thunder tiger GP .07 problem
 

I have a new thunder tiger GP.07 rc engine that i bought from a person first the needle valve was broke i orderd a new one and installed it and now i am trying to start this engine for the first time i read the manual on starting and all i get is a light poping sound what can be the problem.this is a new engine new glow plug new fuel line and tank could use some help please

RE: thunder tiger GP .07 problem
 

Some of the folks in the 1/2a & 1/8a forum have experience with this engine... You probably wont like what they have to say about it though.

RE: thunder tiger GP .07 problem
 

I have one of these engines. It is currently on a 36inch wingspan model that I designed and built myself.

It is a lovely little engine, the model goes like a greased rat. It is reasonably quiet and starts easily.

However..... when it was new I tried hand starting it, for hours over a period of some days. Not a pop! (apart from a very quiet one from the exhaust outlet but no signs of a start )

In desperation I bought an electric starter... woohooo success !

I still use the electric starter to get it going. I use 10% nitro fuel with castor oil as the lubricant.

Just be carefull... it can easily be flooded with too much prime. Take care that it hasn't hydra locked before applying an electric starter.

After the initial run-in period and over several flights it has proved to be a reliable engine and I NOW like it :)

I have seen comments from others that it needed an electric starter to bring it to life so it wasn't just my engine that was being difficult, others have experienced the same problem.

The light popping sound you refer to sounds as though it might just be the noise from the silencer as the engine is flipped over, as opposed to an actual `pop' as it nearly starts ???

My other engines, including a TT .15 all start easily by hand, but not the 07.

Reg

RE: thunder tiger GP .07 problem
 

reg sence the needle was replaced can you tell me were to reset both needles from a fresh start maybe that mite help and thanks for the reply

RE: thunder tiger GP .07 problem
 

As a start just open 3 turns from closed, You really nead to crank this with a 1/2 A starter, at least for the first runs remember the coxs and other small engines used a spring to turn the engine over it just hooked on the prop and you wind it backwards then released it, you cannot hand flip an engine that quick and most likely the spring gave at least 20 turns
as quick as an electric starter martin

the 07 is not a very powerful engine bit should do ok in a light sport or trainer

RE: thunder tiger GP .07 problem
 

[quote]ORIGINAL: dieseldan

As a start just open 3 turns from closed, You really nead to crank this with a 1/2 A starter, at least for the first runs remember the coxs and other small engines used a spring to turn the engine over it just hooked on the prop and you wind it backwards then released it, you cannot hand flip an engine that quick and most likely the spring gave at least 20 turns
as quick as an electric starter martin

the 07 is not a very powerful engine bit should do ok in a light sport or trainer

the AP hornet 09 at $50 is twin BB, good carb and bushed rod, I have several and as matter of fact converted to diesel, they turn a 8x5 wood zinger at 11400
regardless it\f stock glow or diesel conversion its a great engine

RE: thunder tiger GP .07 problem
 

Matter of fact dieseldan i have been trying for hours useing a eletric starter and does not want to run. manual says 2-1/2 turns out on carb and it trys to start will run very low for about 5 seconds and thats it am about to drop it in the box and forget it all ready used a pint of fuel and still have the same no run problem thanks

RE: thunder tiger GP .07 problem
 

Mine was easy to start after I learned it loves a sloppy wet prime. Be careful of the hydraulic lock when doing this. It is a smooth, easy to use engine. Low on power and a little on the portly side.
Good luck, MikeB

RE: thunder tiger GP .07 problem
 

I had one that ran fine. Do you have the head wrench? Isaw compression leaks on mine and tightened it up and was ok. I always had a leak out of that small dimple on the back side of the cylinder, but sold it before I did anything about it, but it still ran like that. I am sure you have tried the needle valve in or out from your base setting.

RE: thunder tiger GP .07 problem
 

Thanks i will check that out and repost

RE: thunder tiger GP .07 problem
 

Hi,
I just checked my engine. The main needle is set at just 1 and a (little) bit turns out from closed.
I have never touched the slow speed screw as it was O.K.

If you have altered the slow speed setting then just ignore it untill you get the engine running at full throttle, you can then set up the idle speed and check transition.

