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jakesvdm
05-09-2008, 12:45 PM
Hi, I have a Thunder Tiger 39 Pro engine in my Raptor 30 V2. It's got no more that 8 liters of fuel through it. Cool Power Low Viscosity Fuel (15%).

The strangest thing has happened. Someone at the field tuned this engine and I was really happy with the power I got. Climb outs was real nice, etc. The I decided to get rid of the CSM 180 and replace it with a GY401 and S9254 servo. So next weekend at the field, while spooling up the heli, round about mid stick, the engine sounded like it was about to die. Throttle down, and all is fine. Next thing the tail broke. So I took it home to fix, and next weekend the same problem. Round about mid stick while spooling up the heli sound like the engine wants to quit. Throttle down and all is fine. I replaced fuel line at the field, glow plugs, but no success. Again I went home, stripped the carb, didn't see anything wrong, re-assembled it and whoala, all seems fine again (didn't fly it, but at home, it went past the half throttle mark without quitting). Next weekend at the field, the heli spooled up, who knows what was wrong.

But now I noticed that it hasn't got any power. I didn't take out the idle screw (one at the throttle linkage end), and I counted the amount of turns the high en needle (one at the fuel line end - with the ratchet) was turned out, and I left everything the same when I reassembled the carb. What could be wrong ? Just all of the sudden power loss ? The engine bogs, climb outs are pathetic. This heli is just not the same.

Settings I have on the carb :
Not sure about the idle needle (or low end needle)
The other one (high end needle - one with the clicks) is 3 and 3/4 turns out. Factory setting is 3 turns out. I must add that we are about 1600 meters above sea level. The guy who tuned this engine had it there and it was really fine. Lots of power (to me at least). But know all of the sudden - Nothing.

Please help. What could be wrong. I'm also struggling with the standard TT exhaust. The bolt / screw that goes through the middle keeps on coming loose. This exhaust is a 3 piece exhaust. Now I used some gasket maker on the exhaust to create a seal. It can withstand 300 degrees C. Could this be the problem ? Maybe choking the heli ?

vandelescrow
05-11-2008, 10:28 AM
The only thing I can think of is your getting dirt in your fuel. I have a filter on the line that goes from the muffler to the tank just in case, and I recently found the filters I had on my main fuel line and the fuel jug did not filter adequatly. The holes in the screen were too big. I now have the "dynamite" filters. http://www.ronlund.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=heli&Product_Code=DYN2006.

To clean any dirt that may be in the needle, you do not need to remove the carb. Remove the needle like you did (turning it in counting the clicks, then remove it) pump some fuel through the carb, and reasemble. I was told a particle so small you can not see, can cause the needle to be out of adjustment.

About your muffler, In a different thread here today someone posted how he fixed the bolts on the 3 piece muffler from coming loose.

jakesvdm
05-22-2008, 12:47 AM
Thanks for the help and advice. I crashed my heli and I'm going to upgrade to a 50 now. I will replace the fuel filter too.