I have a NIB thunder tiger .15 GP who refused to start .
I use OS 8 glow plug. The low speed needle valve was completly unscrew and i have no manual, so i set it to a half turn open .
Is there something wrong in my seting? main needle valve is at 2 turns
the engine is on a test bank and there is no problem with the fuel feeding.
engine is turning (or should be turning) at 8/6 APC.

I am at sea level and today conditions were ISA

Set the low end needle at 1&1/2 turns out, and the high
speed at 2 turns out. Remove the glow plug....put your
finger over the carb....and spin the engine with the
electric starter. You should see a "mist" of fuel come
out the glow plug hole. Put the plug back in, and the
engine will start right away.

Sometimes a new engine just needs a good priming.

Dave.

Well thanks for you suggestions, I didn't try with your suggested procedure yet, but what I may already tell is that when I finished yesterday with that F..... stupid engine, it didn't really need fuel anymore.
Fuel was litteraly pissing from all holes, and I experimented hydraulic locks.....

BTW I go to the LHS buy new glow plugs and I keep you advise

Ok, I got it after several atempts

engine finaly started with a Os A3 glow plug, the low end needle at 1-1/2 (thanks Dave) and the hig speed at 1/2 turn. engine is very rich at 1/2 turn. performed tree 8 ounce tanks breaking in and now the engine run his peak rpm with the hig speed needle valve at 1/4 turn......

should be a monday morning carb

....they are alot more fun when the engines runs, huh?

1/4 turn on the main.... sounds like it doesn't
have the correct needle in it. (too short taper), but
if it runs OK....don't worry about it.....

yes that's the most important !!! it runs

sounds like it doesn't have the correct needle in it


that's what I think also, especialy because mixture adjustement are very tricky, one "click" and the rpm change a lot


Yesterday I nearly experienced a eart attack in front of my test bank. It's a tentative of the guy who sell me the engine to kill me, I am sure

That's probably why it was flooding so bad at first.
Call T.T. Service center, and tell them about the needle
and they will probably send you a new one. Maybe even
a new carb.

I was gonna mention how touchy the adjustment on the
needle would be, like it is....but you already found out.
That wouldn't be the first time an engine came out of the
factory with the wrong needle in it.

Enjoy....Dave.

well it worked bad at first atempts because i was trying to find the seting to start by working from "open to close", this afternoon i changed my mind and made my first atempts to sart with 1/4 , and after 1/2 turn.

Hey Dave !!! we are overseas here, no toll free numbers to call with my bad needle. Will have to go to a LHS, compare my needle with a normal .15 one and then order one. The engine is new but it's a second hand purchase, so no way to obtain a free needle.

I'll go like that for first engines flights and if engine behaviours are correct it will stay like that

Yes, it will probably be just fine....
Let us know how the first flights go....

I don't take a big risk by making this approach of the problem, in fact the engine will go in a SIG WONDER, wich his per definition a DEAD STICK KING

one precision, all my work on that engine has been done with a chicken stick, it's maybe stupid but I use my electrical starter very rarely and I always try to break in my engines for easy hand start and long live

It also sounds like you are trying to turn too large a propeller on the 15. We ran several a year ago and found the 7-6 APC gave the best performance on a small light plane. Heavier planes required an 8-4 prop. If the engine is just breaking in it is best not to overload the engine with too much prop. Even a 7-4 works well for break in as the RPM can come up with out being too lean.