Hi there, please mail me with any Predator questions. I have some experience with this type...I have been flying mine for about 18 months now.
The manual is crap, it shows the build ok but the finer points its a bit lacking...unless its changed.
The most crucial point is about the tail gears...the book shows these shims that are installed on the output shaft...its misleading because the bearings can get overloaded.
The trick is to assemble the gearbox halves...just hold them together...and take the output shaft and see if it has some end play...if so then thats fine....if not the bearings will get ruined.
Century bearings are rubbish, try Boca Bearings...they sell bearing kits for quite a few helis including the Predator.
The other concern is the Mainshaft end float...the bottom bearing is a plain ball bearing..it does last a while...I have just changed mine. Make sure to add a shim if needed...you dont want any floating as the main shaft can rise and close the meshing of the tail drive take off cog...this cog needs backlash so closing the distance will ruin things...I didnt have a failure as such but with the pressure the tail drive cog will bear up causing its front bearing to overload...mine jammed and started to wear the shaft end..I used solder and some 'machining' to build it back up...didnt have the parts
Worked a charm.
Also be careful of the tail drive shaft key way...it needs to go back further...I used a file to adjust this...where the cog sits is too close to the main shaft...so the backlash is almost non existent.
Please e mail me on:
robwilkinson@horizon.co.fk this will be better as I can send pics of the parts etc.
Rob