Maiden 600N engine start - cracking sound and broken frame?!

[yarbsea]

Okay, first off, I eventually fixed this problem and the heli flew later that day...HOWEVER, here is my story.

I had everything put together for the initial engine starting. I tried the starter wand and it was very very tight to spin the engine, but the OS manual mentioned it might be pretty stiff with the new engine.Well, I kept trying to start it and it was taking some sserious torque....until I heard some cracking sounds...turns out the frame cracked on both sides where the fuel tubing goes through the frame to the muffler fitting.

Well, I dropped the motor and pulled it all apart and put it all back together and it was nice and smooth again...eventually the whole thing worked like a charm after I re-installed it.

So - big question is...anyone have any idea what could have caused the motor to not turn?

[Bobbyk]

It may be Hydro lock, were to much fuel enter the combustion chamber and makes the engine hard to turn, one of trick is to tip the heli on the muffler side to empty the fuel. Some others take out the glow plug and empty the fuel but thats a long winded way.

Also only take fuel clip at the last minute when you start the engine.

Hope this helps.

Robert

[LJS]

Hi Yarb,

As Bobby says, it could have been hydro-lock. If I leave my throttle barrel open even a slight amount, fuel drains into my engine while it sits. The solution is to kill your engine with low throttle trim, and then leave the barrel fully closed until you're ready to start your engine. Doing this, I never have any problems and it always starts right up.

Keep 'em flying.:YeaBaby:
LJS

[wrex]

Sounds to me like your engine was installed a lil crooked. if your cluth bell does not sping free with your fingers then you have an alignment problem. when you removed the motor and reinstalled it, you may have torqued all the bolts evenly to fix the problem. or something to that matter.

[erniefritz]

you hydro-locked it..... the way the trex is put together , it is almost impossible to get the engine clutch alignment so out of wack that it will lock up the motor.... Tried it last night while i was replacing the clutch bell in mine , even at it's worst the engine still turned over...