dragunov80

And I thought OS 50 SX was supposed to be a reliable engine.....Its expensive and I bought it bcoz I know that in advance level planes, one cannot afford to have a dead stick.... I lost my beautiful brand new Imagine 50 bcoz the engine died at the top of a low altitude loop and the plane just could not recover.....well... I wonder why people say that O.S is reliable.....[&o]

Connery

I wouldn't be blaming the engine so quickly. I have an OS 40 FP that is about 18 years old that STILL starts on the first flip and runs great. There are a multitude of things that could have made the engine stop running, and they are all pilot induced failures. Most likely you leaned the engine out too much before you took off and as the engine heated up, and you increased in altitude you leaned out even more and it died. Another possibility is that you made the clunk line in the fuel tank too long and when you inverted at the top of the loop, the clunk didn't fall and the engine ran out of fuel.

johnboyrc

My 50 sx works great, and is reliable, like how good an engine it is. With proper care/maintance, your engine shouldn't give much if any trouble. Are you sure it wasn't a fuel problem -position of the tank, or a glow plug going bad (or even wrong temp). If your tank is too low or a distance from the engine, making a loop with your plane will let you know quickly. Often blame gets directed right away without checking for the cause first. Seen too many do that here, I thought it would be imbarassing for people to do that. Check it out and see if you find anything.

thewrap

my f@%# os 40 isnt any better. i run it rich it dies i run it lean it dies. no matter where i run it it dies.
I have a 30 year old motor that runs better than it does.

s. wallace

My Feedback: (24)

My OS 50SX in an MK Alliance sport pattern model has never missed a beat in over 200 flights over 3 years.
I changed the plug once in all that flying (OS#8) after the 2nd season just as a precaution.

You CAN find other brands that may be more powerful per given displacment...you cannot find a more reliable 2 cycle engine than OS.

dragunov80, I am sorry for the loss of your nice model but set that engine up with good fuel, a good plug and set a few clicks rich it is pretty much bullet proof.

dragunov80

well guys....building a plane is hard work....I spent many days building the kit....then how could I have flown it without checking everything.....I checked the fuel tank five times.....fuel pipes...may be 10 times....brand new glow plug....and the fuel I have been using on other models for a long time....never had a problem with other engines.....I have two 50 SX both have air leakage around the needle valve....a lot of bubbles between the needle and carburator fuel pipe....I have a magnum xls 46 which is 1/4 price of O.S...I never had a dead stick with that although i dont even care for it....so I dont feel EMBARASSED to speak the truth...it was the engine...as far as the crash is concerned....well its part of the game....

dragunov80

By the way....A day before the plane looked somewhat like this......

RC-Captain

Sorry about your crash [:@] but I have 2 OS engines that never flame out unless they are out of fuel. Is the plane 3D ? I am asking because it looks small for a .50 motor.

charrua

My Feedback: (47)

I don't think it has anything to do with Os engine I also have the 50sx and it's great,, if you break em in right they will run forever and not give you any problems, I'm an OS fan and that's al I have run, because I had bad experience with other engines so I stick with OS, I had a 40;46;50 and 1.60fx 2 strokes also a 40FS and a 1.20 III Surpass FS,, never had any dead stick on any of this engines!!!!

Somethime if you are too lean or too reach somewhere they will quit on some of those manouvers.

By the way SORRY for your loss!!!

BDAD Flyer

My Feedback: (15)

I think its just foolish to blame it all on the engine.... just my opinion.

MinotRich

Did you break this engine in at all on the ground before flying it? There is no mention of this in your post. Before you blame OS for a faulty product, I would ask you what kind of break in procedure you used prior to flying. Also, by your own admission, it died "at the top of a low altitude loop." Perhaps you should have had more altitude when attempting such a maneuver.
I understand your frustration, and sorry for your loss, but look at the facts (or lack thereof, in this case). Don't be so quick to blame an engine manufacturer unless you provide all the facts first.
I have several OS engines and in my opinion there is no better engine for the money. They always start and run great right out of the box, with no frustration or fiddling with them. A little TLC and a couple of tanks to "break them in" on the ground, and you have a dependable engine you can fly with no fears. Try that with any other brand and I believe you'll surely be disappointed. But then again, you get what you pay for, or... "you only get out of it what you put into it..." Rich

smokingcrater

irvine??? OS has had a couple reliability issues in the past, anyone remember the peeling liners?

drumbum

My Feedback: (1)

I have broken every motor i have ever had in the air and have never had a problem with an os engine since i have been flying, since 1985.. i have with other brands but on those where just bad apples and either got replaced or repaired.. i havent had a bad motor in about 10 years now.. especially 4 stroke in which i have yet to have one.. oh and i also have never used any after run oil in anything ive owned either.. I have an OS 25 FP that i first had on a plane around 1985, it still runs fine .

dragunov80

well....guys sorry for all those comments....today I found out the root of the problem.....thats what i was worried about, that all my other O.S engines are fine then why 50 SX is not reliable.....today I found out...

