RE: thunder tiger pros, help
 

I finally seemed to get the engine right.  It wouldn't stall, on the ground.  When I took it up, it cut out about 15 ft in the air.  It plummeted to the ground, safe.  Still couldn't figure it out since it was fine on the ground.  So, took it up again.  It flew alright for a few minutes but the engine cut out about 250 ft up in the air.  Deadsticked it safely, with a big bounce, but safe.<div>
</div><div>I'm just gonna replace the entire fuel tank, fuel lines etc.  It was a preassembled setup from the factory.  Might save some time simply by replacing all of the fuel system rather than troubleshoot it as per suggestion.</div><div>
</div><div>Fingers crossed.</div>

RE: thunder tiger pros, help
 

You may also be a little lean on your mixture?

RE: thunder tiger pros, help
 

Assuming you have the high speed needle set correctly, do the "pinch test" while idling. Pinch the fuel line closed. If the engine momentarily speeds up then dies, your low speed needle was too rich. If it dies right away, then it could be correct or a bit lean.

Another sign of a too rich idle is if you suddenly "gun" it from idle and it stumbles, it's too rich at idle.

I had a TT .46 Pro which I had a devil of a time keeping running. All my problems went away when I changed from 5% nitromethane to 15%.

RE: thunder tiger pros, help
 

The proper setting of the low speed needle is as lean as you can get the needle and the engine will still accelerate throttle.

That being said, the idle will still be a little on the rich side and will flunk the pinch test at idle.

RE: thunder tiger pros, help
 

After xchanging the fuel tank out, I took the escapade up for a flight.  It's a smooth flying airplane.  I was executing a loop when the engine cut, it was completely vertical.  Deadstuck it.  I fiddled it and took it up again.  Cut on takeoff 25 ft, and it dropped like a rock.  I was able to put it on the landing gear.  <div>
</div><div>You ever see those downhill skiiers who have such high vertical drops where their teeth/face smash into their knees?  That's how it looked after it landed.  The landing gear &amp; wheels bent into the wings, nicking it, leaving the landing gear bent flat.  This engine has been a source of frustration and fun.  However, it has deterred me from enjoying the escapade.  Anyone have an extra set of escapade landing gear?</div><div>
</div><div>http://www.scratchbin.com/images/pla...ntLandGear.jpg
</div>

RE: thunder tiger pros, help
 

Actually, I do have a set, but those you have will be fine after you bend them back into shape.:D

RE: thunder tiger pros, help
 

You haven't mentioned what fuel, glow plug, or prop you are running. My TT pro .40 was also a pain until a buddy loaned me his tach, which helped me set it properly. It was very sensitive to the slightest turn of either needle, much more sensitive than any Magnum or O.S. engines I've had. But once we found the sweet spot, it has run like a champ every since. I use 15% Omega fuel and #8 plug in mine. The prop also made some difference. That pro .40 will turn an 11 x 6 as fast as any of my .46 engines, but it loaded it up too much in transition from idle to wot. A 10 x 6 APC seemed to be its favorite prop. I would bet that your .46 would do best with a 10 x 6 or 11 x 6.;)

RE: thunder tiger pros, help
 

I didn't see props meantioned either. What worked my my 46 and my planes- APC 11.5x4, 12x4, 11x5
MAS 11x6

RE: thunder tiger pros, help
 

15% fuel, 10x6 prop  Definitely a finicky engine.  But I'm not giving up.  I will tune it, and it will fly.  Just need your help :)

RE: thunder tiger pros, help
 

It's either the tank or your trying to run it too lean.

Fuel that has set in the sun too long will do that too

RE: thunder tiger pros, help
 

My Thunder Tiger Pro 46 is my absolutely most favorite engine I have. You might want to pull it and try it on a test stand. Get it running right on the test stand then approach the running it on the airframe. I think one of the things I see guys do is test the engine in the plane while the plane is held near vertical. That test will tell you if you'll have problems in the air.

RE: thunder tiger pros, help
 

I know it's obvious, but I haven't seen it stated explicitly: you are using tank pressurisation from the exhaust?

RE: thunder tiger pros, help
 

Hi!
You are running it too lean!!!


Some advise... get rid of that big plastic spinner and that no good MA prop. A much better solution is to use a spinner aluminum nut and a 11x6 APC or RAM prop. 10x6 prop is too small for a .46 two stroke unless it's for a Q-500 racer type airplane. A 10x6 will rew around 15000 rpm which is not desirable.

Do not use a too big tank! Use a 240-300cc tank (8oz-10oz).
Mount it according to the tank rule!
Use silencer pressure.
Set the engine by ear! If you can not ...get help from a friend!
Use 5-19% nitro fuel! Anything more is just a waste of money!
Use an Enya 3 or OS 8 glow plug.

RE: thunder tiger pros, help
 

I just remembered last year I was having problems with my engine cutting out and it turned out to be the old syringe I was using to fill the tank, the black rubber piston had deteriorated from fuel and that black crap was blocking my filter. It was running OK on the ground but as soon as I got into the air, it would shutdown.

I do agree with jaka, use an OS #8 glow plug. On the expensive side, but it is the right choice for that engine.

Other things to check, is your clunk free to move inside the tank, also are all bolts on the engine tight so that you don't have a pressure leak?

RE: thunder tiger pros, help
 

Sledge hammered the landing gear back.  Not perfect, but usable.  
<div>
</div><div>After all the woes, I  believe I've finally figured out the problem.  It was all due to a poorly assembled fuel tank.  This tank had a leak which wouldn't pressurize the fuel properly.  I chased the problem in circles, high speed valve, idle speed valve, etc.  After I replaced the fuel tank with a new setup, I believed that I had fixed the problem.  The engine cutting this last time was due to running it too RICH.  </div><div>
</div><div>After I changed out the fuel tank, the idle valve was fine, however, my high needle valve was set up to run with the bad fuel tank, which wasn't pressurized properly.  It was running acceptably with the faulty setup.  Believing that the high needle valve was set properly, I flew her.  </div><div>
</div><div>Took a break during work and set the high needle valve.  Instantly I realized the problem.  Set it up using the pinch test.  Even lifted the engine vertical to see if it was flake out.  </div><div>
</div><div>Lesson learned, don't trust factory preassembled equipment.  Always inspect and verify for yourself that everything is working properly.  </div><div>
</div><div>Now on to more important business, enjoying the escapade, loops, rolls, and lazy flying.  Hopefully this is my last post on this thread.  Thanks for all your help.</div>