The $47 Dollar Electric PreHeater

Last week the Seattle area became unseasonably cold. During the past three years that the 7-Oh-Fun has been flying we had not seen temps in the 20s.

Disclaimer: No warranty is implied and no liability is accepted. This sort of preheater will require supervision. Do not leave unattended.

What to do? If necessity is the mother of invention, then the Lowe's next to the airport was the father.

I found  the following cheap items:

  • UtiliTech Cermamic Electric Space Heater ($25 electric heater, Item #485219)
  • Plastic vent ($5, Item #328910)
  • Flexible vent tubing ($10, Item #40529)
  • Aluminum tape ($5, Item #433282)
  • Tube spring clamps ($2, Item #55597) 

Here are all the parts before assembly:

After unpacking the parts I took the aluminum tape and masked off the sides of the heater to prepare for the vent being attached.

I then removed the louvers from the vent and taped it with the aluminum tape over the heater with the round tube adapter pointing out.

Finally I used the clamp to attach the tubing. Towels were used to plug the front of the cowling. The free end of the tubing was inserted into the lower rear area of the cowling. The oscillation feature of the heater was turned off. 

You can also see that I used a VERY low powered hairdryer pointed at the oil tank to assist.

The heater was adjusted to be "not too hot" with the fan on high. The whole system took my oil and engine from 24F to 48F in about 30 minutes.

Good luck!

Load Previous Comments
  • Jesse Hartman

    So I just looked at the ACS heater for the rotax....... 400.00   WTF are you kidding me.

  • Louis W. Ott

    I use one of these heat pads on the bottom of my Corvair oil sump. It warms the entire engine after a while. Either control by thermostat or leave it on all the time when its cold out.

    http://www.amazon.com/Kats-24100-Watt-Universal-Heater/dp/B000I8VL3...

  • John Austin

    Just one word of caution on all pre-heaters adapted from room electric heaters, hair dryers, etc. I had a cousin who was an engineer specializing in custom industrial air management. He told me that all the common residential heaters and blow dryers' fans and motors are not designed to "push" air against resistance from ducting not in the original design. Therefore, be very cautious in the length and diameter of your flexible ducting so as not to create too much resistance. I would not recommend running a home-made design unattended unless it has been thoroughly tested.

    By the way, those "Hornet" aircraft heaters are excellent, safe, and pricey! I bought an identical heater from them for an "enclosure" rather than an aircraft and it was less expensive. However, they seem to be coming out with new models all the time.

    John