Hobbsy

My Feedback: (102)

DU, that engine is very similar looking to t my Zeus .61.

earlwb

Thanks for the info about the iron pistons in bigger model engines. I learn something new every day.

Dar Zeelon, maybe what Downunder stated about the breakin on his engine is the trick, it may be not really a ABC engine, it doesn't have a tapered cylinder wall like we expected. maybe no pinch. I'll have to clean my example and see how it feels after I get that super sticky anti-corrosion stuff out of it.

here is one thread that kmot started on the FIRE engine a while back:
http://www.rcuniverse.com/forum/m_70...tm.htm#9428946

earlwb

I thought I would clean out the anti-corrosion oil and see what the engine would do on my test stand.
But before I soaked the engine in gasoline to dissolve the oil residue, I thought I would take a few pics of the insides.

What was weird was with the anti-corrosion oil inside the engine, you could rotate the crankshaft 360 degrees and it didn't feel like it had the pinch at the top of the stroke like ABC engines usually have. But after getting the oil out and relubing the engine, it does have a pinch at the top. weird stuff that oil they used.  There is also a cutout in the the piston skirt for the bypass ports.

I'll break out my FAI fuel tomorrow and if time permits see if this engine will run or not,

it is interesting that there is a number engraved on the crankshaft.


The connecting rod still has the tooling marks on it. But it does look fairly robust. Unfortunately, the rod does not appear to have bronze bushings on it. So it'll need lots of castor oil then, 20% oil in the fuel.
\


The connecting rod still has the tooling marks on it as well.



And a pic of the Russian Glow Plug too.

Kmot

My Feedback: (24)

Earl, are you going to video the engine run?

earlwb

If it actually runs, yes I will.

earlwb

I test ran the Raduga 10cc engine on my test bench today. It fired up right away which was nice. But the low speed needle doesn't adjust or change anything. I screwed it all the way in to where the throttle barrel jammed up, and it didn't do anything to lean out the low end. So the OEM Raduga carb works Ok at about 1/2 throttle and up, but you'll have to dead stick it everytime for a landing though. So I would assume the Raduga engines are hit and miss on whether you get a decent carb or not. Considering how the carb fits, I wonder if the engines were primarily control line first and RC was a secondary minor option.

I didn't really try to run it hard yet as it has only had about two tanks of fuel through it. I used FAI glow fuel, 80% methanol with 20% castor oil, no nitromethane. After running it real super rich for a while to get the castor oil into the engine real good, I leaned it out some, to near the two cycle break point. Since this is a ABC design and it has a tight pinch at the top of the piston to cylinder fit, the break in ought to be more like a ABC engine breakin. When I tached it, it was turning a 12x6 APC prop at a little over 10,000 rpms. It was rapidly getting dark, so I tried to get a video of the tach readings, but the tach doesn't work when it gets too dark. Then I forgot about the fuel tank, and it ran out of fuel, so I called it quits for the night.

But 10,000 RPMs for a 12x6 prop doesn't seem all that great at the moment. I'll have to fire up another engine for comparison to see if there is any differences. The APC prop tends to load down the engines more than the other props do. Plus I want to try a few other props of different sizes and pitch too.

The OEM Raduga carb mounts on the engine at a tilted angle with the main needle valve angled forward towards the prop. They have a slight angle cutout in the muffler mounting ear to the barrel stop screw/idle stop screw on the carb. Now since the OEm carb's low speed idle mixture needle is essentially useless, and I don't see anything obvious to fix it, that means it needs a replacement. So since the carb looked like a OS carb copy, I dug through my parts boxes and found a old OS 7B carb. It fits perfectly into the crankcase intake hole. But the barrel stop screw is angled back farther, so I either have to live with a rather severely angled forward main needle valve, or I need to machine off a little of the muffler mounting tab on the engine's crankcase. Anyway, I assume most all of the 7 series OS carbs would likely fit OK. The other option is to go with a Perry carb too. As they have carbs that would fit just fine on the engine too. But since the engine uses a pinch bolt, the plastic body of the Perry carb might pose a problem over time, as you can't tighten up the pinch bolt as much.

You know in hind sight, somone may have messed around with the needle valves and screwed them in too tight. That results in the spray bar tube being belled out slightly. Thus the needle valve settings get screwed up. I did notice when I was checking out the carb, that the main needle had been screwed all the way in tightly. it took some effort to get it to turn so I could unscrew it a few turns to start the engine.

The Raduga 10cc engine's first bench run, with it running extra rich at about 6,000 rpms.



Mounting the OEM Raduga carb on the engine, sorta sucks with the extreme tilt or offset on the carb to clear the muffler mounting ear.



A OS 7B carb has a even more severe tilt or angle to it, in order to clear the muffler mounting ear. But it still clear the propeller though. But the fingers are getting mighty close to the prop still. Plus the throttle arm angle is rather off too much and it is harder to turn the throttle arm with so much of a angle on it in relation to the servo's pushrod.


