Conference vmszoo::rc

    
    
    To answer Bill's question..
    
    NO, I don't think that it was a "LEAN" engine run problem. Rather
    the original SF series have shown a tendency to destruct the rear
    barings. From what I've heard it a size and quality issue more than
    anything else. 
    
    OS originally denied that there was any problem with this series
    of engine. But of late they now have a warranty that will replace
    any OS failures if the engine is purchased within some minimum time.
    Interesting is that OS has redesigned the SF 61 side and rear exhaust.
    You can tell the older engine from the new by looking at the engine
    casting where the rear baring in located. This is just rear of the
    carb and adjacent to the front of the cylinder. The old engine has
    a pronounced ridge while the new engine shows barely any ridge.
    If you hold up the old with the new the change is quite evident.
    Some of the folks at the meet were still running the old Sf but
    with an aftermarket baring. Also OS now will sell you a brand new
    casting with a set of new barings for 67.00 but refuse to acknowledge
    that there is any problem or repair (their cost) any blown engines.
    
    I saw some of the new OS 61 RE Pumped engines and they do run great.
    They had a number of flights on them and show no signs of any problem.
    I'm in the market for a pumped 61 and will probably buy the new
    OS. I guess that says I think they've fixed the problems. I also
    heard some bad news about the new YS 61 longstrokes.
    
    Seems that this design is having problems. The word out is that
    when you purchase a new engine to then need to disassemble it and
    purchase an aftermarked connecting rod and an aftermarket rear baring.
    Seems that as designed the connecting rod is all aluminum with no
    bushings and the rear baring is a sealed baring on both sides.
    Seems that the rod will last app.20 flights before showing signs
    of wear and the baring doesn't last that long. Also the word is
    that YS is in the process of a redesign of this engine.  
    
    
    The only other item is that the OS barings rust easily. Everyone
    cautioned to run the engine with the flow line pinched off with
    the glow plug on. Both hand flipping and with a electrical started
    at the end of a flying session. They went further and said that
    after the run out an after lube is needed and that putting oil 
    into the carb opening wasn't enough. Rather the engine needs to
    be flipped over a number of times and then with the fuse pointing
    down flipped some additional times. Then the fuse should be stored
    in a nose down attitude.
    
    
    
    
    Tom

    I just checked with Towers and they have the New OS 61 RE Pumper
    for 179.95 + shipping. Does anyone know anywhere else that sells
    these and maybe a price? I know Towers is the importer. Are they
    the cheapest?
    
    
    Tom

Suppose I got a new OS .61 pumper.  

Would I want to spend any extra for the ABC?

Will it withstand my abuse (maladjustments) any better
than without the ABC?

OS advertises the same horsepower for plain and ABC?

Is it harder to break in?

    I have had nothing but good luck so far with my SF engines. A .40 thats
    seen about 200 flights, a .46 thats seen about 50 flights, and the
    .61 pumper that has about 20-25 flights on it. The .40 and .46 are
    ringed, while the .61 is an ABC. The .40 and .46 have been flawless
    powerful, and quiet. The .61 puts out a lot of power and runs well
    at the low and high end. Mid range is a tad rich, but I believe that
    after it's better broken in, and I fiddle with the carb, it will be
    perfect. I have added a OS/JTEC snuffler to it which gave it increased
    RPM, and quieted it down a lot from the stock useless muffler. I have
    no complaints, and expect none. My experiance with both automotive and
    motorcycle engines is that if you want them to run well in all RPM
    ranges, leave it stock. Soon as you start playing with performance
    improvements, some area or areas will suffer, and you have to constantly
    screw with it all the time to keep it running at peak performance.
    
    I still believe the old adage....
    
       " There is no replacement for displacement "
    
    In other words, want more power, put in a bigger engine.
    
    
    							Dave
    

>    perfect. I have added a OS/JTEC snuffler to it which gave it increased
>    RPM, and quieted it down a lot from the stock useless muffler. I have

Dave - was that a complete replacement or one of those upgrade things
where you remove the back 1/2 of the stock muffler?

