Hi gyus !

I'm flying a Wild Hare Edge 540t with a DA 50 and the last flight I made....the motor cutt of suddenly when I was in "harrier". The plane have less than 7 flight and firts deadstick. I'd like to know ALL the causes of the deadsticks and how to chek them..The RPM was too high..7200 at high speed...I was approximatly at 1/4 of throttle or less when the engine stoped..

thx Julien

(oil mixture is ok...I got a Zinger 22x8 and will change for a MENZ 22x8 as soon as it arrrives)

The one and only deadstick that I saw that involved a DA 50 was because the clunk came off the fuel line inside of the fuel tank.

Check your fuel system carefully. If it's still new and tight, you could be overheating it a bit too. I have a 22 x 8 MSC and turn around 6600 with a very rich break in setting. I'm currently experiencing the tale-lift and stall problem at idle rpms, but other then that the motor runs great.

Regards,
Lee

I have had 3 dead sticks on my DA50 ...

The first one the throttle servo lead came unplugged from the RX
The second one the ball link on the throttle lever failed
The third one, the Hitec digi-mini servo I had installed locked up at half throttle so I killed the engine with the kill switch and landed normally

Other than that.. hundreds of trouble free flights.

If the mixture is right and the fuel system in good shape these engines just run. I have not had any dead sticks because of the engine even once.

Awesome powerplant. Sounds to me like you may have overheated it or leaned it out. Richen the high end slightly (i.e. tune for max and then back off 200-300 RPM. Also , these engines LOVE a very lean low needle setting. They will get muddy and run too rich at midrange if the low needle is too rich.


DP

I've seen 2 deadsticks on the DA50. One was because the ignition wire rubbed against the sharp edge of the cowl, and failed. The second was due to a failed ignition module, which DA replaced under warranty.

Julien Hp, Did you try to restart it after the dead stick? If so what were the results?

No because I did a "hard" langing far away and bend the landing gear..so havent restart it...
I know the motor was kinda hot...
mayb overheating

I'll chek that

thx
jUlien

Check your voltage to your ignition. If you are useing lith/ion or lipo bateries and regulater your regulater could be bad. It should not put more than 6.8 volts to ignition without a load.

I cheked before the flight and on a 4.8 v batterie, It was 5.1 v with a load of 200 mah..mayb the batterie but....


juline

DP hit the nail on the head when he said the DA50 loves a very lean low needle. They will get VERY muddy at midrange if it's too rich on the low. I've found the best way to get the low "just right" is to keep leaning the low a little each flight until one time it actually sags while flying at 3000-4000 rpm range. Land, and open the low 1/16th turn. Now you got it. One more thing I'll throw in here. I've been running Mobil MX2T at 32:1 and just never could get my needles perfect. ie. no 4-stroking. I mixed a batch at 40:1, tweaked the low a bit, and it's never been better.....Flame suit on Dick and Ralph.

I run my sport gassers where they just barely transition...Anything leaner and the engine dies when the throttle is opened..If that's "very lean" so be it..[8D]
The high is set just at peak rpm and then backed off very slightly, not 4 stroking...
The racer 289 is set for 850 degrees F on the exhaust temp when wide open in the straightaway, low speed is not an issue..As long as it keeps running after a heat race anything goes, it's way rich on purpose to cool it off... Works for us.....

I would love to be able to read exhaust gas temps or head temps in flight........ Lots of talk here about 180 degrees........200 or so. I put my infered gun on my Stihl leaf blower during a 10 min full throttle run right at the base of the plug........310 degrees and running great. DA 50 is always 160 or so at the same spot after a full throttle run then landing.....sure it cools down some....

Nogyro-
I think these engines like running a little bit on the warm side, contrary to some thought.

Whats up with the greasy oil mixtures[:'(][:'(] ?

Ralph, did you leave your computer on at work again?

Well I had another dead stick today... crazy. The horrible connectors that DA supplies with the engines are too big for the size wire they are using.. so it vibrated loose while I was hovering. I was very lucky I was high enough to recover and land without incident.

I have been warned not to ever use those... well, I now know why.

Anyone running a DA engine would be well advised to eliminate that problematic power pole connector and either solder the connection or replace it with a standard (servo) type or deans connector like everyone else.

Not sure why in the world DA uses those crappy things... everything else about their engines are right on.

DP

Did the connectors come unplugged, or did the wire itself come out of the connector?

I too had a failure in this area, probably the same as desertpig.

The wire fractures where it is crimped into the Sermos connector, resulting in a deadstick.

This is easy to prevent. The whole procedure takes 5 minutes.
Disassemble the wires from the connectors.
Use heat shrink (4 pcs total) to strain relief the wire at the boundary of the crimp.
IMO, this is something that should have been done at the DA factory.
(And they insist you not mess with their connectors in the instructions)

Or just pitch the connectors, and replace with a Dean's connector assembly from the LHS.
Just make sure you heat shrink your solder connections for strain/vibration proofing.

Thanks for the heads up on the connector. I better get the cowls off my engines and check them out. I'm spending quite a bit of time TR'ing these days, not a good time for a dead stick. I've got 52 hrs on one engine, and 42 on the other.......

I have had two dead sticks with the DA-50. One was a receiver failure and the spring on the throttle closed it all the way. The other was a failed hall sensor or pick-up, the red thing bolted the crank snout. DA replaced this under warranty and I had the new one before sending in the defective one.

Sorry - I didn't describe the failure mode ... yes - the wire fractured at the conntector. The connector is way too big for the size wire. I got a PM from a few guys who say they have had the same exact thing happen to them! Ditch the connector and solder on a standard servo extension.. seems to be the best fix. The current running through the ignition is very low, no need for a deans connector.

Done!!

DP