Main gear UP/Down Play

[Stevin]

My friend just built this heli and I personally love the looks of it and the way it flies, very solid in the air and just feels like cheating at times! We noticed some cushion play on parts like the tail blade grips can be pulled apart but supposedly the manual mentions this is designed this way. I also noticed that the main gear has some considerable play up and down but the manual does not mention this. Does everyone have this play and should it be there? If not how did you remove the play in yours?

[aseejr]

My heli has about a 1mm vertical play on main gear, main shaft does not move.

I have asked before about the tail grips. The play is by design.

[Phil777]

Both my machines have no play up and down on the main gear.


Check the head is not moving up and down when u hold the frame and lift the head.

If it is loosen the 4 screws holding the upper bearing block. And loosen the 2 holding the bottom gear.

Push the bearing block downwards evenly and re tighten. Same with the bottom gear.

If you don't get rid of that play it will get worse and you will need to replace the bottom gear.


Remember to re loctite

Sent from my GT-I9300T using Tapatalk 2

[Adam Landefeld]

Couple things...

As mentioned, do loosen the bearing blocks and push the top one down (toward the main gear) while you tighten it back up and push the bottom one (toward the main gear) up as you tighten it back up.

Also, make sure both bearing blocks are in the right way (flipped to the correct side)... make sure they are positioned to where if you were to press the bearing out of them you would have to press towards the main gear from each block (saw this one before, resulted in a couple mm play).

In an inverted crash it is very possible (i've done it twice) to "dish" the bearing block on the bottom block. It will bend with a slight bow in it and create that extra spacing. It should be perfectly flat, check it with a straight edge if you suspect it.

Let us know what you find.

-Adam

[aseejr]

First I checked my main shaft / head. 0 play. But there is that 1mm vertical play between the main gear and the tail drive pulley.

I took the head off...checked if I assembled head - main shaft - main gear - tail drive gear. Everything seems to be according to manual. Reassembled everything keeping in mind to push the upper block down. Result still 0 play on head and main shaft....BUT main gear still has about 1mm vertical play away from the tail drive gear. Checked the Jesus bolt.....it's on correctly.

If there isn't supposed to be this play between the main gear (1-1) and tail drive pulley(1-2) I think the solution is to place a washer between the c-clip (1-4) and one way clutch housing (1-6) or elongate the Jesus bolt hole on the tail drive pulley (1-2).

[Adam Landefeld]

There is a little up and down play of the main shaft on the auto hub, it is normal on both my e720 and my G4 Nitro. I thought you were talking about the whole head up and down. Yes, don't worry if the main gear can move up and down a mm or so on the auto hub (one way housing). You don't need to put a spacer near the snap clip.

-Adam

Originally Posted by aseejr

First I checked my main shaft / head. 0 play. But there is that 1mm vertical play between the main gear and the tail drive pulley.

I took the head off...checked if I assembled head - main shaft - main gear - tail drive gear. Everything seems to be according to manual. Reassembled everything keeping in mind to push the upper block down. Result still 0 play on head and main shaft....BUT main gear still has about 1mm vertical play away from the tail drive gear. Checked the Jesus bolt.....it's on correctly.

If there isn't supposed to be this play between the main gear (1-1) and tail drive pulley(1-2) I think the solution is to place a washer between the c-clip (1-4) and one way clutch housing (1-6) or elongate the Jesus bolt hole on the tail drive pulley (1-2).

[Stevin]

Yes the play I am referring to is betwee the main gear and c-clip

[Adam Landefeld]

Perfectly normal on all the G4s I own and the others at the field my friend.

-Adam

[Don S]

You could add shims if you aren't happy with it. I've done it with my 50, and it seemed to eliminate some "noise" from the heli.

[borntofly]

The play is supposed to be there. Don't shim it. It's designed that way to allow movement during operation, you want it to be able to move a little when the gear heats up. It will find its sweet spot during flight and won't move.