Trex 600 Engine Alignment

[Gate88]

So I changed the rear bearing in my os55 for about the 10th time this year, all quite straight forward til i put it all back together again. Once it was all done I span the main gear with my thumb and the autoration seemed rather tight compared to how it was before I started.

I thought maybe the clutch and engine werent aligned properly so I loosened the engine and the clutch bearing block and everything was normal (ie the main gear span freely) until I tightened it all up again.

I stripped the whole thing down, made sure none of the bolts were bent and that none of the holes had any debris in them but all were ok. I replaced the bearings in the clutch block, cleaned out the teeth of all the cogs, re-assembled everything and its all fine until you finally do the last few turns tightening up the last of the bolts. At that point the main gear to clutch tightens up.

Another complete strip down and re assembly and it the same story, the autoration bearing is only a couple of months old and spins freely off the model so I dont think its that. If I take a turn out on each of the engine mounting bolts, its all good, and like wise a turn out on the clutch bearing bolts it all spins smoothly.

Anyone ever had this or got any suggestions as to what I can do about it cause its driving me mad.

[waveydavey]

Make sure the bottom Jesus bolt isn't too tight Guy it deforms the one way. Have you really changed the rear bearing 10 times, chuffin Norah if you have, I've just put a 55 in my 600.

[Mike W]

when you putting the engine in do you sit it loose with the bolts in and spin the starter to let it find its own centre then do the bolts up ?? .... oh and how tight is it ?

[Gate88]

Make sure the bottom Jesus bolt isn't too tight Guy it deforms the one way. Have you really changed the rear bearing 10 times, chuffin Norah if you have, I've just put a 55 in my 600.

Yea I tried it without the nut on the back. I'm just wondering if the frame has somehow warped.

But the thing to remember about my 55 is that I tend to change my bearings whenever I have an hour or so free, I do it whether they need them or not just to save me having to do them once they get noisy & I havent got time. Its also a damn sight easier to clean inside the frames once the engines out!!!

[tonystevens]

have you tughtened the propnut fully so that the fan mount has bottomed out on the crankshaft washer.A guy at our club had the same problem and it turned out to be that.The clutch was sitting too high and binding on the clutch bell.

[Gate88]

when you putting the engine in do you sit it loose with the bolts in and spin the starter to let it find its own centre then do the bolts up ?? .... oh and how tight is it ?

Now that's a good idea! I haven't tried that but I will later.
It's tight enough that if I give the main gear a spin with my thumb it will only continue for about half a revolution with the inertia. Whereas it always spun almost two revolutions before.

[Gate88]

Probably going to get flamed for this but I went with Mike W's suggestion, well a bit further actually. I spooled it up with the engine and clutch block slightly loose and then tightened it up and its back to normal now!

[spunkmyer]

Guy this is what happened to my Raptor as you know. Had to centre everything just as Mike W suggested and then it was fine. Still spins the blades a little at idle though which it did not do before. Glade you got it sorted. You going down the club this Sunday?

[brin]

when you putting the engine in do you sit it loose with the bolts in and spin the starter to let it find its own centre then do the bolts up ?? .... oh and how tight is it ?

great tip mike .i have had the same problem but with the raptor.