My DA50 can only run about 2-5 seconds when start warm, say 5 minuets after 1st flight of the day. It then dies. It behaves like that recently. Cold start is always easy.

The engine has seen about 10 gallons, after break-in. I am using 90:1 armsoil 100:1 premix. THe fuel line, inline filter and the mesh filter inside the carb are free of debris.

I also noticed that the low idle trim has to be pushed up (= more air) about 2-4 clicks for the engine to idle at ~2000 rpm.

Any suggestion?

Thanks --qc

The low needle valve may be set to lean. You can try to open it 1/16 turn to see if it helps?
Dan

i had the same problem. it might be interesting for you to check my post out. http://www.rcuniverse.com/forum/m_4089701/tm.htm
few things that i changed to make the problem go away.
1st the fuel tubing was very loose. tank to the clunk and clunk to the carb. i think there was an air leak there.
2nd i changed the ignition battery, from an old 4.8v 1500mah to a new 6v 2300mah.
3rd i changed to pennzoil from castrol.
i don't know exactly what helped but my engine wouldn't start hot at all and it would stop mid air after about 5mins, now the engine starts hot or cold after a few flicks
hope this helps

Mine ususally starts on 1-2 flips when warm

Hi Josey,

Can you tell us what kind of fuel you are using? What type of ignition battery? And has the engine been upgraded? Thanks --qc

Both engines are updated..Both run on regular gas (87 octane)..2400 Fromeco Lion set to 5.0

one has 25 gallons thru.. 4 with lawnboy 32:1 ...21 with Amsoil 100:1

the other has 2 gallons of Lawnboy

The battery change provides some hint. I recycled the ignition battery several times before today's flight. Looks like it helps as I can start the engine three times when it was warm.

As the heat trapped inside the cowl can affect other components (ign module, and/or carb in particular), I would think the ig. module definitely plays a role.

Have called DA last week explaining the problem. Their recommendation is to send it in for potential upgrade. Do not know additional potential upgrade is necessary other than the fuel line one (into the carb black block, instead of the engine body). Any idea?

Hesitate to send it in because afraid of loosing flight time. The weather here is perfect for fly (80 degree, calm wing).

--qc

I think I solve the mystery by removing most of the wrapping foam. I only keep a piece between the module box and the firewall. The engine starts in 1 flip, regardless of it being cold or warm. Looks like the wrapping foam prevents the heat to dissipate from the module.

Updated 5/13/2006: had 5 trips to the field since the "reinstallation". The hard to start problem never occurred since!

--qc