After several flights this winter and the large fluctuations in temperature I have seen moisture on the floor or on the belly of the aircraft that has come from the breather tube. When I am preheating and the temp gets up I can see some moisture drip or some light brown milky looking substance streaking down the belly. The good thing is that I am getting the moisture out by flying but it got me thinking.
There are several home made units that you can make to put in the dipstick to push dry air in. What do you guys have out there?
I am thinking about this unit I found out about at www.enginedryingsystem.com. Really neat videos and the info looks interesting. Any thoughts? Is there data out there that shows keeping as much moisture out of the engine does prolong the life of your engine if you can't fly every week?
Waste of money?
Thanks
Brad
Engine Drying System
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
-
hilltop170
- Posts: 3481
- Joined: Sat May 06, 2006 6:05 pm
Re: Engine Drying System
The methods mentioned above will do the job of drying an engine but if there is not any power available to run a powered system, simply removing the oil filler cap right after engine shut down will allow warm moist air from inside the crankcase to naturally escape by convection. The warm moist air leaving the engine will be replaced by cooler ambient air entering thru the engine breather. Maybe not as positive ventilation as a powered system but better than leaving the engine bottled up full of warm moist air with no way to vent.
Richard Pulley
2014-2016 TIC170A Past President
1951 170A, N1715D, s/n 20158, O-300D
Owned from 1973 to 1984.
Bought again in 2006 after 22 years.
It's not for sale!
2014-2016 TIC170A Past President
1951 170A, N1715D, s/n 20158, O-300D
Owned from 1973 to 1984.
Bought again in 2006 after 22 years.
It's not for sale!
-
ptporebski
- Posts: 72
- Joined: Tue Jun 08, 2010 10:34 pm
Re: Engine Drying System
Brad,
I live about 7 miles from the Gulf of Mexico in West Central Florida and have the same constant low dew point spread that Aryana probably does.
I built a silica gel based engine dryer from:
1. A plastic pretzel jar that my wife bought (and I ate all the pretzels from.
)
2. 20 pounds of 3mm silica gel beads that I bought. You want the blue indicating type that turn pink as they absorb water.
3. An aquarium air pump and misc tubing
4. A lamp timer
5. A janitor's polisher floor pad that I cut up into filter media
6. PVC pipe fitting that i use as a diffuser to hold the gel an inch off the bottom of the pretzel jar where the air comes in and allows the air to go thru the entire gel column. It functions something as packing does in a column.
7. Two pet shop terrarium temp/moisture gages.
Basically, you run the pump off the timer, push the air thru the silica gel, and into the engine either thru the dipstick tube or get a second oil cap and drill and fit it for a nipple to attach the air tubing to. Total cost of everything was maybe $30 certainly less than $50. Here in Florida it keeps the air at anywhere from 7% RH up. I change the gel out monthly and by then even in summer it is only up to 40% RH. Timer is set to run the pump for one hour twice a day in our dry season and four times a day in wet season. I use wife's oven set as low as it goes (170F) to regenerate/dry the gel by spreading it out on a cookie sheet. She objected until I showed her a MSDS for silica gel. It is totally inert, doesn't have any smell, and can be swallowed without any affect. It is basically just sand. I use 5 lbs of silica gel at a time. That was the reason I went crazy and bought 20 lbs. That way I have a couple of extra months if I get lazy and don't dry it out immediately. BTW - need to be careful when drying the gel. I used to use a cheap crock pot but it got too hot even on lowest setting and ruined my gel. It cooked the beads at about 210F.
I am using the dryer on my Cessna Cardinal (177B model) that I am redoing the interior and panel on. I don't expect to have it back in the air until later this year. In the meantime I fly my 172 several times a week to dry that engine out
.
If you want I can post a couple of pictures of the home made dryer. It wasn't hard to make and does the same as the $500 dryer.
I live about 7 miles from the Gulf of Mexico in West Central Florida and have the same constant low dew point spread that Aryana probably does.
