RunRyder RC
WATCH
 2 pages [ <<    <    ( 1 )     2     NEXT    >> ] 2123 views POST REPLY
HomeRC & PowerAircraftHelicopterEngines Plugs Mufflers Fuel › YS vs OS when overheat on the piston
03-08-2010 11:40 AM  8 years agoPost 1
snowman999

rrNovice

nottingham

My Posts: All  Forum  Topic

People often talk about YS and OS, talk about different made quality and performance here. I want to share with you some of my personal experiexce with engines from these two leading brands.

The YS in the photo is a YS 91SR, it served for my Trex 700 over a year, went throught about 19-20 gallons of CP 30% fuel before it died. I overheated it once at about 15 gallon's age(my fault over clocked the needle by 1 turn!), after that accident it still starts the same way as normal and also no power decrease found, till the last flight at 19 gallons, I found obvious power short but it still completed its last flight without problem, *but* never starts again, what a tough boy it is! Took it apart, found a little bit of material missed on the corner of piston as you can see from the photo.

The OS in the photo is a OS HZ-PS, it served for my Trex 700 after my YS gone, for just 3 weeks, 4 gallons 1 overheat and it is done! I flew it twice:
week 1: set it rich, run it in for 2.5 gallons, all well and happy
week 2: didn't fly,but I forgot to draw the empty fuel out of the pump after week 1
week 3: Hard to start initially, started to lean the needle bit by bit for the performance. my fault again by misunderstood "one half turns" on mid,I overheated it and land. what almost made me cry was I barely can rotate the shaft by hand and it never ever starts again after just ONE overheat!!!!!
Took OS apart, OMG!the piston is like it's been fired deadly, some cracks and melts were found, big piece of corner turned into powder, also a big hole on the piston top face was created! that's incredible poor material compare to YS.

For my next engine, oh please NO OS again, although they are now releasing a regulated 91 HZ-R which looks pretty and sounds sweet, but as long as OS dont change their material, I wont buy one again.




PM  EMAIL  Attn:RR  Quote
03-08-2010 12:21 PM  8 years agoPost 2
Duckster

rrApprentice

Brunei

My Posts: All  Forum  Topic

Look at ur piston, the ys is barely black which says most of the time u running it lean, and when u look into the os piston bit white then ur ys, most os piston is good quality piston but if u overdo on leaning it, u will surely shorten the life, u actually have to learn by mistake then u will know, take it slow, i have used my os piston for more then a year but it is 50 size and got some slope on the top piston but still didnt broke yet but it loosing power.

For the 90 size dont be spoil by sweaty carb, u can hear and see if u run lean, especially on 700 the tail will wag if u run lean, but u need to learn how lean can u go, if u find it loosing power back to basic open both needle to 1.5 turn and retune, for my self since the 90 got lots of power i use to play safe by 1.5turn both needle and close around 3 click on high needle i know am still on the safe side, since am self sponsored pilot i better play safe and 90 has incredible power. Anyway it just IMHO

Trex 600,700 AND 450, GY611, GY401, OS5H, OS91HZ, MGP, HS65HB, Scorpion 2221-8,

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
03-08-2010 02:38 PM  8 years agoPost 3
WJackson

rrElite Veteran

Smyrna, Delaware

My Posts: All  Forum  Topic

Those pistons dont look that way due to any manufactoring defect. The person turning the needles did that. Tuning can be very tricky if you dont know what your doing or what to listen for. I would suggest you download the first episode from Smacktalkrc.com . Hate to say it, but it only takes one lean run, and you get what you have. I'm sure it was giving you all kinds of signs, but you maybe just dont know what to listen for. Sorry about your loss, but the engines are definitely not at fault here.

RIP Roman
Bill Jackson
AlignUSA

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
03-08-2010 02:45 PM  8 years agoPost 4
snowman999

rrNovice

nottingham

My Posts: All  Forum  Topic

thank you for your comment,I have to work out my turning skill to avoid damage the motor, you take care for it, it takes care for you.

PM  EMAIL  Attn:RR  Quote
03-08-2010 04:35 PM  8 years agoPost 5
Paul Woodcock

rrElite Veteran

Dubai - United Arab Emirates

My Posts: All  Forum  Topic

Hi

If my pistons looked like that, i would be too embarrassed to post pictures.

