Engine-dryer-kit

Continental and Lycoming typically rate their engine life from 1600 to 2000 hours of operation
between overhauls on most models.   However, the only owners likely to achieve that kind of rated
performance are those who use their aircraft on a nearly daily basis. Why? The reason is not the
flying. It is the parking!
A primary culprit for premature aircraft engine overhaul is corrosion caused by condensation within the
engine cavity that occurs after shutdown. Aircraft engines that are used daily frequently reach their
rated TBO because liquid condensate is boiled off on a regular basis. Low use rate often results in
reduced engine life.   As the engine cools and the internal temperature drops below the dew point,
liquid moisture condenses out of the vapor and clings to internal engine surfaces. This liquid water then
resumes its ongoing process of eating up your engine from the inside out. However, if the dew point
can be made sufficiently low, then liquid water will never form.   The engine dehumidifier provides a
continuous positive pressure injection of extremely dry air on a 24/7 continuous flow basis. Any
moisture in the crankcase air is recovered from the blow-by vent and returned to the dryer. Passing
over the silica gel removes any residual moisture. When the desiccant saturates, the humidity sensing
electronics turn off the air pump, turns on a heat lamp in the desiccant and opens a purge valve to the
outside ambient environment. The desiccant is heated to ~ 200 F . As moisture is driven of the
humidity falls and the electronics restart the engine drying process.

Bill of materials for the automated dryer kit

(Original kit components)
Air pump
Tygon tubing 10 ft.
Engine air inlet connector. (brass)
Air stone (dust filter)
1 lb desiccant         AGM Clay CaSO4

Lid drill pattern template
Purge valve housing
¾” Silicon SCUBA check valve
Valve linkage   3/32’ brass tube
& Aluminum lever linkage
PC mounting rt angle 4-40 (2)
60W lamp
Lamp socket
Hollow lamp socket bolt
(1/8 pipe & nuts)

120V Power outlet (split)
Power cord flying lead Q100-ND
3/16”Brass tubing    1” stub inlet tube
3/16”x 7” Brass tubing delivery tube w/
Humidity sensor* (custom design)
All electronic components including:
120VAC to 12VDC power supply module
PC Board humidity controller
       LM555 timers (2)   .
LM358 Op –Amp
       HRF3205 FET transistor
       DPDT relay* (12V coil)
               K10P-11D15-12
       Resistors
3.6K
100K
39K
10K
6.8K
1K
Select resistor
100 ohms
Capacitors
       0.01uF
       0.1uF
       *Humidity sensor BARC

Full complement kit (all components)
Price $95 Plus $8 Shipping
Order from: www.barkeraircraft.com

For those who built the original kit, a partial kit is available without
the air pump, Tygon tubing, silica gel , Delrin cap and the brass air
fitting for the aircraft oil filler cap.
Price for the partial kit is:
$80 + $8 S& H
Order from: www.barkeraircraft.com

You will need:
Soldering iron
Solder
RTV glue
                Hand tools
Fabricate your own air   return adapter