If it was the full replacement - why didn't you get just the back half?

These questions from a confused reader of catalogues.

Bye          --+--
Kay R. Fisher  |
---------------O---------------
================================================================================

    Kay, I'd say the OS 61 ABC Pumperr is timed for a pipe. You won't
    get the power out of it inless it's piped.
    
    
    Eric, What OS61 RE PUMPed engine do you have? Is thers a pronounced
    ridge where the rear baring is located in the case? 
    
    I heard horor stories about the original SF and have first hand
    experience. I also was a minimum of 6 stock new SF pumpers this
    past weekend and they all ran like champs. They were running long
    pipes and the new APC props at 9-10K RPM's.
    
    
    I called TOWERS yesterday and they said the OS 61 REP's are out
    of stock until mid Oct. SHIT!!
    
    
    
    Tom

>    The ABC or not ABC, to be Shakespearian for a moment, is a power
>    choice. The ABC being more powerfull. With ABC it is also harder to 
>    seize the piston but they do not last as long as the ringed engines. 
>    In your case Kay, with your reputation for meticulous engine care,
>    I am sure you could be the exception to both of those rules. (Joke).

I'm not joking - I'm serious.  Assuming I am willing to pay the extra
for ABC (big assumption right now).

Then which is best for someone who just wants to fuel up and go.
That is someone who will fly on 0 to 12% fuel (12% - evaporation)
and someone who only adjusts when forced to - and frequently
forgets after run oil - etc.

Would the ABC be more forgiving for more finicky?
Which has less damage and why in a lean run?

Will the pump help a novice make engine adjustments and
tank position problems smaller or will it add a level of
difficulty that he (I) don't need?

Bye          --+--
Kay R. Fisher  |
---------------O---------------
================================================================================

    A lot of these replies seem to be directed at a single, new design
    engine that does appear to have some problems. Lest people who are
    less familiar with the topic begin to think that they should avoid
    OS, we need to balance the issue.

    I have 3 OS engines: .35FP, .25FSR, and .45FSR. They all have served me
    well. They all have hundreds of flights on them, and have given me NO
    problems. I've never opened one up (the 35FP has been sitting on my
    retired trainer for a couple years and developed a little rust that
    seized it, it will need a clean-out before putting it back in service). 

    These engines start with 1 or 2 flips. They rarely need needle valve
    adjustment (only a click or two depending on weather conditions). I
    haven't had one quit in flight (except last week when I ran it out of
    fuel) for months. The only times I've had problems they were traced to
    fuel/tank/fuel lines, never an engine problem. Once or twice I ran them
    too lean; I think I remember the 35 seizing once during flight for this
    problem (overheating), but after cooling off a few minutes it started
    right up and ran fine afterward. 

    Unfortunately, OS has obsoleted the FSR line in favor of the new SF and
    RF motors. FSRs can still be found. It makes sense that there may be a
    few bugs that need to get worked out of the new design (spending my
    career in design engineering, I'm well aware of that fact). But I
    haven't heard any negative comments about the new design except for the
    61.

    I will point out that at the end of each flying session, I burn out any
    remaining fuel (fuel line removed, glow battery on, flip it until it
    won't fire). Then I put a few squirts of WD40 in the carb and give it a
    few flips. If I'm going to store it for a while, I use Mystery Oil (it's
    thicker and stays in place better). This must be done religiously.
    Leaving raw fuel in an engine is an invitation to rust, and it doesn't
    matter what manufacturer. 

    My recommendation to anybody considering an engine purchase: Except for
    the specific (rare) exceptions noted by other replies to this note,
    OS is an excellent manufacturer.

    Al Casey - do you have a few more words on the subject?