Try electrics, no tuning required.

Paul

PM  EMAIL  GALLERY  Attn:RR  Quote
03-08-2010 05:34 PM  8 years agoPost 6
Santiago P

rrProfessor

South West, Ohio

My Posts: All  Forum  Topic

snowman999

You should be called the "Charles Manson" of 91 heli engines. LOL

Joke aside, Interesting post, thanks.
You need to pay more attention to how your engines sound when running. Both of your pistons show signs of detonation (pitting). Lean VS rich have two distinctive sounds. A temp gun may also help you.
good luck

Santiago

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
03-08-2010 05:44 PM  8 years agoPost 7
GMPheli

rrElite Veteran

W. Bridgewater, MA USA

My Posts: All  Forum  Topic

You can't really draw any fair comparisons as you don't know how hot you got each motor. To test what you ask would have to be done under a controlled enviornment.

PM  EMAIL  GALLERY  Attn:RR  Quote
03-08-2010 05:57 PM  8 years agoPost 8
Zaneman007

rrElite Veteran

Texas - USA

My Posts: All  Forum  Topic

I have never seen that much damage done to a piston in just 4 gallons.

From the looks of it, I would have to agree with some of the other post, there is some serious tuning issues going on.

I am not the worlds greatest at tunning engines, I'm getting better, but..... man, you are making me look good, Thanks.

Old Guys Rule!

PM  EMAIL  GALLERY  Attn:RR  Quote
03-08-2010 06:16 PM  8 years agoPost 9
G Steyn

rrApprentice

Heidelberg, Transvaal, Suid Afrika

My Posts: All  Forum  Topic

Hi

If my pistons looked like that, i would be too embarrassed to post pictures.

Try electrics, no tuning required.

Paul

I do agree with that statement

Concentrate on your weaknesses and your strengths will reward you!

PM  EMAIL  GALLERY  Attn:RR  Quote
03-08-2010 06:45 PM  8 years agoPost 10
uk sailor

rrApprentice

UK

My Posts: All  Forum  Topic

The guy did say he had misunderstood the instructions, and if I read it right thought he should start with the mid half a turn out rather than one and a half turns out.
I also think he is saying that the YS appeared to him to withstand his admitted abuse, as GMP heli says it is unknown how hot each engine became, and a controlled test would be needed to know.

PM  EMAIL  Attn:RR  Quote
03-08-2010 08:45 PM  8 years agoPost 11
snowman999

rrNovice

nottingham

My Posts: All  Forum  Topic

uk sailor
I also think he is saying that the YS appeared to him to withstand his admitted abuse
that's what I wanted to say, thanks for pointing out

PM  EMAIL  Attn:RR  Quote
03-08-2010 10:01 PM  8 years agoPost 12
airdodger

rrElite Veteran

Johnston USA

My Posts: All  Forum  Topic

You don't need different piston material you need the ceramic tiles they use on the bottom of the Space Shuttle.

Chris

PM  EMAIL  GALLERY  Attn:RR  Quote
03-09-2010 02:56 AM  8 years agoPost 13
jb_turner

rrElite Veteran

USA

My Posts: All  Forum  Topic

User error... do not blame the product. Both OS and YS will last much longer with proper tuning.

JB "Do a SEARCH" Turner

PM  EMAIL  GALLERY  Attn:RR  Quote
03-09-2010 08:06 AM  8 years agoPost 14
uk sailor

