RunRyder RC
 3  Topic Subscribe
WATCH
 2 pages [ <<    <    ( 1 )     2     NEXT    >> ] 1487 views POST REPLY
Scorpion Power Scorpion Power
HelicopterHIROBOOther › x-spec growing pains
12-20-2003 05:59 PM  13 years agoPost 1
elviswl

rrApprentice

Fort Lauderdale, South Florida

My Posts: All  Forum  Topic

x-spec with ys 91

I heard metal to metal sounds when starting, but the sound went away once the engine fired up.

After thrashing it around for about 7 minutes (this is the 4th flight of this machine), the engine died while almost vertical. The x-spec with the MAH 690's autos extremely well,considering that the blades had virtually no headspeed when the engine died.

Upon inspection, the clunk line came off in flight causing the engine to die and I had a wobble in my clutch bell.

I split the frames today and here is what I found.

..the engine prop nut had backed out.
..one of the M4x10cs bolts holding the clutch shoe to the shaft sheared off
..all four of the m3x6 countersunk screws holding the fan to the starter pulley is MIA

What the [ ] happened here ?
How do I prevent this from happenning again ?

PM  EMAIL  GALLERY  Attn:RR  Quote
12-20-2003 06:14 PM  13 years agoPost 2
mrNoodles

rrProfessor

Borlänge, Sweden

My Posts: All  Forum  Topic

Sad to hear, I had the std. clunk tube break on my Freya, sharp edges on the pipes going in the tank Now Im using BlackHayes in my tank, also smoothend the edges on the pipes.

Never heard of other things that occured to you! Did you use locktite on the screws holding the fan?

Still sounds very strange! Could the prop nut backing off be the cause of it? The fan/flywheel got pushed up and stops due to the load pushing it upwards and the clutch screw cuts also due to the load being put on from the engine. Maybe the clunk breakage caused the nut to back off?! Just wild guesses!

Glad you got it down in piece though Besides that how do you like it so far

/Fredrik
'Hm now I just have to find out where to connect the GV1 sensor to the Jazz80 ESC.

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
12-20-2003 06:51 PM  13 years agoPost 3
elviswl

rrApprentice

Fort Lauderdale, South Florida

My Posts: All  Forum  Topic

Its an awesome machine. The power and responsiveness is incredible. This is my first 90 machine, so I am stoked.

What's really great about this machine so far, the current set-up has pretty fast cyclic response for stick banging, but it is also rock solid at the same time.

Hard to describe, but imagine great tic-toc and piro-flip responsiveness, then stable inverted piro-hover, with almost no corrections, almost as if expo kicked in just when you want it, and not there when you dont want it to be there. I fly with no expo and this thing tracks unbeleivable.

PM  EMAIL  GALLERY  Attn:RR  Quote
12-20-2003 10:26 PM  13 years agoPost 4
traderdave2

rrVeteran

Covington, GA

My Posts: All  Forum  Topic

Use something other than the stock fuel line. Use loctite on most everything.

The problem you have sounds like you put it together incorrectly. There is really no reason for the nut holding the fan on to come loose

What method did you used to tighten the nut on your motor.

You probably only had one thing come loose. The rest of the loose bolts were probably caused by the first loose screw.

Is the engine broken in.

Harlan

PM  EMAIL  GALLERY  Attn:RR  Quote
12-21-2003 02:24 AM  13 years agoPost 5
elviswl

rrApprentice

Fort Lauderdale, South Florida

My Posts: All  Forum  Topic

Harlan,

I used the MA Fan hub tool to hold the starter pulley while torquing the nut. I also think that the loose prop nut caused the other problems. The missing countersunk screws holding the fan to the starter pulley is still a mystery.

Its almost back together now; hopefully I didn't miss anything.

The engine has about five flights total, four just hovering, triming etc. really rich. After all the troubles to start the engine and the changes to my initial set-up, I banged the sticks a little, and was happy to see the results.

The prop nut probably came off from the starting problems and trying to start the engine while it was locked up.

PM  EMAIL  GALLERY  Attn:RR  Quote
12-21-2003 04:19 AM  13 years agoPost 6
traderdave2

rrVeteran

Covington, GA

My Posts: All  Forum  Topic

The tough starting might be a clue. You might have sheared the bolt while trying to turn the engine over while it was flooded. If you only broke the bolt then consider your self lucky. Better than bending a connecting rod. Those big engines can be really tough to turn when they get flooded. I used to turn mine over a little before I opened up the fuel line. I would start it as soon as I released the fuel. It doesn't take long to flood the engine.

