Pulsing sound from 600LE

[vartegrich]

Hi, have you had a look at the torque tube ?????

I just wondered if the center bearing has moved or worn out ??????

any chance of a video ??? That would help
x Rachel

I'll see if I can get some video of it tommorrow.

[vartegrich]

Is the tail spinning freely?
Coz went i brough my 600le up the field we had to take the boom of for transport! And wen we put the boom on we didnt realise but we pushed the boom in so hard tht the bevel gear (in the plasteic boom gearbox mount) got forced out of its bearings by bout 1mm wedging it into the other bevel gear which caused the tail to be a bit notchy and it made a hell of a racket wen it was spooling up!!!

Its worth a check coz its hard to notice!!

Everything is nice and free with no notchiness.

[paul35]

Have you checked all the teeth on the tail drive? sounds like the tail is losing drive

[vartegrich]

I'll pop the front gearbox off tomorrow and check but they were replaced less than 20 flights ago.

[Nick B]

I know you said you think its not the engine but it may be worth popping the backplate off the engine and looks for rust on the rear bearing

[vartegrich]

I did wonder about bearings not because of this problem, but moreso because the engine is notably louder and a little lazier starting.

[Nick B]

Get it checked dude,4 bolts and you will know

[vartegrich]

Will do.
I'll post back tomorrow with some findings (hopefully)

[vartegrich]

Quick update.

A quick check of the Trex gearing shows no missing teeth and the amount of slop seems to be consistent between the main and tail bevels.

I've now pulled the engine out of the airframe.
With the crankcase cover removed, there is some staining on the crank and rear bearing. See the attachment.

The engine had its initial 10 flights on ProSynth 10% and now has had over 5 litres of Optifuel 20%. I had a blown piston on its 10th flight and hence the switch to the Optifuel. Since then it has always run with the crankcase cover cool to the touch.

Does the photo indicate a bad bearing? There is a slight roughness if you swing the fan from compression to compression but only slight.

[paul35]

I can't see that giving you any problems, if you spin the head up by hand can you hear any strange noises

[vartegrich]

Nothing out of the ordinary. Time to put it back together, go flying and see if the noise is still there.

[StreetDragster]

I have had similar strange noises on my 600LE, as has my friend with his 600NSP.

We have had failed bearings in the main shaft and clutch stack, and engine bearings all cause odd noises with associated tail movement, maybe worth giving them all a check over, Align bearings are pants in my experiance.

Thanks

Matt

[CChris]

Since then it has always run with the crankcase cover cool to the touch.

I had bearing problems until I stopped running my engines cool. In my option running an engine too cool or too hot is bad, you need some heat.

I had problems determining what was too cool or too hot, until I purchased a little onboard head thermometer, which recorded the high point during the fligh (used by the RC Car guys, and cost around £10) much like the new telemorty stuff from spectrum. I found my hyper 50 would not exceed 50 degrees C which I upped to around 75-80, since then no bearing problems.

Hope you sort it soon

Chris.

[vartegrich]

I had bearing problems until I stopped running my engines cool. In my option running an engine too cool or too hot is bad, you need some heat.

I had problems determining what was too cool or too hot, until I purchased a little onboard head thermometer, which recorded the high point during the fligh (used by the RC Car guys, and cost around £10) much like the new telemorty stuff from spectrum. I found my hyper 50 would not exceed 50 degrees C which I upped to around 75-80, since then no bearing problems.

Hope you sort it soon

Chris.

After popping the piston after going lean then prevention was a safer option. Mind you, I am only just 1.25 out on the main needle at the moment.
Well it looks like there is plenty to think a out today.
Time to go flying.

[Nick B]

If theres rust on the crank there will be rust inside on the bearings,unfortunatley cant see for the webbing

I would strip the engine personally and fit a new rear