RunRyder RC
WATCH
 2 pages [ <<    <     1     ( 2 )    >    >> ] 1965 views POST REPLY
HomeAircraftHelicopterHelicopter Main Discussion › Broken con rod on OS 50 SX-H ... why ?
01-19-2016 04:37 PM  35 months agoPost 21
geomecc

rrKey Veteran

Long Island ,NY

My Posts: All  Forum  Topic

trying to crank a flooded engine by leaning the heli over towards the muffler and cranking untill it clears the hydro lock. instead of removing the glo plug and clearing the cylinder can break or weaken the con rod. it couldve even been a micro crack from manufacturing defect and over alittle time it spreads to failure.
the good thing is u got the heli down safely and no one got hurt

R I P Roman Jr. Team SKOOKUM SRW EFC

PM  EMAIL  GALLERY  Attn:RR  Quote
01-19-2016 05:05 PM  35 months agoPost 22
revmix

rrKey Veteran

NJ

My Posts: All  Forum  Topic

metal fatigue [weakness/stress]; sudden engine stoppage [blade strike]

PM  EMAIL  GALLERY  Attn:RR  Quote
01-19-2016 08:07 PM  35 months agoPost 23
dkshema

rrMaster

Cedar Rapids, IA

My Posts: All  Forum  Topic

Failed muffler bearings could also be related to defective connuter valves or an undertorqued doohickey which holds the frammis bracket in place.

-----
Dave

* Making the World Better -- One Helicopter at a time! *

Team Heliproz

PM  EMAIL  GALLERY  Attn:RR  Quote
01-19-2016 09:57 PM  35 months agoPost 24
wrongler

rrProfessor

Brewerton, New York

My Posts: All  Forum  Topic

^^^^Not True^^^^ LOL

The frammis bracket holds the thingamajiggy.

Bill Whittaker

PM  EMAIL  GALLERY  Attn:RR  Quote
01-20-2016 09:34 PM  35 months agoPost 25
Vaderluck

rrApprentice

Melbourne - Australia

My Posts: All  Forum  Topic

Thanks guys for the info.
I now realize broken con rod is a fact of life in nitro engine.
From you guys experience, how often it would happen. Because when it happens, it is expensive to replace all piston, ring, con rod, liner and maybe engine case too.

PM  EMAIL  GALLERY  Attn:RR  Quote
01-20-2016 10:14 PM  35 months agoPost 26
jschenck

rrProfessor

La Vista, NE.

My Posts: All  Forum  Topic

I now realize broken con rod is a fact of life in nitro engine.
No - conrod break, something didn't happen correctly - should never happen.

The most likely cause I'd bet is the flooded engine with a very strong starter. as stated in above posts

PM  EMAIL  GALLERY  Attn:RR  Quote
01-21-2016 12:54 AM  35 months agoPost 27
JuanRodriguez

rrProfessor

The Villages, Florida

My Posts: All  Forum  Topic

Thanks guys for the info.
I now realize broken con rod is a fact of life in nitro engine.
From you guys experience, how often it would happen. Because when it happens, it is expensive to replace all piston, ring, con rod, liner and maybe engine case too.
No , that is not true nor is it "common"..... there is a reason why it happened in your case.... it DOES NOT happen to most under normal circumstances.....

It has never happened to me......

Been there, done that and old enough to know better.....

PM  EMAIL  GALLERY  Attn:RR  Quote
01-21-2016 03:01 AM  35 months agoPost 28
Santiago P

rrProfessor

South West, Ohio

My Posts: All  Forum  Topic

I have broken several rods, 1 50SX, 1 Enya 60X, and a couple of older OS91s.
All during a lean run, and always at the bottom end after clearly grinding out the brass bush. The Enya was combination of overspeed and lean. All had that golden brown coked look. Yuk!

The lean runs were due to different causes related to the fuel system, i.e. pressure leak, cracked tanks, check valve stuck, debri in tank which clogged the needle, etc. Fly high powered nitros for over 30 years and you may get to experienced some of this crap.

I always run my engines on the rich side, but like I said, crap happens, and sometimes when it does, it will wipe out an engine in a hurry.

Santiago

Team Minicopter - PeakAircraft.com
bavarianDEMON- Team Kontronik - Scorpion Motors-

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
01-21-2016 11:21 PM  35 months agoPost 29
geomecc

rrKey Veteran

Long Island ,NY

My Posts: All  Forum  Topic

it happened to me once. all i fly is gas and nitro. its all good tho

R I P Roman Jr. Team SKOOKUM SRW EFC

PM  EMAIL  GALLERY  Attn:RR  Quote
01-22-2016 09:28 AM  35 months agoPost 30
datidun

rrElite Veteran

N Ireland

My Posts: All  Forum  Topic

Always thought if it was a lean run the piston would be all scored and the ring silver in colour,not the rod breaking because it was lean.

PM  EMAIL  GALLERY  Attn:RR  Quote
01-22-2016 08:16 PM  35 months agoPost 31
Four Stroker

rrElite Veteran

Atlanta

My Posts: All  Forum  Topic

Santiago;

I don't consider your description a "broken rod". Of course if you seize up the lower bushing it will take out the end of the rod.

