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Engine Dryer

Engine Saver

I have and use the Engine Saver available from Aircraft Spruce. My engine has not yet been run and so I have desiccators in the upper spark plug holes. I used to have to recharge them about once a week. Since using the engine savor I haven?t had to recharge them since June. I?ve recharged the desiccant in the Engine Saver twice since June. A LOT of piece of mind.
 
I made my own, pretty cheap with parts from Amazon:

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One plug in the oil filler, one in the breather. You have to plug the "intake" in the aquarium pump to make it a closed circuit. I put a filter on the end of the tube in the desiccant bottle to keep any silica out of the engine.

I've had it in use for 2 years, just now regenerated the silica beads for the first time.

There is a fair amount of moisture in the tubing when it is first connected after shut down.
 
engine saver

Do you have a sketch of the plumbing on your homemade rig?

Also, do you plug the intake and exhaust when the dryer is running?

Thanks
 
I don't have a drawn schematic; links to parts below.

Pump pulls air from top of beads (through filter on end of tube in the container), into a hole drilled into the case of the pump. Filled the intake on the pump with caulk. Output goes to oil filler, return from breather goes into bottom of silica bead container.

I went cheap, didn't buy special containers etc and used old scrap wood. The oil dipstick fits perfectly into 1" PVC via a PVC junction. The old ice cream container (brown lid) is for storing the rubber plugs when not in use. They get oily, this keeps dust off so I don't contaminate the filler tube when reinserting.


Pump:
https://www.amazon.com/gp/product/B004PB8SNQ/

Beads:
https://www.amazon.com/gp/product/B013L2Z2MY/

Stoppers:
https://www.amazon.com/gp/product/B00ES3UE9C/

Hope that helps...
 
Good question on plugging the intake / exhaust; I have not been doing so. I'd be interested in thoughts on whether it would make a big difference. I certainly don't hear any air leak / movement when I listen at either spot. I suppose having the throttle closed counts some for the intake. The aquarium pump isn't moving huge volumes, either.
 
Pump pulls air from top of beads (through filter on end of tube in the container), into a hole drilled into the case of the pump. Filled the intake on the pump with caulk.

I love your solution. I've seen other references to the aquarium pump inlet needing to be plugged, but don't understand the reason. Can you provide the explanation for this requirement? I want to make one of these.
 
Plugging the inlet makes it a closed loop system - the pump just continuously circulates air through the engine and media.

Otherwise you?ll pull ambient air in, making it much less efficient in terms of circulating, and adding humidity from the hangar.

This model pump has the intake on the bottom.

I used it for 23 months before the beads turned pink ... and it?s pretty humid here in Indy.
 
Question for those who are using the engine Dryers:

Do you just leave it run 24x7 or do you switch it on and off. I know that some models that you can purchase come with humidity sensing, which would be nice but is an added complexity and cost and I don't really care to go down that road.

I'm thinking that if you run it for an hour after a flight and then maybe 10 minutes out of every hour, on a closed system, it would probably work out just fine, but air leaking in the exhaust valves and elsewhere could void that theory.
I would run it 24x7 if I can ensure a closed system with maybe capped exhaust and intake, but capping them both adds more to the connection routine too and is harder on the RV-14 with the intake up in the nose inlet as a square filter.
So if you can't easily cap it all, it may be best to just keep the positive pressure of a 24x7 flow.

I just finished building and connecting 2 of them, and each one has 128oz worth of dessicant in it, and it's in clear bottles so it'll be easy to see when it changes. I just don't have any experience in how long it'll last in my environment. I'm sure it varies greatly by where you live.

One other notes: I wanted to do a closed loop on both planes, so I feed it in the oil cap and out the breather, but I found that the 2 planes have different sizes of both. The RV10 IO-540 uses a drilled #7 stopper on the oil inlet where the IO-390 uses a #6, and the RV-10 breather is a #4 drilled stopper, but the RV-14 is smaller...guessing #3, so I need to order one of those before I have that one looped. I just mention this because there was a definite variation and so advice about one engine may not quite be the same for another engine.
 
I made a similar drier years ago based on an article in an EAA magazine. Just an aquarium pump from the pet store, a 1.5L soda bottle, Tygon tubing, fittings and indicating Silica. I use round plastic pill bottles to cap the exhaust pipes. Dry the desiccant in an oven at 240F when it turns pink (some guys on the field use a microwave, or a crock pot on high). Been doing this on 3 different planes over the past 15 years.
 
Tim-

I leave mine on 24x7. I connect it right after I push the plane in the hangar, and then just forget about it. I agree, I don't think the added complexity is worth it.
 
Thanks for that. I decided to just do as you do and go 24x7. I may as well see how long the desiccant lasts right away. I purchased enough extra to change it out and bring home the used to bake off, so it's not going to be too much heartache if I have to regen it monthly. I found out tonight that my RV14 probably needs a size 0 stopper to fit in the breather, which is smaller than I thought. In my experimenting, I ordered a whole bag of various sized stoppers, so today I ordered up a cork/rubber stopper boring set on eBay. Never had to use one before, but wish I would have had one in the past. Apparently the way to drill holes in thick rubber is to use a sharpened piece of tubing to drill through it. They actually sell those in sets of various sizes. I figured what the heck, I already own the stopper I need, so I may as well get the tools. Any excuse to buy a new tool, right? I'll post a pic of what I built sometime after i get a chance.
 
Tim,

You will find different sizes of both dipsticks and breathers. Just have to see what you have and build one accordingly.

Some of the guys on the field have built them with a hygrometer inside a sealed box on the return to the pump. I was never a fan of this as I don't think it senses the moisture level in the crankcase properly, unless you put it on a timer to run it periodically. I personally like the KISS theory and just run it 24/7.

In the Toronto Canada area my 1.5L bottle lasts about 3 weeks in winter and 1 week in summer. I don't recirculate at the moment, just run it into the dipstick tube and out the breather with the exhaust pipes capped. I also wait about 15 min after a flight with the dipstick pulled, to vent some of the vapours out of the crankcase, before installing the drier.

When I was doing it recirculation about doubled the time before drying the silica. It also gets engine fumes absorbed into the silica, so don't dry it out in the oven at home or the wife may have something to say! Ask me how I know....
 
aquarium pump engine drier

About 15 years ago, I parked my 182 because I found magnetic particles in the oil and didn't have the money for a tear down. After a year or so, I became concerned about corrosion and bought an aquarium pump at Mal-wart, ran the outlet thru a liter of laboratory drier (Drierite as I recall) that I had laying around, and from there thru a small particle filter into the oil filler. I didn't plug the intake, but rather left the pump inside the plastic I wrapped the engine in.

With one thing and another (new roof, kids' college, etc.) I wasn't able to do the teardown for ~8 years. When I did, the parts of the engine beneath the pistons (cam, crank, etc.) were as shiny as new (metal turned out to be from a failed starter adaptor, which is a whole 'nother story). The upper cylinders had a "very light" coating of surficial discoloration (prob rust) that the IA honed off before reassembly. Its been another 4-5 years and 2-300 hrs on the engine since then with no indications of any problems.

I checked the dessicant for moisture ever month or so, but only had to change it 2-3 times in that whole period.

I understand the argument about closed loop systems, and can't argue about the theoretical advantages, but mine wasn't and it seemed to work, based upon the indicator in the drierite, and the condition of the engine when we reassembled it. Granted, I live in a fairly dry climate (6-8" of precip), and the pump was in the same contained envelope as the engine, but I had pretty decent results with this very simple method. It certainly beats the old procedure of wrapping an engine with plastic and throwing a pillow of silica gel in with it.
 
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