Is it time for a engine rebuild>>>>please help!

[TCU 02xp]

I have been flying a hyper 50 with a revolution muffler for a little over a year. I have probably gone through 16-18 gallons during that time. After one of my last mishaps i noticed that my magnet came out of my fan for my Curtis governor.

I reinstalled everything, changed all fuel lines, including the tank, and removed the carb and throughly cleaned. Here is my problem, it idles fine, I have the governor set at 1800, ill get it in a hover and after about 10-15 seconds the engines starts to rev and the rpms get so high that the blades start to flutter. I have tried a new glow plug and no change. Its not running too lean, its has plenty of smoke.

My question is do i just have too much time on this engine and it was coincidence that after a crash the engine is now worn? You're help and previous experiences are grealtly appreciated. Thanks!

[Seeker]

Turn your gov off and see what happens to the RPM. It could be the gov is not working right.

[BarracudaHockey]

Did you seat the carb fully when you put it back together?

[TCU 02xp]

Well i just found out my main shaft has a very slight bend in it, i had to look at it many times just to double check. I replaced the feathering spindle yesterday. Would a slightly bent main shaft cause it to pick up rpm at a higher throttle and make the blades flutter?

[flyinfool]

I doubt that a bent main would cause a change in RPM, but it will cause blade flutter.

[BarracudaHockey]

Looking at a shaft isn't going to tell you a lot. If in question, roll it on a piece of glass, if it taps its bent.

The spindle can be checked quickly on the heli by removing one blade and turning the spindle with a hex driver, if the opposite blade tip wobbles up and down its bent.

[TCU 02xp]

i should have specified, i took the main mast out and rolled it on a piece of glass. Just a slight bend, nothing like after a crash, probably came from a hard auto. I know about the trick with the spindle, everything is good there.

[Seeker]

So have you tried it with the gov off?

I'm curious to know if the problem is in the gov or in the engine.

[Rodan]

A friend had this problem recently, and it was too lean. Don't go by the smoke....

[TCU 02xp]

I totally disconnected the gov and that was not the problem. I didn't just flip the gear switch to turn it off, i disconnected it. I know its running plenty rich because its a little sluggish before it starts running like a raped ape!

[Rodan]

The problem my friend had did not present until the motor had warmed up (this was in Feb), and with the warmer weather you might be seeing the same thing.

If it's sluggish coming up "on the pipe", the low end may be a bit rich, although it could still be lean on top.

This problem frustrated us for a while before we figured it out...

[comeflywithme]

Have you checked the engine temperature?. Thats normally a good way to tell if you're running too lean. I recently had a simillar problem and found it was due to a small piece of fluff in the header tank fuel line - god knows how it got in there!!

Are you sure its not something as simple as your throttle control having got moved during your mishap - although if that was the case your heli would start up faster than normal too.

[TCU 02xp]

Well i replaced the ring today and had the owner of my hobby shop look at the engine. Still no luck, i am so frustrated i feel like selling the damn thing. The engine is running around 190 degrees so i know its no over heating. The only thing left to do is replace the engine i guess????

[TCU 02xp]

PROBLEM SOLVED!!!

I cannot believe i spent all this time and the problem was the blades. I was at my local field yesterday and had a guy look at my machine that use to work with Curtis down in Hearne, Texas. He said take the blades off your 600 trex just to see if the T. TIger blades are your problem. Sure enough i put the radix on my nitor and problem solved. The wierdest thing is after i moved the T. Tiger from my nitro to my trex they were fine, no fluttering no nothing. Thanks for y'all help though!