I am using 10% nitro fuel and I find the needle setting doesn't have much leeway. I find that 3 clicks will be about as much as you can go before the carb starts going lean or rich and the engine threatens to quit.

I see you fitted a new needle. I reckon once you get the correct needle setting all will be well. I have not encountered a carb as sensitive as this, a couple of clicks either side of the ideal position and the engine will indicate it is not happy ! My other, bit bigger, engines all have a broader range of needle setting with 10% nitro and are nowhere near as sensitive as the 07 is.

As stated by someone else... the engine is not a power house, but it does run very nicely and also reliably when you get a few tanks of fuel through it.

I seem to remember I had to quickly alter the needle to keep it running after I managed to get it started as it would do the same as your's... cut out quite quickly.

Good luck

Reg

p.s. I would not use this engine without a fuel filter in line. It would be veryy easy to get a blockage .

RE: thunder tiger GP .07 problem
 

thanks reg real helpful

RE: thunder tiger GP .07 problem
 

Make sure plug is ok --step 2 disconnect the fuel line prime hit with the starter it should run for a short burst- if it does then put line back on start at 1 1/2 turns open if starts and dies open a half turn at a time till it stays running make sure you are wide open on throttle martin

RE: thunder tiger GP .07 problem
 

My magnum .15 sounds about the same, manual stated 2-1/2 turns out but this engine would only run at 5/8 of a turn out and is still running perfectly 1-1/2 years later at that setting. Since the engine is not running at all i would keep leaning it out until it does, also make 100% sure that you have a good glow plug with a FULLY CHARGED glow plug driver.

RE: thunder tiger GP .07 problem
 

I have tryed everything you guys mention at lease 5 times each the longest it has run was 7 seconds then it would not do it again and that run was a very low idle.i checked the head it was a little loose tighten it.I tryed the different setting of the carb from 3/4 turn to 2 turns i installed a new glow plug kept one off to the side just to check the glow driver for heat it was and is fine.I kept the setting were it has run best for what reason am not sure if something maybe wrong with the engine i was hoping it would hit and stay running but it does not look like it is going to. This has to be the hardest engine i have ever owned to get running and i have a few 1960s new engines that run and start easy.I do not want to give up on it but the time i waste trying to get this engine to run is uncalled for i want to thank everyone for there support

RE: thunder tiger GP .07 problem
 

I just read through the thread. Lots of good comments. Let me try a couple.

For one, if an engine doesn't start quick, I usually figure I've flooded it, and walk away for a few minutes, check air in my tires or something, just to stay away & let things evaporate. Maybe turn the muffler down and wiggle the prop so the piston is at the bottom, let anything in the combustion chamber drain out & get fresh air.

Later I start with an empty combustion chamber and fresh air & prime the engine, just a squirt of fuel in the carburetor throat and a few flips of the prop.

At that point, I hook up my glow connector to my adjustable power panel (rather than use a hotshot.) I adjust the current by the meter, up to the top of the green line, and turn the prop in the direction of rotation until I feel some compression, and stop. I let the glow plug heat things up for a while (20 seconds minimum) and flip the prop in the WRONG direction, with a stick. It should pop.

If it didn't pop or start, I DON't hit it with the starter (yet.) I'll disconnect the glow connector, prime again, and turn the prop OPPOSITE the rotation direction, until I feel compression, and stop there while I hook up the glow driver. Wait 20 seconds while it warms things up, and spin with the starter motor. Should pop and run on what fuel is in the crankcase, for a few seconds, regardless of how bad I've botched the needle adjustments. At that point, if it doesn't start, I begin to suspect the fuel. If it starts & dies, I've botched the needles, and start a methodical adjustment.

Anyway, that's my take on it. Don't know if it'll help in this case, 'cause you may have a scuffed piston or something causing extra friction. I fought one of those for, well, too long, and finally took it apart, that's what I found.

Good luck,
Dave Olson

RE: thunder tiger GP .07 problem
 

I have the same problem too. I've tried everything, except using an electric starter since I don't have one. The closest I got it to start was that it sputtered for about 2-3 seconds. thats the most life I've gotten out of it so far. Glow plug is fine, and the engine is nice and tight. Today me and a friend are going to try out his electric starter and see if this thing runs. I'll keep you posted after today.