rrApprentice

UK

My Posts: All  Forum  Topic

This guy has had the balls to say hey I have mishandled both of these engines. Yes possibly sufficiently badly space shuttle tiles might have been needed. More likely the Shuttle tiles would have come unglued! I am not aware he is blaming the engines so much as saying the OS APPEARED to let go quicker/easier than the YS.
It is clear this is not provable either way in terms of which piston held up better because it is not a controlled test.
I have holed the pistons on two OS engines, and it was my fault, but know from posts on here that I am far from alone in that. The Hyper had the carb modified by me and I was rushing the retuning.............oops flame out 30 feet up inverted. The other was an OS 70 which I leaned out too far but will say gave virtualy no warning a story again i've read before.
I think saying it's user error which the original post admits to and that he is blaming the engine which I didn't pick up on from his post gives no answer to the querry he was making. Namely do other people agree/disagee YS pistons hold up better than OS pistons given a tuning cock up.
Admittedly this is not the usual reason for choosing an engine, but then wait how many have slagged off OS for rear bearing issues in the hyper and haven't I read about the new 55 and HZ "letting go" for many users who don't think they are to blame. Many have then raised the question is another make better and jumped ship to the next brand as a result ?
For the record before it is thought/assumed to the contrary I have used various makes, and would buy any of them again. I have had a broken crank on a YS 50 which I don't see as operator error. A failed cage on the rear bearing of a Webra 61 when almost new, yet no OS bearing issues.
We all know any engine can give trouble, that all will be better for proper usage in all respects, including fuel,plug, compression, fan, fan shroud, rpm, etc etc blah blah, a lot of people due either to lack of skill/experience go a bit too far searching for more power, and many others are probably running very close to the edge.
I suspect the power the PRO's seem to have is a combination not only of good tune but better set up generaly and more skill on the sticks
My £'s worth, no wait with the current xchange rate better make that £2

PM  EMAIL  Attn:RR  Quote
03-09-2010 10:07 AM  8 years agoPost 15
snowman999

rrNovice

nottingham

My Posts: All  Forum  Topic

I am not an OS guy nor YS guy, I am always open mind for a good engine. I believe both engines are beast when they are proper turned. But when you make mistake in turning or say put it in an extreme lean condition, YS's piston seems to me that it has a better chance to servive. Just my 2penny, correct me if I am wrong.

PM  EMAIL  Attn:RR  Quote
03-09-2010 01:13 PM  8 years agoPost 16
uk sailor

rrApprentice

UK

My Posts: All  Forum  Topic

That's what I thought you were saying and my own experience would tend to support this, even if not scientific proof

PM  EMAIL  Attn:RR  Quote
03-09-2010 03:19 PM  8 years agoPost 17
bkervaski

rrElite Veteran

Birmingham, AL, USA

My Posts: All  Forum  Topic

Hardly conclusive as an indicator of quality, it would have to be the exact same amount of heat for the exact same amount of time. The OS may prevail if you reverse the conditions, no way to know. Suffice to say, you heat an engine up like that, it's going to break.

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
03-09-2010 04:23 PM  8 years agoPost 18
Santiago P

rrProfessor

South West, Ohio

My Posts: All  Forum  Topic

Hardly conclusive as an indicator of quality
True

In defence of snowman999, he already admited he has troubles with tunning. There is no need to beat him up any more. (two melted engines is enough punishment)

But I have to agree that drawing a conclusion from the mishapps is quite unfair. It does show that the OS piston will suffer more damage under harsh treatment. The end results is they are both dead, that one looks a bit more grim than the other is for giggles.
Both engines will last a long time if ran as MFG intended.

What is surprinsing to me is that these engines will ACTUALLY run long enough under these lean conditions to self destruct.
I have done it at least to one engine many years ago when a presuure fitting came loose. It took a few minutes and then...

When lean plank engines tent to just bog a quit, in helis you get full meltdown and an impressive show and tell item.

Always miss on the side of rich!

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
03-09-2010 05:15 PM  8 years agoPost 19
uk sailor

rrApprentice

UK

My Posts: All  Forum  Topic

Bit off topic but I allways wondered why heli engines melt down rather than quit like they do in a plank.

PM  EMAIL  Attn:RR  Quote
03-09-2010 05:23 PM  8 years agoPost 20
nivlek

rrProfessor

Norfolk England

My Posts: All  Forum  Topic

Castor oil would have saved both of those engines . If you had have drank a pint of it a day , you'd have never made it to the flying field .

At the end of the day , it gets dark .

PM  EMAIL  Attn:RR  Quote
WATCH
 2 pages [ <<    <    ( 1 )     2     NEXT    >> ] 2123 views POST REPLY
HomeRC & PowerAircraftHelicopterEngines Plugs Mufflers Fuel › YS vs OS when overheat on the piston
 Print TOPIC  Make Suggestion 

 8  Topic Subscribe

Tuesday, September 25 - 8:24 pm - 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