Starter shaft binding up

[ntwaddell]

So after breaking in my helicopter yesterday, i tightened up the gearlash a bit. I went to start it today and the starter shaft binded up. So I dropped the motor, it spins freely. the motor spins freely. I have tried adjusting the alignment between the engine and the upper clutch area and no go. When i push the engine up, it feels like it is too tight. Like something expanded, i have to push it pretty hard just to get the holes to line up. I took the upper shaft apart and everything is together, not bent. Any recommendations? BTW it is a Raptor 60 v2

[LAMAR COOLEY]

ntwaddell,

First. In adjusting the lash. It's necessary to maintain a perpendicular alignment
to the motor shaft as well as perpindicular alignment of gear and penion. You
may have to elongate the bearing mounting holes slightly
to achieve this. That done.
Second. The motor shaft needs to be perpindicular to the starter shaft.
You may have to elongate the motor mount to frame holes to achieve this.
Third. Depending on the motor used. Shims may be needed at motor to motor
mount. If I remember right these shims are needed if using a Thunder Tiger
engine. But not required if using an O.S. engine.
Here again not knowing what size engine you a useing.
Hope this may be of some help.
" Keep the right side up or down. Depending on your grey cell viscosity ".
Regards :D

[ntwaddell]

So while I was at the lake, the answer came to me. What happened was the bolt that holds on the fan came loose and the fan unthreaded about a 1/4". So the motor assembly was too tall and mashing into the clutch housing. All fixed and loc-tited. A crank shaft stopper thing would have came in handy though, what do you guys recommend for .70 size motors.

PS. the motor is a Thunder Tiger .70

[chris696]

take the carb off and push a toothbrush into the port to lock the crank. works everytime. but make sure there is no debris in there before you re assemble. regards chris

[BarracudaHockey]

Or do it right and get an OS cranklock tool.

[ntwaddell]

Will an OS tool work on a TT engine? I will have to see if the hobby store has one.

[ntwaddell]

how tight should the gear lash be?

[LAMAR COOLEY]

ntwaddell,
The most common way is to use a strip of paper ( width = main gear or
slightly wider x length = 6" to 9" long )
Feed it into the gears. 1.)notice the crispness of the folds= not too sharp
and not too round edges. 3.) paper should slide out-up while inmeshed.
Beaware that some main gears may be slightly out of round. So you may have
some tight spots. Set the mesh to the tight spot.
I haven't experienced this out of roundness with my Rap.90 or Rap 50.
But have seen it several times with my Trex 450. :oops:
Hope this may be of some help.
And I'm sure there may be other methods
Regards :D

[ntwaddell]

thanks! what about if you hold the clutch bell and move the gear with your finger? how much play should there be? I will try the paper trick when I get home.

[LAMAR COOLEY]

Once you set the gear lash with the paper strip. :wink:
The lash tolerance would be that thickness.
So there will be very ,very little to none.
Holding the bell and trying to move the main gear is how you would test anyway.
Regards :)

[Fade-Dude]

Dudes!!!!!!!!!! I have/had the same problem.... Thought it was mis alignment, but after reading this post, took the engin out... checked the fan... well what do ya know! Also was turned out and the egnine didn';t really fit in nicely...

I turned the fan all teh way in until it could not go anymore? That right?

Also, what is the ebst way to keep it in place? I lock tighted the grub screws on the sides, and also locktighted the nut that screws in from the top and fastened it with a socket as tight as I can?

Is all that right?

Thanks for the help!

[LAMAR COOLEY]

Fade-Dude,
The fan will sometimes back-off the shaft when you get a kick-back while starting
or the motor runs the wrong way.
As the fan wants to screw on as the motor is running in the right direction.
Also if your are using a shaft washer on the shaft and then installing fan it makes the fan stand off some. Do not use the washer. I do not recommend using anything to block the shaft through the carberator opening while installing the fan. As this may cause damage to the shaft port. (Some folks use a wood dowel or tooth brush handle). If at all possible use a crank shaft tool to hold the shaft at the piston. Requires removing the back plate. Then tighten the fan while useing a rag or cloth over the fan to get as tight as you can by hand.( There are other techniques for doing this tightening).
Use locktite on the fan threads. Use locktite on the shaft nut. Grubs screws ? :?:
If you mean the screws that hold the clutch? Use locktite. I am not aware of any screws that would grub the shaft. :dontknow As these would damage or mar the shaft and or
threads. Mike Prewit has a fantastic web site called "Raptortechnique". :noteworthy
Check it out. I would post a link to it. But don't know how to do it yet. :dontknow :oops:
I hope this may be of some help.
Regards :D

[ferincr]

http://www.raptortechnique.com/
There you go

[Fade-Dude]

Than ks guys, I've read alot on raptor technique, tho not all of it :-)

The fan has got two big ass grub screws on the sides. :dontknow

[ferincr]

I think (if I'm not wrong) those are holding the plastic fan to the aluminum center piece that screws to the engine shaft and where the clutch is screwed in.