    Dave

    
>>Then which is best for someone who just wants to fuel up and go.
>>That is someone who will fly on 0 to 12% fuel (12% - evaporation)
>>and someone who only adjusts when forced to - and frequently
>>forgets after run oil - etc.

    A cheapo FP-type engine with rings and no bearings would be the best
    choice for this person.  Rings because they last longer.  No bearings
    because they will rust the first time you forget to burn out raw fuel
    and add after-run oil.
    
>>Would the ABC be more forgiving for more finicky?
>>Which has less damage and why in a lean run?

    I don't know the answer to this, but Eric seemed to indicate that it
    is harder to sieze an ABC.  Either way, lean runs are going to take
    life from your engine.
    
>>Will the pump help a novice make engine adjustments and
>>tank position problems smaller or will it add a level of
>>difficulty that he (I) don't need?

    If you don't need every ounce of power and can locate your fuel tank
    in a reasonable location,  I'd say forget the pump.  The fewer parts
    to fail the better.  I don't think the pump will help with engine
    adjustments, except that you should set your needle a tad richer
    without a pump to allow for leaning out as the fuel tank gets low.
    
    Bill

    
    I agree (as I know most people do) with Dave's comments about the
    general quality of OS engines.  That's why I was surprised to hear
    about the 61 SF troubles.  Lately though, I'm starting to think that
    OS is getting carried away with their prices.  $150 for a 61 SF?!?
    For half the price I got an ASP 61 FSR, and I've looked it over
    (and talked to Harvey Thomasian about it) enough to be convinced
    that I didn't get half the quality.  In general I believe in the
    "you get what you pay for" theory but it seems that OS knows they
    have a captive audience and can still get people to buy their engines
    even if they are overpriced.  Comments?
    
    Bill (who thought he'd never buy anything but OS)

I have said many times it is a fallacy that a ringed engine lasts longer than
an ABC, even if they do the difference is immaterial as the expected life of a
2 stroke engine properly looked after is longer than you are prepared to put
fuel into it. 

Think about this; with a ringed engine there is drag all the time because of
the constant pressure the ring exerts against the bore. With ABC it is a free
loose fit for majority of the stroke only becoming a neat fit at the last few
degrees of the cycle. 

The ringed engine potentially has more hassle than the ABC. Rings can jam quite 
easily. I suspect many of the engine problems discussed in this conference are 
due to ring problems.

Properly cared for the ABC can give better service than the ringed motor. Refer
to note 289.0 for more info on care. 

John

    
    
    I think that for the most part OS is a well made engine. Granted
    they have had and will have problems they are as good or better
    than most anything on the market.
    
    I'm talking OS61 REP and OS61SF. Mine was a side exhaust 61 ABC.
    
    Eric, I'd bet ya yours are the older version as the newer version
    has only been on the shelves for a month or two. They are running
    pipes in the 17" range with props of 12/12-12/14. The new APC 
    prop did look interesting. Seemed like everyone in the higher
    classes was running this prop. They are also running a lot of
    Hatori pipes and all rubber mounted engines.
    
    The new engine exhibits a slight step down on the outside of the
    case where the rear baring goes of appp. 1/32". The old engine
    has a step of app 1/16 or more. This reduced step supports the
    installation of a larger baring. Interesting is the fact that OS
    used the same baring in the original (old) longstrokes as is in
    the FSR. They had no reason to think that the engine would fail.
    I guess they underestimated the power of the longstroke.  
    
    Everyone running the newer version liked them and had O (ZERO)
    problems. Guess OS fixed their problem. I to am disappointed with
    OS for not standing behind a manufacturing defect. I own two OS61
    SF sides.  I will be buying a new OS 61 REP when they come available.
    
    I haven't heard anything good about the new longstroke YS 61.
    It a;so seems funny that no one runs the Enya. 
    
    
    Eric, What class in AMA pattern would you fly?
    
    
    
    i have newer taken good care of my power plants. I'm one to fly
    then store a plane without thought to the engine. I think I'm changing
    my mind. What does everyone use for afterrun oil?
    
