Jesse Open

Sure thing O.S. is not much different in that they stretch things a bit. Just about all of them have.
What with so few engine makers left, we can be thankful they are still building and selling.

Jesse Open

Back in the hey-day of pattern contests, the sponsorships were fat with cash and the horsepower wars got pretty wild.
There were plenty of RC magazines just loaded with advertisements.

If not for military and research drones, a good chance that the people now in the biz would have shuttered and closed long ago.

1967brutus

FWIW, it wasn't about that....

2W0EPI

100% agreed!

the Wasp

My Feedback: (1)

just as I was suggesting,

Nib k&b 40 r/c. - RC Groups

sold, but and wondering if his price was met.
NIB Supertigre GS40 #SUPG0122, Nice! - RC Groups

Eastflight

Are you going to buy the 52 or not bother now?

2W0EPI

I'm not going to do anything yet, but in the near future there is a strong possibility that I will buy the Force 52 engine. I've checked my supplier and is currently out of stock.

1967brutus

JustEngines?

2W0EPI

There are plenty of suppliers that have the 52 in stock but the best price is from rcworld, unfortunately 'just engines' are a little high priced for me but there is no rush... I can wait.

Eastflight

https://www.modelshopleeds.co.uk/cat...ducts_id=58287

Try Leeds Model Shop - x1 in Stock at the moment

Jesse Open

Wow, only $135.00 US, a very attractive price.

2W0EPI

Check this price, some have straight or canted needle valves..

.https://www.rcworld.co.uk/acatalog/Force-Engines.html

Eastflight

Yes that link shows the previous model with the straight carb set-up. The one at Leeds Model Shop is the better version with purple head and swept needle config for an extra five quid.
Go on....you know you want it !!
When the new supplies come in to port from Asia, for sure they will be a bit more expensive in the shops!

Jesse Open

Nice looking engine, Taiwan quality is darn good too.

2W0EPI

Maybe here then: https://www.morrisminimotors.com/jp-...ne-8-52cc.html

Eastflight

Okay, You got me :-).
That's a really good discounted price with free shipping.

2W0EPI

This is an excellent thread because an internet search of a os 46axii and a Force 46 shows little information about these two engines, however the F46 goes for around £85 whilst the OS 46 AXII costs about £130~£140 depending where you buy it from. Both engines produce about [email protected] so engine life is going to be about same. I just want to point out that engine manufactures can easily kick out more power at higher rev band but this will unduly result in shorter engine life so keep the rpm specs as low as possible.The OS 46 AXII offer a 2 year warranty on this engine which gives some indication of how long the OS engine will last.

I do not have any experiences with the OS 46AXII engine but I do have a F46 and I found it to run okay, in particular when buying new check all the nuts and bolts are tight and I have found that the optimum operating conditions of the needle valve is 1/4 open, whilst initial starting requires the needle to be a full 2 turns out(rich). Once the engine has started decrease the needle valve towards 1/4 open at the same time reduce the servo throttle to bring the engine down to about 3000~4000 rpm idle then remove the glow starter from the glow plug. During break in I have used both a hot and cold plugs and have yet to see any difference between the two.I did notice that the hot plug glows a lot brighter than the cold plug.

Also, I notice the fuel lasts a lot longer when the engine is running 1/4 open(lean) and there is a lot less castor oil spraying out of the exhaust.

1967brutus

With the needle 1/4 turn open, you won't get much power, that is way too lean for full throttle. Normally the HS needle should be at least 1~1-1/4th turn open for the average .45 and that usually is allready on the lean side,
The rich running at reduced throttle should be adjusted with the LS needle, not with the HS needle

Eastflight

My knowledge of Force 46 is pretty limited however I have been using the OS46AX & 46AX ii for many years. They run extremely well once broken-in and when set up correctly.
In fact I hardly ever touch the High Speed fuel needle (maybe two or three clicks at most if I change the fuel %) and I never touch the idle screw (LS) setting at all once tuned. Bearing in mind the F46 and OS46 are from the 'same page' I would have thought the settings are VERY similar. My needle valve is set to 1 3/4 turns which is a bit rich but still very snappy from idle to max throttle (I run them hard depending on the aircraft I'm flying). No spurting or coughing at all.
It burns pretty clean on Optifuel 12% Nitro. I also use 5% but with little or no gain in fuel consumption however, it does gives a slightly better idle on 12% using an OS Hot or Medium Plug (I also use Redline or Fox plugs depending what's in my field box on the day).
When you say you didn't see any difference with the plugs during break-in (hot or cold), I don't think you would.
Most people use an old plug to break-in and until the engine is fully set up correctly, only then can you make a comparison IMO.
Having said all of that, I'm sure the F46 is a good engine for the price but until I try one for myself - only then can I compare BUT for now I'll stick with my OS46 & Irvine 46.