I got rid if the flooding problems with a cline pump. It doesn't allow fuel to pass unless the engine is running.

Good luck with the rebuild. I will let you know if you miss anything.
Harlan

PM  EMAIL  GALLERY  Attn:RR  Quote
12-21-2003 04:53 AM  13 years agoPost 7
elviswl

rrApprentice

Fort Lauderdale, South Florida

My Posts: All  Forum  Topic

Finished the rebuild, tried cranking it over with the glow-plug out, it spins, and now its stuck.

I bet the nut backed out again.

I can't remember from the original build, but does the starter pulley screw on to the crankshaft. It was difficult to remove the last time, but it seemed to be where it should be.

Step 14 of the manual:
I used the starter pulley washer with the ys91. Is this right ?

I used the MA Fan hub tool to hold the starter pulley while torquing the nut; why is it backing out ?

PM  EMAIL  GALLERY  Attn:RR  Quote
12-21-2003 05:52 AM  13 years agoPost 8
Kona Chopper

rrKey Veteran

Kailua-Kona, Hawaii USA

My Posts: All  Forum  Topic

Probably a stupid question, but, did you install the YS crankshaft keyway before installing the fan.
Page 14, step 6 of the xspec manual. The starter pully washer also needs to be installed.



Why buy?? when you can borrow and no return

PM  EMAIL  GALLERY  Attn:RR  Quote
12-21-2003 09:40 AM  13 years agoPost 9
mrNoodles

rrProfessor

Borlänge, Sweden

My Posts: All  Forum  Topic

elwiswl
The starter pulley washer used with YS is real tight, a used sandpaper to increase the inner dia.
You did use the woodruff key right with the blue EX flywheel!?

/Fredrik
'Hm now I just have to find out where to connect the GV1 sensor to the Jazz80 ESC.

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
12-21-2003 03:22 PM  13 years agoPost 10
elviswl

rrApprentice

Fort Lauderdale, South Florida

My Posts: All  Forum  Topic

the woodruf key is installed.

Took the engine off and the nut is still installed. The problem seems to be engine related. I spun the fan by hand and the engine seemed to get stuck on the top of the up-stroke. I took the back plate off for inspection, and now, the engine does not get hung-up.

No idea what is happenning here !


BTW, the ys91 can be removed without spliting the frames. Remove throttle arm, engine needles, loosen frame brace nearest to engine. Remove fan shroud. You may also want to remove one of the bolt/nut in the frame channel for additional clearance. I took the engine out with the engine mount attached.

PM  EMAIL  GALLERY  Attn:RR  Quote
12-21-2003 06:00 PM  13 years agoPost 11
Alistair

rrKey Veteran

no where land

My Posts: All  Forum  Topic

frames never had to be split... unless you want to split them of course.

don't bother with removing needles etc... just remove the carb. then the bolts that hold the engine. pops right out.

when you put the carb. back on, make sure it is 50% throttle at mid-stick, max throttle at top-stick etc.

PM  EMAIL  GALLERY  Attn:RR  Quote
12-21-2003 08:06 PM  13 years agoPost 12
CCFlyer

rrNovice

Arroyo Grande, CA

My Posts: All  Forum  Topic

Elviswl,

Check the inside face of the engine backplate. If it's marred by the crankshaft connecting rod pin then the fan nut was never tightened enough. I saw this same problem with a friends Raptor /OS 70. He didn't get the nut tight enough and as soon as he pressed the starter down on the start shaft, the crankshaft moved and rubbed against the backplate. This could be the metallic sounds you heard before as well. Be sure the proper washer is on the engine. Hope this helps.

Scott

PM  EMAIL  Attn:RR  Quote
12-21-2003 11:32 PM  13 years agoPost 13
mrNoodles

rrProfessor

Borlänge, Sweden

My Posts: All  Forum  Topic

Alistair
Removing the carb from a YS is a PITA (at least while it still is in the heli )

elviswl
I think CCFlyer might be getting close to what happend. It may not been tightened enough due to the tight starter pulley washer on the YS crankshaft

/Fredrik
'Hm now I just have to find out where to connect the GV1 sensor to the Jazz80 ESC.

