winters where that plane didn’t fly four or five hours, if that. I figured that engine would be a pile of rust.

Then, I wound up flying it, for three or four hundred hours......great engine, and I’m pretty sure it went to TBO without any unusual maintenance. Go figure.

I can testify that these conversations have been going on for at least fifty years, and frankly, I’m not sure we’re any more knowledgeable on how to prevent engine corrosion than we were when I started flying. Of course, nowadays an engine overhaul costs more than most houses did back then.

The one pretty well proven method to prevent corrosion in an airplane engine: Fly the hell out of it.

MTV
 
I can recall a certain airplane that sat outside in Fairbanks, engine heater plugged in all winter, engine cover on, just “in case” the operator needed to go fly. There were a couple winters where that plane didn’t fly four or five hours, if that. I figured that engine would be a pile of rust.....

MTV
Mike, Isn't the humidity extremely low in Fairbanks, especially in the winter? I would think that the low humidity would take precedence over the temperature of the engine being warm. If there was very little moisture in the engine, what does it matter what the temperature is?
 
So that's what those were for. I recall seeing bottles tied to the pole but never figured out why.
Had a permanent one installed near my house for years and years, any time it rained big the phone got staticky so after a few years of watching I'd just walk by and turn up the regulator... worked wonders :wink:
 
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Mike, Isn't the humidity extremely low in Fairbanks, especially in the winter? I would think that the low humidity would take precedence over the temperature of the engine being warm. If there was very little moisture in the engine, what does it matter what the temperature is?

True enough, Pete, but I have seen several other engines in Fairbanks turn up significantly rusty......but I don't know how those engines were treated over a long period of time, other than I know they sat idle for a long time.

But, in any case, every time you run an engine, you wind up with some moisture inside the engine, regardless of the outside environment, due to water in the fuel.

You're right, though, if I were going to park an airplane, I'd rather have it parked in FAI than Orlando.

MTV
 
A good fellow on this website crafts a nice dryer which attaches to the oil filler port on the engine.

Basically, he makes a tube which is filled with a dessicant that is blue when dry and effective, pink when it needs to be recharged. An aquarium pump is utilized to pump air through a filter and into the bottom of the dessicant tube. The air exits at the top of the tube, through another filter. The tubing is connected to an attachment which then is affixed to a plug that is threaded to fit the oil filler port. He sets the timer to activate for a few minutes at a variety of times throughout the day.

Our engine gurus at Bolduc Aviation/Horizon thinks this to be quite helpful.

There is a different plug for each aircraft.

View attachment 44289
Note the small clear plastic observation port just below the exit point of the dessicant tube, which allows me to see when it is time to dry the dessicant. When it turns pink I simply take off the top of the dessicant tube, pour the dessicant beads into a bucket, take them home and put them in a turkey roasting oven. I stir them once in awhile and after a few hours the beads have returned to their blue color, which indicates that they are dry and ready to go back into action.

View attachment 44290

View attachment 44291

View attachment 44292

I like the concept. The engine folks think that this will keep dry air in and keeping the aircraft hangared is also a big plus from their perspective. They also suggest Camguard, which I use in my aircraft. It helps, too, that I fly each aircraft a lot.

Randy


Looks fairly simple. Do you have a contact/price on it?
 
True enough, Pete, but I have seen several other engines in Fairbanks turn up significantly rusty......but I don't know how those engines were treated over a long period of time, other than I know they sat idle for a long time.

But, in any case, every time you run an engine, you wind up with some moisture inside the engine, regardless of the outside environment, due to water in the fuel.

You're right, though, if I were going to park an airplane, I'd rather have it parked in FAI than Orlando.

MTV

Mid-winter, the ABSOLUTE humidity in the arctic is very low. The RELATIVE humidity, though, is very high,approaching 100 percent on many days. That's why we see ice crystals precipitating out of a clear sky, or ice fog that enshrouds the entire town when triggered by the moisture from chimneys, vehicle exhaust or an aircraft taking off.
It's the absolute humidity that causes the damage. A 'plane parked outside in Yellowknife or Fairbanks will suffer far less than one parked in New Orleans, summer or winter.
 
I can recall a certain airplane that sat outside in Fairbanks, engine heater plugged in all winter, engine cover on, just “in case” the operator needed to go fly. There were a couple winters where that plane didn’t fly four or five hours, if that. I figured that engine would be a pile of rust.

Then, I wound up flying it, for three or four hundred hours......great engine, and I’m pretty sure it went to TBO without any unusual maintenance. Go figure.

I can testify that these conversations have been going on for at least fifty years, and frankly, I’m not sure we’re any more knowledgeable on how to prevent engine corrosion than we were when I started flying. Of course, nowadays an engine overhaul costs more than most houses did back then.

The one pretty well proven method to prevent corrosion in an airplane engine: Fly the hell out of it.

MTV

My father put a factory new 0-360 on his 172 in 2005. He has a Tanis heater, cylinder and sump plugs. In the winter he would plug it in on a timer. It would come on every morning and shut off around noon. 15w50 aero shell and no camguard. He was mostly the only one flying it. That engine went to tbo last year. Couple hundred hours over. Only thing I had to do was replace the intake gaskets, they cracked and at almost 2000 hr on the nose the slick mags took a dump. Other then that zero maint. Never had to pull a cyl or anything. Got it overhauled this winter and it looked like new inside.


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My father put a factory new 0-360 on his 172 in 2005. He has a Tanis heater, cylinder and sump plugs. In the winter he would plug it in on a timer. It would come on every morning and shut off around noon. 15w50 aero shell and no camguard. He was mostly the only one flying it. That engine went to tbo last year. Couple hundred hours over. Only thing I had to do was replace the intake gaskets, they cracked and at almost 2000 hr on the nose the slick mags took a dump. Other then that zero maint. Never had to pull a cyl or anything. Got it overhauled this winter and it looked like new inside.


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~150-155 hours a year. That doesn't sound too shabby :D
 
Thoughts on the Engine Saver. It is hard to see the color of the desiccant in the supplied plastic bottle. So I replaced the plastic bottle with a glass jar. I then noted that the desiccant becomes saturated along the bottom of the jar first. Leaving 1/4 of the jar blue at the top of the exit end. Now when it gets to that point I roll the jar and it uses all the desiccant. Also, had the pump on the engine two weeks before doing a compression check that came out unusually low. ( did not pre run the engine ) Thinking that the constant low pressure below the pistons may push oil out of the rings. No big deal, just a thought. Jerry
 
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