hi guys

what are the base settings for an MDS .40 engine?

Hi,
Sorry, the settings will depend on the fuel you are using, the enviromental conditions, tank position, etc.
I would suggets close the main needle fully clockwise, then open it about 2 turns.
The engine should start in this position but run very rich.
I can't remember the idle needle position.
If the engine is new, don't touch this needle. It will be close enough to get the engine running.
If you have moved it try this,
Close the carb until you can fit a pin in the opening and no more.
Put a piect of fuel tube onto the fuel feed nipple.
Blow into the fuel tube.
Adjust the idle needle until you can hear air flow.
I can't remember this completely but you should have air flow at this setting and no more.
Now when you open the throttle the air flow increases quickly.
This will be close enough to get the engine started.

Hope this helps,

Same as Big Feet except close the main needle, then open it 3 turns, THEN it should run rich...Should be enough to start it anyway,better to start too rich than too lean....Rog

the idle speed needle hasnt been touched, only the High speed needle,

so would 3 turns be alright?

and also, will i be able to run enya #3, OS #8 or Nova C6 glow plugs?

True, fair point. Totally agree. If it will not start, creep in a few clicks at a time until it starts.

When you have the engine running on which ever plug you use, if the engine runs well then stick to that plug. If it will not throttle up even when tuned well, or give you a good steady idle, then try a different plug.

I have a mds 40 at an elevation of 4500 ft or 1371 meters. I have mine dialed in at about 3/4 of 1 turn. I started with two full turns but it was always sluggish so I turned it back and now it works great.

Well yeah, higher elevation means less oxygen (air) available so you want less fuel to get the same mix ratio. The previous recomendations are good from sea level thru about 1000 feet.

What % nitro are you using? I had a MDS 68 that gave me problems with the stock plug and 15% CP fuel, after reading what others had recommended I switched to 5% fuel and a Fox idle plug and the engine came to life.