I installed the same engine in my Majestic 1400 and at the first two flights it had the same problems.....then I realized that even with extremely rich setting the engine is heating up....then I took off the cowl and the engine became a power house....10 flights and not a single problem.....The weather here is too hot.....and the engine had only a small amount of its heads exposed to the air.....even smaller head exposure was there when it was installed on Imagine....I had no idea that the cowl can make the engine to heat up....so if you are living in hot regions do not put cowl specially with new engines.....

as far as the break in is concerned, it was perfect.....8 fuel tanks full rich which means approx 2 hours of break-in time....

Well guys thanks alot for the replies....and now that I have found out the problem I DONT BLAME O.S ANY MORE.....sorry if I hurt anyone's feeling....

DRAGUNOV.

bruce88123

No hurt feelings, just glad you found the problem before losing another plane. My OS 50 also performs well but is also in open air and cooled well. A strong motor for it's size, keep it cool and you will like it.

campbec

I disagree,

It has nothing to do with the motor or overheating.

The Gods of aeromodeling were offended that you took a photo of the Imagine before its' maiden flight. Any model must be maidened before photos are taken or you will pay the price (construction photos don't appear to trigger the curse).

Cheers,

Colin

RC-Captain

I would bet this is the same answer to the problem I am having with my MAG .28 . When I first got it I flew the Extra 300 with the cowl off , no flame out for 2 flights . Then I put the cowl on and to date it flames out about half tank. [:@] This weekend the cowl is coming off.

50%plane

My Feedback: (5)

I always try to follow the 3:1 rule when it comes to cowl openings. ( the air exit hole is three times bigger than the air entry hole)

althepal

Yes, exit three times larger than inlet, that is the key...Had a decathlon where the engine(OS 46 SF with inverted J-tec incowl muffler), ran great without cowling, but died after a few minutes when cowled...tried to make a cowl flap, did not work, only when I did open a nice hole at the bottom of the cowl it was doing ok. Friens of minee had a sterling WACO with a fox 50...radial cowl open all the way in front, but no exit holes for the hot air to go...same problem, and there the whole front of the cylinder was exposed to airflow, but no way out for the hot air....A cowling can actually increase efficency of cooling, addition of a baffle around the engine can force air on cylinder, but all of that to no avail if no exit is provided. may be just my 2 cents, bt works for me

CJKling

My Feedback: (1)

I always cut away the entire bottom of the cowl, as much as you can without destroying the look of the plane from the top, you can't ever have too much breathing room.

KaosDriver

Deadsticks are inevitable. The law of averages catches up to us sooner or later. I don't know what caused this one, but I can speak of O.S. engines. My first experiences in R/C dealt with the FP's. I didn't know anything about break-in. I just filled the tank and flew. Remarkably reliable even so. Each experience with O.S. as a beginner was the same. I only had to deal with deadsticks via fuel starvation. I thought all engines must be the same. How I've learned! I've also learned that no matter how many times I check the systems, Murphy's Law still applies. The only fault I've found with O.S. in 20 years is the price, nothing else. Sorry about your loss....you'll never know the cause, so put the "fifty" back in the air.

ICE_MAN

Hehe I on the other hand don't Like O.S.'s ... My Dad has a O.S. .46 SF with pump that runs well.. However after fiddling with other newer O.S.'s I'll never own one unless it's maybe a 1.60FX...

Other than that my ST's are stronger and more reliable than the other O.S.'s at the field!

3dman523

My Feedback: (1)

I love o.s. engines. Every one ive had runs great. Sorry about your loss.

horace315

My Feedback: (15)

i use a lot of different engines and at one time or another have had an engine shut off be-it low fuel,lean hot or whatever.every time i take off the ground i know something might happen it is part of the sport.you can check and recheck and try to make sure that you haven't missed anything it happens,some engines are more reliable than others,OS has a pretty good reputation for reliability even the best engine can have a problem.,,,sorry for your loss ....happy flying

car147

Glad you found the fault, and had the guts to re-post, a lot dont!

In my experiance, apart from during the break in period i have had no problems whatsoever with OS engines.

Have fun.