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Stewbronco 11-20-2019 01:39 AM

Engine Dryer
Anyone got one of these in use ? Tried a couple of emails and phone call to order but no response... hope still in business as looks like a great product and neighbour at hangar has older version and it is great !
Thanks. Stew

Av8torTom 11-20-2019 09:26 PM

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.

TShort 11-21-2019 08:43 AM

I made my own, pretty cheap with parts from Amazon:

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.

rocketman1988 11-21-2019 09:49 AM

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?


TShort 11-22-2019 01:07 PM

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.




Hope that helps...

TShort 11-22-2019 01:08 PM

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.

David Lewis 11-22-2019 01:43 PM


Originally Posted by TShort (Post 1388198)
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.

TShort 11-22-2019 05:59 PM

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.

TimO 11-23-2019 10:08 AM

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.

RV7 To Go 11-23-2019 10:10 AM

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.

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