Model Forum / Radio Controlled / Air Models / August 2008

Ole' dummy here...I'm still trying to figure what a TT-.07 is. You said
trainer/07. What is a 07? Is this a very small trainer like a park flyer
with a small glow engine??
Thanx

Steve,
How to improve starting performance? Get a Miller 1/2A electric starter.

I also had trouble starting my new TT-07, flipping with my finger.   I gave
up the first day. The next time I tried, I was armed with a Miller 1/2A
electric starter.  The carburetor on this has an air bleed low speed
adjustment. It makes no difference where it's set unless your at the extreme
low end. I used a 6-3 prop and good 1/2A fuel(25%nitro and 25%oil). Using
the starter it fired right up and with a little adjustment of the high speed
needle it was running.  It did take a few minutes running before I could
begin to lean it out. Now it runs great. It not a real power house but it
does the job and it idles good for a small engine. The more I run it the
better it gets.

LGG

I'm not familiar with that specific carb but usually in an air bleed carb
you can see the screw in the hole. Count the turns from closed to open so
you know when you've gone too far. Start with it almost closed and work your
way out.
Hopefully other will chime in.
mk

If you are really talking about an air bleed screw, then it should not
bother the engine from running at wide open throttle, at all.

Run the screw in until the hole is closed, and back out (open) about a turn
and a half.  Open the throttle wide open (usual cautions; plane held, stuff
away from the prop, ect) and start it.  Bring it down to a fast idle, and
see how it sounds.  Adjust so it has a slightly burbling 4 cycle sound, and
then give it the gas, fast.  The throttle response will tell you what you
need to do next.  If it coughs and dies, close the air bleed.  If it
struggles in a 4 cycle sound and sounds like it is flooding, open the air
bleed.

Let us know how it goes.

A great little motor but hard for beginners to start until it is run in.
After run-in it is like a little sewing machine. NB: The manufacturers
instructions regarding run in and fuel mix are the optimum.

Standard starter motors do not spin over fast enough and will bend the
conrod in event of a hydraulic lock.

Easiest starting method is to build a 1/2A starter motor as shown under sub
section
"Cleaning & Starter Motors (Homemade & On board):
at Alan's Hobby, Model & RC FAQ Web Links
http://homepages.ihug.co.nz/~atong/

regards
Alan T.

------------

Unless gasoline carburetors (Walbro, etc.), model carburetors are not set to
a specific usable setting that is to be used when the engine is fired up for
the first time.

Why? Because the type of fuel, size of the prop and the height of the fuel
tank varies from one person/model to the next.

Close the high speed needle very gently. Don't screw it down tight or you
can ruin the carb internally. Just a little snug with your finger tips. Now
unscrew the high speed needle (the big one that sticks out from the side)
about 2.5 to 3.0 turns.

Adjust the airbleed screw so that the screw blocks 1/2 of the hole. That is
a good starting point for any engine, even the TT .07 (Yep, I have one too).

The big secret to running glow engines is to never try to run them without a
propeller or other load mounted on the crankshaft. Running them without a
prop or other load will instantly destroy the engine.

Use the manufacturer's recommended prop size. If you do not have that prop
size, do not run the engine until you do.

Use the manufacturer's recommended fuel. This is important.

This is a fine little engine, but you will have to learn its quirks. Once
mastered, you will be very happy with it. Be patient and do it right.

Ed Cregger