RE: thunder tiger GP .07 problem
 

My memory is getting jarred again. I tried to use the standard size fuel line with a filter, didn't work very well. I switched to the small line without filter. The only prop that worked for me was the MA6x3. 6x4 too big, apc's 6x3, 6x4 to much load on engine. This was using 30%.

RE: thunder tiger GP .07 problem
 

Some engines are very tight at TDC when new, how tight is your engine at TDC?, if it is really tight you may want to heat the head up with a heat gun to help loosen up the engine til you get it broke in. My .07 is still in the box, i hope i don't have as many problems as you are.

RE: thunder tiger GP .07 problem
 

Hmmmm.... this thing is proving stubborn.

Before you put it back in the box and then kick the *ell out of it........ tempting isn't it ?

Try just putting a couple of small drops of fuel down the carb with the tank disconnected.
Give it a spin on the starter. If it doesn't start try another couple of small drops of fuel and spin it again, if it still doesn't run then give it one more try.

If it doesn't run for a short burst during this process then it is not looking good.

Someone else has posted a good way of doing this.

The only other thing I can suggest, if you haven't already done it, is to try another plug. It might be glowing when out of the cylinder but not performing correctly in the engine.

I never had this amount of trouble (fortunately) I just couldn't get the thing to start by hand when new.

If it does run by means of just priming into the venturi then it may be worth while inspecting the very thin fuel line which comes with this engine. I use normal fuel line from tank to filter and then managed to get the thin stuff onto the filter and then the carb connection. I also use `normal' fuel tube from the pressure nipple on the muffler back to the tank. That thin stuff would be easy to damage and also kinks very easily.

Reg

RE: thunder tiger GP .07 problem
 

Hi
5-15% nitro is all you need.
are you sure you spin the prop counter clockwise!? And that you have opened the highspeed needle enough?? (2-3 turns ).

When you turn the prop by hand, holding a finger over the carb intake, you should see fuel comming in the fuel line too the carb. Can you see this?
How does your glow starter work?
You should have a 12V, 10A Motorcycle battery and an automatic glowdriver!
Holding the glowplug in your hand it should lit with a bright yellow/white/orange glow...not dull red!
Those small 1,2V Nicad one-cell devises are not that good!

RE: thunder tiger GP .07 problem
 

yep yep yep to all you questions
1 i use a hobbico glow starter for my hobbico power panel
2 yes the color is a orange/white/yellow
3 fuel is 15% hobbico 1/2a fuel
4 i use a 12 volt rider battery
next step i am going to take this engine apart to see whats wrong
if i find no scratches in the cylinder wall should be none because it is a new engine and i have had the head off to see before.
if i find nothing wrong i will send it to thunder tiger/ace hobby and tell them what is going on and see what they say.
you know this is a cool and very small engine i never know it was going to be a real Pain the the flaps,,,,......... if i would have known that i would have bought a AP wasp


thanks for your help.

RE: thunder tiger GP .07 problem
 

Mine starts relatively fine by hand but it only starts at idle (took me some time to figure that out). Needle valve was at about 2 turns from factory (recommended is 2- 2 1/2), I need about 3 turns to get it started and then it runs fine at about 2 1/2 turns (still running in). Fuel is what I had at home: 16% nitro, 20% castor. Only tried with Enya #3 plug so far.

It runs and throttles fine for such a small engine but one anoying thing is the sloppy crank case that tends to rattle at intermediate revs (using a balanced prop and original prop nut).

I haven't tested the high end properly yet, but reports here seems to be that it is not especially impressive...
Has anyone tried with a Nelson or Turbo plug? Or maybe a Merlin plug could do the trick without modification?

RE: thunder tiger GP .07 problem
 

The alternative plugs you mention have a different thread diameter and pitch. They are not 1/4-32

RE: thunder tiger GP .07 problem
 

Yes the Nelson and Turbo plugs are different and will need a custom made head, but the head has a flat disc that could fairly easy be copied (some people seem quite skilled on this forum...) to take a different plug and thereby avoid the influence of the volume in the plug-threads on the combustion?

The Merlin plugs I assumed were standard threads?
They have plugs labeled 1/2a that they claim will add 1000 rpm...