I wonder if it will be a smart move to start my brand new DLE 55 this weekend when we expect 29 - 31 F temperatures.
Any suggestions ? Maybe using synthetic oil ?

Thanks

The engine will be fine. The problem is . . . Can YOU take the cold weather?

Actually that's ideal break in temperature for a gas engine. It will be very happy. In fact it would be happy in that temperature all its life. You have to richen the needles quite a bit to fly in those temperatures. I'd say a 1/4 turn more rich on both needles. That's what I found out from flying in snow:

Just make sure you allow the engine to really warm up before you go crackin the throttle or you'll be replacing bent rods.

Very good advice.

HI
BEEN told that lighter fluid works well to start an engine in the cold weather ( car , spray starter fluid might help ) i only fly in 50 degree or better weather i have had lighter fluid with me ,but never had a need to use it as my engines always have started just fine at those temps BEST REGARDS TONY

This is siomething we used to do when hand starting glow engines in cold weather.

I've never needed to do this with a gas engine.

Yeah gas engines start just as easy in cold weather....as long as you richen the needles for the cold dense air.

No small 2 stroke engine likes to run if the engine temperature is below 80C - 100C. If you have a very cold engine and the pistons heats up faster than the case you have created the opportunity for a "cold stick" to occur. Hence the bent rod advice in an earlier post. Many of you running over snow will be starting and running an engine very near Zero C.

Better to take a heat gun and warm up the case and head before attempting a start. Once started you need to get the engine to above 120C for any appreciable "break in" to take place. Below that temp all you're doing is glazing the cylinder and preventing break in.

We used to call the "cold stick" a cold seizure. Same thing. I always warned my students flying two stroke powered ultralight airplanes never to make a long unpowered decent followed by an application of full power. That was almost guaranteed to cause a cold seizure as described by TOM. Of course applying a lot of power to any cold engine could cause the same thing, but hopefully we all know to avoid that. Low powered descents can also cause shock cooling problems with four stroke aviation engines.

We also used to have this happen with hot rod full size boats without an onboard contained cooling system if they went under a high power setting into a cold water area. The block would cool down and shrink, while the pistons were still hot from the load. The resulting noises and then silence were very expensive...

AV8TOR

I've run chain saws in Zero degree and below weather back in the 70's.

Bid thing is getting them started and slowly warmed up to where they sound OK.

Green wood cuts real good in very cold temperatures.

Worst wood is dead wood as it plugs up all the filters and dulls the chain in no time flat.

I would hardly know what it would be like to cut green wood. For the most part here in Arizona all you are allowed to cut is "dead and down" wood. Oak is great, mesquite is better, but pure hell on chains and bars....

AV8TOR

You can cut down, chunk up, and limb several green trees without getting the chain dull.

On a dead tree its three or four cuts through the trunk and you notice the chain beginning to dull. At my age, I begin to dull too by then

In recent years, I've cut up more dead wood than green wood. If you have a choice, stay with the green.

When looking at old saws, the one that was used on green wood will have a better engine

A cut off sock will work (using the upper part) to slip around cylinder too hold enough heat in to help your engine to warm warm up more even.. I would sure do that on a new engine. A cold breakin is just inviting trouble. The back of the cyl would heat up a lot faster than the front of the cyl. Depending on how cold it is ..with.the thickness of the sock in mind...mabye you could leave it right on the cylinder. Just note how warm it gets & adjust as needed. Kinda like In the winter I block off the air with cardboard on my truck. Just watch the temp gauge for good measure. Big deisel trucks as you know close of air flow too for more thermal efficientcy. Shoot I can,t spell to good.....I did have spell ck...now missing? Oh well close enough!

Capt,n

what is the point to break-in an engine in winter? It can not be used until the spring.

Black locust has the second highest BTU output when burned. Only some very long lettered Japanese tree is higher, but I forget which one.

If ya ever cut Black locust, take a slew of spare sharpened chains with ya. Just 3-5 cuts and sparks start flying! Extremely tough cutting wood!

For ultra cold winter running you can use a special self sticking aluminum tape to wrap the block and head. Simple tinfoil will do if you can assure security. Better know what your CHT's are all the time though.

Why not?

Because you may end up destroy the engine.

How cold does it have to be for this to happen? We usually fly during the winter, but I can't remember anyone telling me about damaged engines.

Maybe destroy is a heavy word. But in worst case, if u can not start it and keep spin it, the piston wall will get bad tear. The gas may not be present in the chamber to lube it up as the tiny passings in the carb could be blocked due to ice formation in the gas.

A couple posts back, some people also mentioned the rod could be broken.

Well no, it would be pretty unlikely for that to happen. If the gas freezes, it is only because it has water in it, and the engine probably wouldn't even run if it had frozen water in the carb.

What happens is that people rev the engine up and put a load on it before it has a chance to warm up. The piston grows quickly from the heat of the load, but the cylinder is still cold and contracted. This can cause cold seizures.

AV8TOR

My experience with chain saws when it is zero F, they will just not take the throttle until they are warmed up. Then they seem to run very well.

I'm not crazy enough to get outside with a model airplane to fly in less than 50F anymore. Flew some this fall in the high 40's by evening though.

I'll run engines in the garage door way when it is around freezing though.

Now if your radio system had on-board temp...you could moniter the temp & have a trim tab to open & close the air flowinto the cowl. Man that would be neat!!!! I used to fly in the winter.....years ago but that was with Glow engines. Off the lake in any direction...was fun if the sun was out a bit! Capt,n

And those planes would still be fun to fly today