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
12-22-2003 04:23 AM  13 years agoPost 14
elviswl

rrApprentice

Fort Lauderdale, South Florida

My Posts: All  Forum  Topic

Thanks for all your responses.

Alistair
The OS carb removal is pretty easy, the YS is not so easy; its easier to remove the needles.

Today I encountered minor engine start-up problems, but I did two flights. Once started, the engine ran fine, still pretty rich with lots of smoke.

No idea why the engine would get hung up, and just be fine the next minute.

My start-up (YS 91) procedure consist of clamping off the fuel to the carb, glow-plug on, engage engine with starter, once started, unclamp fuel line, and remove glow-plug.


Question on the tail:
The tail would blow out during back-wards flight or funnels and do a 180deg turn. I am using a gy401 and 9253, gain at 70%. Is the belt tension too loose here ?

Thanks

PM  EMAIL  GALLERY  Attn:RR  Quote
12-22-2003 11:02 AM  13 years agoPost 15
Alistair

rrKey Veteran

no where land

My Posts: All  Forum  Topic

what tail blades are you using?

how hard are you loading the heli?

how low do you suspect the head to be when the tail lets go?

even a 601 will let go if you drag the head down enough.....

i would still think removing the carb would be quicker. four bolts right?
i hate splitting the frames unless i really have to. i don't like taking needles in and out either... i would rather remove the carb even if it's YS.

get an OS... ONE bolt

PM  EMAIL  GALLERY  Attn:RR  Quote
12-22-2003 11:15 AM  13 years agoPost 16
mrNoodles

rrProfessor

Borlänge, Sweden

My Posts: All  Forum  Topic

Be sure to remove the fuel tank first so you actually reaches the 4 screws

Pulling the hover needle is enough on a std. Freya, sure you have to turn and try some but it is possible

/Fredrik
'Hm now I just have to find out where to connect the GV1 sensor to the Jazz80 ESC.

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
12-22-2003 11:40 AM  13 years agoPost 17
Alistair

rrKey Veteran

no where land

My Posts: All  Forum  Topic

if you are going to pull the tank, you might as well split the frames.... i split the frames at the field, on a table that was anything but level... i wasn't having as much fun at that point

PM  EMAIL  GALLERY  Attn:RR  Quote
12-22-2003 12:46 PM  13 years agoPost 18
Kinger

rrElite Veteran

Granville, OH

My Posts: All  Forum  Topic

Could your tail blow out be related to the blue plastic tail fins used in the kit? I've heard these are not the greatest and should be replaced with a set of carbon tails.

PM  EMAIL  GALLERY  Attn:RR  Quote
12-22-2003 03:54 PM  13 years agoPost 19
Alistair

rrKey Veteran

no where land

My Posts: All  Forum  Topic

the plastic blue blades are not for me... it's not so much a blow-out i get with them, but more of a drift. i don't really fancy the way they feel. the tail moves 'round on me everytime durring high load/high speed stunts. especially sidesways flying.

the blue blades are thin, have a fairly narrow chord, and are a wee bit short... which wouldn't be so much of a problem if they were wider. which is what i would prefer to use on a freya. like a EX/WC feather only 90mm but a 31mm chord. and it's fat.. lol

PM  EMAIL  GALLERY  Attn:RR  Quote
12-22-2003 04:41 PM  13 years agoPost 20
elviswl

rrApprentice

Fort Lauderdale, South Florida

My Posts: All  Forum  Topic

The head speed is around 1900.

I am using the stock plastic blue tail blades. The mains are MAH 690 and I have a set of SAB 97mm, but I think that these blades may be a little too long for the x-spec.

PM  EMAIL  GALLERY  Attn:RR  Quote
WATCH
 2 pages [ <<    <    ( 1 )     2     NEXT    >> ] 1487 views POST REPLY
Scorpion Power Scorpion Power
HelicopterHIROBOOther › x-spec growing pains
 Print TOPIC  Make Suggestion 

 3  Topic Subscribe

Thursday, October 19 - 8:23 am - Copyright © 2000-2017 RunRyder   EMAILEnable Cookies

Login Here
 New Subscriptions 
 Buddies Online