    
    Tom

    To try and clear up what to be looking for on the OS61, I was looking
    at a side exhaust last night and the ridge on the outside of the
    casting where the rear baring goes is almost the size of a mold
    release line. The older engine has a pronounced ridge.
    
    
    Tom
    
    

    
    
    Al,   Off subject but.....
    
    	The YS engines used were two types. The std YS is most commonly
    used box stock while the newer YSLS (long stroke) is highly modified.
    At that level I guess you can affort to but three or four YSLS
    engines at 280 a pop and then put 150.00 per engine into them for
    new pistons,liners and con rods. 
    
    	The new OS Long Stroke Pumper is being run box stock.
        The older OS Long Stroke Pumpers or no pump are being run
    with a different set of barings.
    
    
    Tom       
    	

    I'm interested in purchasing a FS 48 Surpass. The idea is to install
    it in a 25 sized pattern ship. What kind of power and reliability
    has anyone seen?
    
    
    Also what props are being run?
    
    
    					   Regards
    
    
    					Tom	

    There is a lot of traffic on the rec.model.rc Usenet group about OS
    shutting down and possibly being reorg'd/bought out. The initial
    message was 01-Apr-1991 so I was immediately suspect. Several follow on
    messages have claimed it to be true, just bad timing on the posting. I
    was wondering if anyone here in the file could confirm/deny the rumor.

I got some information from the local hobby shop and thought I had posted it 
here someplace but don't remember if I did or not. What I have heard from the 
local hobby shop owner is this:


The owner of OS main interest is large scale live steam locomotives. He produces
them in addition to the motor works. He's wealthy and the motor works is just a 
side line now days. The workers at the motor works decided to go on strike for 
higher wages. The owner decided he didn't need the headache and has shut the plant 
down for a year. 

That's what I've heard and if true it wouldn't be too hard to imagine the motor
works being sold off. But what I've heard is just a rumor. Maybe there's a
Japanese RC Noter out there who could give us a better perspective?

    An interesting thing I found was that OS .25FPs are 8-9gms lighter than
    .20s and produce more HP with the exact same dimensions. I bought a
    pair for my P-38 (that I MIGHT one day start on)
    
    Just a datapoint to consider

    I was asked the other dy if I had heard anything about OS no
    longer producing engines....  I had not heard anything about it...
    
    Can anyone confirm what their status is??  If they are not going to
    be making them any more, have they sold their molds to anyone??
    
    Thanks!
    jeff
    

    Well Jeff if the lead time on their engines is anything to go by ....
    
    Orders seem to take an age - spare parts is not far off either.
    
    So has anyone heard what is happening with the OS engine line ?
    
    Having seen the prices of the model locomotives I would have thought
    that the market for Aero etc engines would have been bigger and have
    better sales that the loco's. They must need to sell a mucho anount
    of the standard engines to match 1 loco sale. I had the prices of them
    somewhere - but where ? 
    
    Eric.

    I heard that the owner of OS is a rich asian who does OS as a hobby.
    He is curently in a dispute over employee wages (strike) , and basicaly
    said " screw them , I don't need the headaches , sell the company- sell
    it all of it"
    
    Bob in Bluebell,Pa.

    I am asian, but I sure am not rich. :-(
    
    ajai

    Well,  The latest here from my local hobby shop is that he got his
    invoice from OS over a month ago and paid the $$$$ and is still waiting
    for a reply or product. He says that normally OS issue an invoice at
    about the time that the goods ready - but no such luck this time. 
    
    He has resulted in sending a couple of FAX's to OS in Japan but no reply 
    - must have beamed them into outer space ! 
    
    Any chance that they are in the middle of a wake out there - I hear
    that these thinks go on, and on, and on. That was my locals suggestion
    to the delays !  I am waiting on another OS91 4-S for my Wots-Wot.
    
    Do we have some local Japanese RCers listening ? 
    
    Eric.