Filthie's Mobile Fortress Of Solitude

Filthie's Mobile Fortress Of Solitude
Where Great Intelligence Goes To Be Insulted

Monday, 8 October 2018

The Dilemma Of The Two Cycle Stubfart

I don't get it.

Mmatt has no problems whatsoever getting his ultralight airplanes started in cold temps. Used to be that all snowmobile engines were two cycle and most of them started up like a hot damn in winter - and variants of those engines are hard at work on small aircraft today. So - stick a pin in that.

Yesterday my timing was finer than that of any farmer, and right up there with a swiss watch: I fired up my lawn mower and weed whacker for the last cut of the year. The mower needed a few extra pulls to get going - but so did the two cycle weed whacker. I had to run it up and warm it up before it ran right. Stick a pin in that one, too. It snowed overnight so an old goat can't cut it much finer n' that for timing, eh? HAR HAR HAR!!!

Now then - let us consider all that about all this:

I want to get my small RC planes on skis and run them in the snow all year round. The reason for that is the retired old farts at my field all migrate south for the winter and with them not around to hog the field - I can fly whenever I want. The only problem is that the small glow engines HATE cold weather. They start getting very balky at around 0C. I gave up on it when life demanded my attention elsewhere. But now... the flying itch is back in my blood and I feel the need to partake of the cool, green delicious fuel these toys like to guzzle.

Why is it that some two cycle engines will run in the cold, and some will not?

The secret, I'm told, is to get the engine warm. The problem with my glow engines is getting them to run long enough to warm up. I convened an academic symposium on the subject on the RC forum, and the intellectuals there turned their formidable intellects on the issue. The boys are saying that in cold weather, run the hottest glow plugs I can buy. Also, more nitro is better for the obvious reason that it will burn hotter. Most a that I coulda figgered out myself... but this is a new one: the boys said a great starter fluid for glow engines is …. lighter fluid!

Harumpfffff! Call me a skeptic: lighter fluid comes out somewhere around diesel in the burn characteristics if I recall correctly. But the intellects of RC academia were adamant, not only would it work, some said, it worked so well that it should be cut with regular nitro fuel. Other said a few drops down the carb wouldn't hurt nothin' and that that's what they did.

Interesting experiments are in the offing. If any of you have any advice to offer, the comments are always open.

Have a great Monday!


  1. One of these?
    Or a jury rig a small one of these,

  2. Yup, great minds think alike Jon! I have a heat gun I will drag out too...

  3. Don't look at me. Every single time I've had to screw around with a two cycle engine, I want an electric starter and my profane creativity astounds the neighbors - in a quarter mile radius. It could be the middle of August during a heat wave, and the blasted two cycle won't start.

    I hate two cycle engines. Hate 'em.