2W0EPI

Yes Brutus you are correct, its too lean when revving up the engine it died, so I opened the needle valve to 3/4 turn and found it revved up to high rpm and then dropped back to idle. The only problem is it coughs and splutters at idle, I tried adjusting the idle screw but didn't notice any change so I left it as it was.

Another problem I have is it is very difficult to start from cold, can't seem to get fuel into the carb and when I do it floods.

Eastflight, your OS 46 seems to have a better running characteristic than the F46, I'm thinking of buying an OS 46AXII just see if the high cost is warranted or not?

Cheers

1967brutus

Get your HS needle open AT LEAST 1.5 turn, probably that is still too lean. Better to open it 2 turns or more, go to full throttle, and gradually close the needle untill you notice RPM does not increase anymore, then open the needle back up about 1/4th turn. or at the minimum where you hear RPM fall off just a smidgen. Do NOT lean out untill the RPM falls off, ALWAYS go a touch rich. ALWAYS...
THAT is how you set a high speed needle.

The low speed needle most likely is still way too rich, but the question is given your level of experience (and do NOT mean this snarky or condescending) whether you turned the correct idle screw. There are two: One limits the stroke of the throttle barrel. If you close the throttle, and
turn the screw that is pointing upwards close to the air intake opening, you will at some point see that it forces the throttle open. That is your idle stop screw, it is intended to set a minimum throttle, but in reality, nobody uses it, it generally is unscrewed so far that the throttle can be JUST fully closed. No less, no more. Idle speed is adjusted via the transmitter, by means of throttle trim.
The idle screw that you SHOULD adjust is located IN the centre of the throttle LEVER. If full speed is adjusted as described above, gradually close the throttle until the engine starts to sputter, then close (turn clockwise) that adjuster by about 1/8th turn at a time until the running behaviour clears up. Do NOT adjust until the engine runs smooth, ONLY turn clockwise, 1/8th of a turn at a time, with 5 to 10 seconds inbetween adjustments, untill you notice that the engine responds. Then close the throttle a little bit further, and repeat. Work your way down all the way until you have a steady idling engine at a throttle opening of about 1 mm visible gap in the air intake (in inches, this is about 5/128th). Now leave the engine idling for about 20 seconds, then jam open the throttle in one go, and observe how it accelerates. If it hesitates then picks up, idle is a touch too lean, open the idle adjustment by about 1/16th and try again, continue until it picks up in one go.
If it straightaway dies, it is too lean, open 1/8th and try again.
If it stutters and picks up with a delay, it is too rich and the adjuster should be closed a bit more (1/16~1/8).

After you have done this,, your starting problems also should be history.

2W0EPI

Thanks for the explanation and info, it's raining right now so I'll try again tomorrow.Thank you Brutus, you are a very knowledgeable guy,

Cheers for now

jaka54

Hi!
Agree fully to what Brutus 1967 says on setting the carb ...but bear in mind that all these .40-.40 glow engines could run on just 5% nitro, be it OS, ASP, MVVS, Webra, ENYA or Rossi.
It is totally a waste of money to use more nitro. A good glow plug for all these engines is either an Enya 3 or OS 8 plug.
Props could be anything from a small 9x6 to a 13x4, and anything between..We are nowadays running the OS .46 in Q-500 pylon racing planes here in Sweden (earlier only .40 engines) and a .46 OS turns a 10x6 prop (RAM or Graupner G-Sonic which are the best 10x6 props) at around 15000rpm using 80/20 fuel.

2W0EPI

HI Brutus,

I now have my F46 HS needle valve set at two turns out and I'm idling at around 2500 rpm, adjusting the idle mixture screw did the trick. Engine running smooth now, so yeah thanks for putting me straight, I have a great deal more confidence in Force engines now.

I couldn't resist, I bought a Force 52 with canted needle and purple head, not tried it yet but it's a lovely looking engine, very pleased.

1967brutus

Glad to have been of help. Have fun with it, and mind you I have no idea whether it is allready broken in but given how you struggled with the settings, I would be inclined to think it is not yet. So take it easy on the full throttle runs until the engine has a few litres through it.