i managed to get some more flying time in today. the winds were ok at around 5-15 mph. it was cloudy but everything was running good after flying for about 10 mins it was time to land and make a few small adjustments fuel and take off again after another 3 take offs we brought the plane in so i could take off one more time thats when everything went wrong. the take off was going well and the plane lifted off the ground when the engine cut out and headed for some cars at the field so instead of hitting them i turned the plane and made it back to the ground when it hit one of the logs that seperate the parking lot and the field. i dont know why the engine cut out. it was running sweet all day and still had gas in it. the firewall on my hanger9 xtra easy was pushed pack and so was the gas tank. the leading edge of the wing was broken but i guess with a few hours it will be ok to fly again. next time i will be replacing the mds 40 engine as it just seems to want to die all the time

It seems like you got off pretty easy damage wise. Before it was all said and done, I think the firewall and front end of my trainer had more epoxy than wood.

i still don't know why the engine quit the way it did but when i got to my plane it had no fuel in the fuel line. i pulled the tank out and noticed it had an 11oz tank which i thought was kinda big for a .40 engine so i have been thinking as the tank was so big it might not have been pressurizing correctly. but up until today this MDS engine has caused me nothing but trouble.

In my experience a engine that just dies has to be 1 or more of a few things...

***First and foremost If this happened after the crash check the clunk in the tank and make sure its not wedged forward in the tank from the impact!!*** If its OK Then...

I would first check for air bubbles in the intake lines. There could be a pin hole or cut in one of the lines. If there is air in the line, but no holes you should be on the look out for foaming in the tank. This is corrected by wrapping the tank with foam or something similar to absorb the vibration. Most engines run quite well at low speed up to half throttle with foaming issues. You don't even realize its foaming until higher RPM's. So the engine runs good then you take off and boom the engine dies.

After that I would balance the prop to cut out the rest of any vibration.

Check the fuel mixture and make corrections.

Then change the glow plug.

If none of the above apply.... well your gonna have a headache!

Keith

My guess is that you were running too lean. I don't think it means anything that the fuel line was empty--it's not unusual for the fuel to siphon back into the tank. And I don't think an 11oz tank is particularly large for a .40 size airplane. The way I was taught was to find where the engine performs best on the ground, then back off 2 or 3 clicks (i.e. richer). If you don't do the last adjustment, the engine leans out in the air, and as you found, take off is absolutely the worst time for dead stick.

An 11 0z. tank is fine. The standard is an 8 oz. tank for a 40 engine and an 10 oz. for a 46. It wouldn't hurt to go to a better engine. An OS or TT engine in 46 size would be a good choice. The 46 is pretty much the same price as the 40 but will give you better power in the wind and will work well when you move on to a higher performance sport plane. [8D]

I'm gonna agree with mike on running to lean,after you get it running to your satisifaction,have somebody hold the tx,pick up the plane and point the nose towards the sky,if it dies then it is definitly too lean.You want it to run a little rich if you have a full tank,as the tank gets emptier,the leaner it will run. *usually*
hope you get it going again.

If I bought new engine after every dead stick I would be bankrupt!

Now you know how MDS earned it's nickname, "Multiple Dead Sticks".
Dennis-

i know the engine was running perfect untill just before the crash. it had been set up by my instructor the week before using a tachometer and the day before i had it in the air for about 4 hours of flying without a problem. i did a lot of loops, rolls and tried to do a hammerhead which was funny to see it try. i just wish i could figure out what went wrong so i can use it as a good learning experience. but even my instructor cant understand why it died the way it did

Just because it ws set up right the day before doesn't mean it was ok the day you flew it. I am by no means an expert, but it seems I am adjusting on my engine about every outting.

I have seen other people tune there's up on every trip into the air,especially on days where the weather is unstable.

If your "low speed" needle wasn't set correctly it can die during rapid throttle changes. It might run OK when you slowly feed throttle in and out. But when you advance the throttle quickly (such as on take off) it can die.

Next time, before you fly, warm the engine up a bit. Then with the plane restrained let it idle for about 30 seconds. After idling for 30 seconds whack the throttle fully open. It should transition smoothly. If it doesn't, the low-speed needle needs adjustment.