By (USUA #A86096)

It is April 15th in south central Pennsylvania, and it is raining like crazy, but I'm happy. Why am I happy it is raining? Because they were predicting SNOW - after Easter - just miles north of the Mason/Dixon Line! What gives? Anyway there's nothing we can do about the weather. Or is there?

We don't talk much about maintenance in this column because normally maintenance topics are pretty technical and require a lot of serious explanations and diagrams to fully explain it. But we have lucked out and have an article that allows us to discuss a very important maintenance consideration and allows us to do something about the weather all in one article.

The article comes to us from the Middle Tennessee Ultralight Group, or MTUG, from Murfreesboro, Tennessee and specifically from Barry Glenn, a member of that group. Barry reminds us that one of the major gremlins to attack our engines during the winter months when most of us do less flying than normal, is moisture. (That's where doing something about the weather comes in.) Moisture condenses on the cold engine parts and soon rusts these surfaces that were meant to be smooth and close fitting. Rust, the result of moisture allowed to sit on a metal surface, attacks cylinder walls, bearing surfaces, cam shafts (if your engine is so equipped) and just about anything else that you wouldn't want all rusted up and scared beyond recognition. If we could find some way of keeping the internal guts of our engines dry during long periods of non operation, we could greatly extend the life of all the parts that rust eventually destroys. One way of drying out a space is with a desiccant, the most common and inexpensive of these being "Silica gel". Silica gel has a great affinity for water and can absorb up to 1/4 of its weight in water before it becomes saturated. It can be regenerated for reuse by heating to drive out the water. Desiccants that change color are available so you don't even have to guess when yours needs to be heated to make it ready to suck up more water from the guts of your engine.

Now that we have located a material that will keep the innards of our engine dry, what is the best way of bringing this wonderful stuff in contact with the atmosphere inside the engine? The author has come up with a very simple and inexpensive method to accomplish this. You need a couple of those very large pill bottles that your month's supply of Potassium Chloride comes in. (Or if you don't have high blood pressure requiring that you take potassium chloride, just ask your local pharmacist to give you a couple of the biggest pill bottles he has in stock). You are going to need one bottle for each exhaust port and for each carburetor on your engine. (Single Carb would take one bottle for the carb and one bottle for the exhaust port. Dual carb engines will require one more bottle).

Now very carefully drill a half a dozen holes in the bottom of these bottles (maybe you should ask your pharmacist for an extra one in case you crack one during drilling.) Now cut a circle out of a Scotch Brite pad that will just fit in the bottom of the bottle (to keep the silica gel from running out through the holes you just drilled in the bottom), install the Scotch Brite circle and fill the bottle with Silica Gel.

Take your bottles to the hangar and install one bottle (holes facing inward) in place of each air filter on your carbs and one bottle on your exhaust outlet. The author recommends using a proper sized no-hub coupler to make this installation but a chunk of radiator hose or even some trusty Duct Tape can do the job for you. If you use the couplers, installation is easier and when the desiccant bottles are removed for flying, some rubber stoppers can be inserted to keep the desiccant from being saturated by absorbing moisture from the air while you are out chasing clouds. The author says that all parts required to fabricate this "keep your engine dry" system, except the pill bottles, are available from McMaster Carr Company at www.mcmaster.com and he provides the following stock numbers:

Or if you'd like to get the job done all at once with minimum effort, Marty Ignazito 13961 E Co Rd 620N Charleston, Illinois 61920 mdipe@consolidated.net 217-348-1525 will sell you a complete kit for dual Bing54s on 503 and 583 ROTAXs for $55.00 plus shipping.

I have no personal connection with any of these folks and don't stand to make a dime out of this suggestion, but it sounds as if saving an engine from the ravages of rampant rust is well worth the minimal effort required to fabricate one of these systems. And if a bunch of guys/gals got together and split the cost of the Silica Gel, the cost of the system when compared to replacing an engine is not even a consideration.

Before I send this to Hq for publication, Flying Club 1 sends us a 'heads up' about the Sky Vector web site located at www.skyvector.com which provides interactive (zoom in/zoom out, move right/move left, etc) reasonably up to date aviation charts for planning purposes. The site also provides airport information for a large number of airfields, to include small private strips. It does carry the mandatory disclaimer "Don't go flying with this website! Purchase a real chart, and come back alive to visit us again", but it is a nice place to do some preliminary planning or day dream flying. Thanks Club 1 for the info.

Summer is coming--fly often and fly safe....And remember the Prime Directive - Have Fun!