one bearing jamming up?

[choppaholic]

hi all,

the on way bearing on my 600 keeps jamming up, i bought it second hand and the previous owner had the same problem. when i got it i replaced the central hub, one way bearing the whole main gear assembly. this only seems to happen if left idle for a week or so. the whole main gear assembly is well greased.

Any idea why this happening, the previous owner had this twice and now me so its 3 times now. it frees up if you disassemble the main gear and shaft. this is what has been happening previously as well. it doesn't seem like a bearing issue since three different bearings cant jam up can they?

the main shaft is straight. what else can it be

any ideas please.

thanks guys

[sacko]

There is a kit, I bought it for mine

Changes the bearing, hub and sleeve..

EDIT: and dont overtighten the jesus bolt

[Jamin_00]

I know stating the obvious but are you actually greasing the one way itself with plenty of grease.

[Steve]

The grease might be the problem - there is much debate on various forums about whether or not you should grease a main-shaft one-way bearing at all. Some say yes, some say no.

Grease is great when it's clean, but is a magnet for dirty particles, which could then in turn cause problems like you are describing.

Personally, I've never greased one, and never had a problem with one in 8 years and many helis, apart from one Hirobo one which split its casing, and these particular ones are known for this failure.

It's just a thought...

[choppaholic]

There is a kit, I bought it for mine

Changes the bearing, hub and sleeve..

i didn't understand, please explain, i have changed the sleeve, bearing hub already.

Ben,

the one way is well greased. i have even greased the whole main shaft and sleeve, just to be sure .

[Jamin_00]

I only grease inside the bearing not the shaft, I rely on the oily mess from the fuel keeping everything else nice and lubed which I clean after everyday flying.

I replaced my one way on my Aurora and forgot to grease the one way and it squealed like a pig.

[waveydavey]

Just an opposing view. Most of the guys in the club don't grease and have theirs lock up and I grease and it has never locked up.

[Jamin_00]

bring it sunday and we have a look, something is obviously not right.

Maybe something is out of line somewhere.

[choppaholic]

bring it sunday and we have a look, something is obviously not right.

Maybe something is out of line somewhere.

thanks Ben, if i dont crash it by then i will bring it .

the new bearing, and hub that i bought as replacement came with lot of white grease on it. so if grease could be a problem why is i there and if it is, how do i get rid of it?

[moyesboy]

I found a crack in my one way sleeve. Caused by overtightening the jesus bolt. This hadn't caused a problem with locking up, I found it when changing the main gear - I bet it would have had it grown a little lnger (from the bottom edge it had grown past the hole and beyond...)

[J-S-Q]

Sav I'm pretty stumped as to what's causing this... so it has a new main shaft, one way bearing, sleeve AND hub?

Guys... I sold this heli to Sav. I never had a problem with it and then in the last couple of weeks that I owned it the one way locked up twice in quick succession. I can't think of anything that triggered this problem -no crash or hard landing etc.

I think the grease issue is possibly a red herring -there must be something else going on. Is it possible that the inside of the plastic gear has become warn causing one to over tighten it thus distorting the bearing sleeve a fraction? Could the main bearing blocks or the clutch blocks be slightly warn, allowing things to be fractionally misaligned? -I'm not sure how feasible either of these are (particularly as I never flew it that hard, just sport flying) but they're just random guesses?

One thing that has just occurred to me whilst typing this... you know the engine fan mount, this part here:

Fast Lad Performance

-it did take a bit of a bruising once when I had a very hard time removing it from the engine (ended up having to buy a pinion puller to get it off). I'm wondering if it's become slightly bent which could cause some uneven forces between the pinion and main gear -does anyone think this could have something to do with it? I'd be happy to Paypal over the cost to replace this part and see if it does any good although I must admit it's a bit of a wild shot in the dark.

Oh and just for the record guys, I did tell Sav about this unexplained bearing lock up issue before he bought the heli! Hope it can be solved soon.

[choppaholic]

Thanks Jamie, i have freed it for now and 2 tanks later it seems ok, will keep an eye on it and see what happens, it might just be the jesus bolt as suggested by Sacko since i like my bolts tight and by the rebuild i did you like it tight too , so i have loosened it and lets see what happen.

thanks all

[choppaholic]

its jammed up again, so it not the Jesus bolt...

i cant think of anything else an more ideas guys

[choppaholic]

if it helps anyone,

I finally figures out what was causing the oneway bearing to stick. Its the main gear and auto rotation gear. They look ok but do not run true and might be sending some uneven force into the bearing locking it up (cant tell by looking but new once have not locked up after 6 flights old ones locked up on the first flight every time). After replacing many parts, it was simply the main gears but was this one a pain find. I actually bought a brand new 600 Sport and replaced everything between the engine and the main shaft including the main shaft.

Many at the club said why don’t you put the electrics and engine on to the new on and be done with it. Where's the fun in that plus then i will have only one 600 then!!

When the problem disappeared I replaced slowly one after the other the old parts until it started to seize again. Would have been a lot easier if I replaced the main gear first but all good now. happy

[J-S-Q]

Really glad to hear it's finally solved. shame it's been such a load of grief though.