I built a silica gel based engine dryer from:
1. A plastic pretzel jar that my wife bought (and I ate all the pretzels from.
)2. 20 pounds of 3mm silica gel beads that I bought. You want the blue indicating type that turn pink as they absorb water.
3. An aquarium air pump and misc tubing
4. A lamp timer
5. A janitor's polisher floor pad that I cut up into filter media
6. PVC pipe fitting that i use as a diffuser to hold the gel an inch off the bottom of the pretzel jar where the air comes in and allows the air to go thru the entire gel column. It functions something as packing does in a column.
7. Two pet shop terrarium temp/moisture gages.
Basically, you run the pump off the timer, push the air thru the silica gel, and into the engine either thru the dipstick tube or get a second oil cap and drill and fit it for a nipple to attach the air tubing to. Total cost of everything was maybe $30 certainly less than $50. Here in Florida it keeps the air at anywhere from 7% RH up. I change the gel out monthly and by then even in summer it is only up to 40% RH. Timer is set to run the pump for one hour twice a day in our dry season and four times a day in wet season. I use wife's oven set as low as it goes (170F) to regenerate/dry the gel by spreading it out on a cookie sheet. She objected until I showed her a MSDS for silica gel. It is totally inert, doesn't have any smell, and can be swallowed without any affect. It is basically just sand. I use 5 lbs of silica gel at a time. That was the reason I went crazy and bought 20 lbs. That way I have a couple of extra months if I get lazy and don't dry it out immediately. BTW - need to be careful when drying the gel. I used to use a cheap crock pot but it got too hot even on lowest setting and ruined my gel. It cooked the beads at about 210F.
I am using the dryer on my Cessna Cardinal (177B model) that I am redoing the interior and panel on. I don't expect to have it back in the air until later this year. In the meantime I fly my 172 several times a week to dry that engine out
.If you want I can post a couple of pictures of the home made dryer. It wasn't hard to make and does the same as the $500 dryer.
The better is the enemy of the good.
1959 C-172
1959 C-172
Re: Engine Drying System
I would love to see some pictures. Just the information I was looking for. I knew there were plenty of people smarter than me.
Thanks
Brad
Thanks
Brad
Re: Engine Drying System
Seeing that the picture of the airplane on the dehumidifier shows it equipped with a "Donkey Dick" exhaust, it makes me wonder if maybe the promoter of this gadget isn't enamoured of gagdetry.
BL
Re: Engine Drying System
An engine which is shut down after a flight is HOT...and the oil is presently ALL OVER EVERYTHING inside the engine, thereby helping to keep moisture from rusting anything needful of short-term protection. Long term protection is provided by frequent operation.
The ABA promotes the idea of opening a top-mounted oil filler cap to allow hot vapors to escape a recently shut-down engine, but I'm not convinced that allowing the hot air out the top.... doesn't introduce moist atmospheric replacement air into the crankcase from the lower breather tube, and I don't want to leave my sump cap open for storage.
In almost 50 years of flying I've yet to lose an engine to corrosion, and I simply shut it down and perform a proper post-flight.
The ABA promotes the idea of opening a top-mounted oil filler cap to allow hot vapors to escape a recently shut-down engine, but I'm not convinced that allowing the hot air out the top.... doesn't introduce moist atmospheric replacement air into the crankcase from the lower breather tube, and I don't want to leave my sump cap open for storage.
In almost 50 years of flying I've yet to lose an engine to corrosion, and I simply shut it down and perform a proper post-flight.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
Re: Engine Drying System
I just have to admit that I'm one really lucky guy. I'm no longer flying, but I went along for a good many years, on a number of various aircraft engines from the arctic to the tropics, and I NEVER had a crankcase dehumidifier. I don't remember ever finding any rust on the inside of an engine either. But then, I never had one of those "Donkey Dick" exhausts either.
BL