PM  EMAIL  GALLERY  Attn:RR  Quote
01-22-2016 09:58 PM  35 months agoPost 32
meowguy

rrVeteran

Saco, ME

My Posts: All  Forum  Topic

trying to crank a flooded engine by leaning the heli over towards the muffler and cranking untill it clears the hydro lock. instead of removing the glo plug and clearing the cylinder can break or weaken the con rod.
I have done this too many times to count and it has never caused any issues at all. You pinch off the fuel, turn over a few times with the starter wand by hand, then put the starter to it.

The only issue you need to be careful of is fuel in the muffler causing a backfire when you do start the motor. That could blow out your muffler or blow off the muffler pressure line. So just tip the nose up when you're done and let the fuel run out before starting the motor.

You do have to think it through.

"Sweet dreams and flying machines in pieces on the ground." J. Taylor

PM  EMAIL  GALLERY  Attn:RR  Quote
01-23-2016 03:37 AM  35 months agoPost 33
artimus

rrKey Veteran

Buckley WA

My Posts: All  Forum  Topic

I dont know how many gallons of nitro I've poured out thru the muffler.
Your muffler bearings need to be chrome molly or the the your widget slips.

Fly Hard......Team Viagra

PM  EMAIL  GALLERY  Attn:RR  Quote
01-23-2016 11:46 AM  35 months agoPost 34
oballzz

rrNovice

lilburn ga usa

My Posts: All  Forum  Topic

Chrome molly muffler bearings are a must have or your widget does slip and we all know what happens after that........(it sends a signal to the flutter valve and activates the giggle switch!)

Music is probably the only real magic I have encountered in my life,it's pure and it's real,it moves,it heals..TP

PM  EMAIL  GALLERY  Attn:RR  Quote
01-23-2016 12:13 PM  35 months agoPost 35
banshee rider

rrApprentice

Phoenix AZ.

My Posts: All  Forum  Topic

I think it was caused by a loss of symmetrical fluid in his main blades which caused an out of balance condition in the drive train

ageing is manditory maturity is optional

PM  EMAIL  GALLERY  Attn:RR  Quote
01-23-2016 12:48 PM  35 months agoPost 36
1helimech

rrVeteran

NW Fla....

My Posts: All  Forum  Topic

Watch at YouTube

Enjoy ya'll

Good Day

I dream of a better world, A world where a chicken's crossing a road IS NOT questioned

PM  EMAIL  GALLERY  Attn:RR  Quote
01-23-2016 02:45 PM  35 months agoPost 37
kthane

rrVeteran

Pensacola

My Posts: All  Forum  Topic

Yes, but what is the brake rotor for? On a more serious note. It is likely the piston skirt broke first. And in all honesty sometimes these things just break.

PM  EMAIL  GALLERY  Attn:RR  Quote
01-23-2016 04:51 PM  35 months agoPost 38
ICUR1-2

rrElite Veteran

Ottawa, Ontario

My Posts: All  Forum  Topic

That video made perfect sense as to why the engine blew

the piston was installed backwards

spending time, paying attention

PM  EMAIL  GALLERY  Attn:RR  Quote
01-24-2016 03:10 AM  35 months agoPost 39
Santiago P

rrProfessor

South West, Ohio

My Posts: All  Forum  Topic

I don't consider your description a "broken rod". Of course if you seize up the lower bushing it will take out the end of the rod.
Hi Four Stroker,
I was not making a direct comparison with the OP, his rod failure is freakish, and mine were a combination of wear and lack of lubrication on the lower rod bushing as you noted. I was just saying that it happens.

I had one nasty overspin on a pylon racer, a Nelson Q40, Nose over on take off, prop broke, and I took too long to hit the shut off. Next thing you see is the entire spinner w backblate shot out like a bullet when the engine stopped.
it was a sad sight...

S

Team Minicopter - PeakAircraft.com
bavarianDEMON- Team Kontronik - Scorpion Motors-

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
01-25-2016 08:37 AM  35 months agoPost 40
myjane

rrApprentice

new zealand

My Posts: All  Forum  Topic

Way to lean , was it smoking during this flight

PM  EMAIL  GALLERY  Attn:RR  Quote
WATCH
 2 pages [ <<    <     1     ( 2 )    >    >> ] 1965 views POST REPLY
HomeAircraftHelicopterHelicopter Main Discussion › Broken con rod on OS 50 SX-H ... why ?
 Print TOPIC  Make Suggestion 

 12  Topic Subscribe

Thursday, December 13 - 3:39 am - Copyright © 2000-2018 RunRyder   EMAILEnable Cookies

The RC discussion world needs to consolidate. RR is now one choice for that. Its software is cutting edge. It hosts on-topic advertising. Help RR increase traffic buy making suggestions, posting in RR's new areas (sites) and by spreading the word.

The RunRyder Difference

• Category system to allow Rep/Vendor postings.
• Classifieds with sold (hidden) category.
• Classifieds with separate view new.
• Answer PMs offsite via email reply.
• Member gallery photos with advanced scripting.
• Gallery photo viewer integrated into postings.
• Highly refined search with advanced back end.
• Hosts its own high end fast response servers.
• Hosts thousands of HD event coverage videos.
• Rewrote entire code base with latest technology.
• No off-topic (annoying) click bait advertising.
Login Here
 New Subscriptions 
 Buddies Online