View Full Version : Glitchy 90SE....
Well after 50 straight beautiful trouble free flights and no changes I now have a glitch issue. The past 5 flights I get tail or cyclic locks for a second or 2. I am running a 72 mhz radio system. It has S9252's on the cyclic and 611/S9256 on the tail. As I stated no changes but now suddenly a glitch every 2 minutes per flight. Scarey stuff. I have checked ALL bolts..they are still tight. I assume antenna routing/servo wire routing and placement is OK since it sure worked for the first 50 flights. All pins are tight in gears and look like they are in their original positions. I have never done a "run out" on the fan but as I have stated it sure worked fine for the first 50 flights.
I do feel the jetting is OK. I vary it with the weather. It is now winter here but I don't have excessive vibration ever with the Heli.
Got any ideas for this Nitro Rookie??
My idea is new main bearings and ????
Can the motor alignment with the clutch bell be an issue. I have always lined it up by eye but there seems to be a 1/16" variation I can make with the motor placement and it always seems lined up.
All on the Heli were brand new when I got it.
Any help is appreciated.
Eric
Laurens
02-01-2008, 06:06 AM
I think one of the bearings is broken by now. Try all bearing by hand if they feel notchy.
Kinger
02-01-2008, 07:30 AM
Look for notchy bearings. Also make sure the bolts that hold your boom supports to the metal boom support bracket on the tail. (Over time these can become loose and cause RF noise with vibration.) Are you using the metal center pin on the headblock or are you using the infinavation dampner head pin which is a composite material?
vandelescrow
02-01-2008, 09:00 PM
Are you using PPM or PCM on the transmitter / receiver? I had the same problem on PPM, switching to PCM got rid of it.
Ok guys thanks for the help.
I am running PCM on the radio, don't have any loose boom support bracket bolts and both the main shaft bearings feel smooth but my oneway bearing for the gears was stuck!! I have taken it apart and it is moist with grease but was definitely stuck. I had to tap on the oneway shaft with a hammer because it wouldn't budge. It popped loose and the one way is now working. I took the one way shaft out and it looks fine as well as the main shaft....I think I will regrease it and give it a try. I bet that was the issue. I think I will order a UK one way clutch assuming the bearing is better quality or am I wrong? Should I take apart the one way and lube it more ofter than 50 flights?? Sorry if that is a dumb question but I am a rookie when it comes to BIG NITROS. I put over 2000 flights in on my Trex 450 SE last season and know how to maintain those but this larger heli stuff is new to me.
Oh and by the way I put those 50 Nitro flights in a 3 month period so that oneway bearing hasn't sat much between flights.
Thanks for all your input. It is very helpful.
Eric
Laurens
02-02-2008, 06:34 PM
I've had my oneway getting stuck too. I greased it while assembling, and thats something I SHOULDN'T have done. This way the pin rollers will get stuck faster.
I bought the quickuk oneway, and haven't had a single problem since. It even feels smoother then the stock oneway.
ColinB
02-02-2008, 06:40 PM
If you put your foot over the skid tubes of the heli (to hold it on the ground) and firmly pull/push up/down on the rotor head does the main shaft move at all? Any up/down play between the main shaft collar and the top bearing can cause lock-outs. This and loose boom supports is normally what causes it for me.
Colin
Colin...I currently have it apart so I can't answer your question. I believe that I had no play but since it is apart I don't know.
Laurens or Colin or whoever...should I not use grease on the oneway?? I always have on my Trex with success but obviously not this heli...I will use tri-flow if grease is not good.
Thanks.
Raven_darkcloud
02-04-2008, 02:34 AM
Ya, grease and one way bearings dont work as the pins need to move for grabing the shaft and then letting it spin. The grease picks up dirt and gets a little gummy witch stops the one way. I do use tri flow on alot of places but I have not used it on a new oneway. Only after a teardown with cleaning. My first raptor is on its way so I cant say for tt, but all my rex one ways have ben oiled when I pull them out of the package. One the x400 they came dry and I added triflow.