I assume that most any of the OS 7 series carb would likely fit OK, once you deal with the muffler mounting tab, if you have to.



Short video of running the engine, too dark for the tachometer, and I forgot about the fuel tank.
[youtube]http://www.youtube.com/watch?v=JUjz1fsoh6M[/youtube]

earlwb

I machined the muffler mounting ear down a little to clear the barrel stop screw on the carbs. Now the OS carb and the OEM carb will fit just fine without having to be tilted at a angle so the barrel top screw will clear the engine. Later today, I'll bench run the engine again.

Kmot

My Feedback: (24)

Video = Neat!

tiffitech

I do have a left over original paperwork for the R10RU. It was bypacked to an MDS40 that I've bought on ebay.
It is for an engine with the number 1205 from 05/30/1985. It is printed in kyrillic russian.

Is someone interested on this? I think I can send it for free in a letter...

Kind Regards,

Holm

Edit: Hmm, I want to correct this a little, not for free, I want a picture Postcard from your hometown back :-))

Regards,

Holm

tiffitech

earlwb has responded first, so he will get this paperwork from me.

Regards,

Holm

sarpet

more bad old russian engines and extremely noisy pipe.
6.5cc engine is my old pylon engine, very narrow effect area,only fai fuel,rossi6 plug and apc 8x8 9x7 prop 18000rpm.
i use perry pump and super tigre carburetor.

tiffitech

I do have two MDS .40 engines that I've got from Ebay. An older Blackhead that had an worn out bushing in the low end of the Conrod,
(made and inserted a new one, engine is fine now) and an even older with an Silverhead and a golden prop driver (that comes off every time you don't fit a prop on). This one had a bad Carb, the difference to the Blackhead is, that the low end "needle" (actually a bush) is going over the Spraybar if you
get to the idle position, that from the Blackhead is going in the center of the Spraybar and is more to be called a needle.
It was impossible to get a reliable idle on this Silverhead engine that was made in 1985, even if totally closed the idle was much to fat
Both engines are ABC.
I've fitted an .60 Webra Carb on it which is functioning well but I have to turn out the HS nedle full 6 turns to get the engine run right.
It seems that it needs further investigation on this.
On The Crankcase from the Silverhead is the Label "MDC 6,5KU" (in cyrillic letters), the Blackhead "MDS 40".

Kind Regards,

Holm

maxtenet

I have many of the engines mentioned here as I am a fanatic. None of the ones I have seen pictured are the Raduga line. The MAC are non export MDS engines. With an oval on the side instead of MDS they are the east german models. The Zeus (nice engines)are a different company and the Stas (very under-rated)is another manufacturer. The actual Raduga engines are extremely crude ugly engines and shake like a paint mixer even though powerful. If I get time I may get 'em out of the attic and send photos.

Max

earlwb

maxtenet, yes please do, I am curious about them. So you say the 10cc engine I have in the first post is really a non-export MDS engine from that era?

I ran across a pic of a 1978 Raduga 7cc engine. it doesn't look all that crude from the pic.



The Cyclon 10cc F2B engine looks most fascinating too. It looks like they took a crossflow design engine to its ultimate conclusion.
The baffle plate on the piston is radically curved going into a slotted hemi-style head. the backplate has a curved slot to match the piston skirt.

downunder

You're the only person I know of that's even heard of them before although [link=http://carlsonengineimports.net/products/russian.shtml]Carlson Imports[/link] lists them. Below are the two versions I've got. The SE was the first (new from Ebay) because I thought it could make a reasonable CL engine but when I looked inside I was horrified because there's a huge void in the crankcase casting directly under the rear of the crankshaft bush so I've never dared to run it and swore I'd never get another. Then later (also on Ebay) I found the RE version so I figured what the heck, I like RE engines and it was advertised as the extremely rare RE CL engine.

In reference to that Cyclon (oh yeah, I'd like to have one of them!), the second photo shows the piston baffle on my Stalker 61RE which is similar to the Cyclon.

Konrad

What year (time frame) is that engine from? My FAI F3D Pylon engines from the late 80's (1987) would not come on pipe until I was over 18K rpm This took approximately an 8 x 7,8 prop (reworked props). Once one hit 18K+ rpm and a warmed up pipe the engine jumps almost instantly to 25K rpm. This is with pipe pressure only and no carb restriction (ALA Nelson). An 8ish x 8ish prop tuned at 27 to 28K on the ground is a thing of beauty to behold! [X(] I think 1996 saw the death of the rear intake F3D pylon engine. All modern FAI F3D Pylon engine are now front rotor, like your engine.
Some of my later FAI F3D engine were pulling into the 30K+ rpm band still rear intake. The new FAI F3D rules have us using a muffler on the end of the pipe.

earlwb

Some more pics I found of the Cyclon 10cc engine for F2B competition. these are from someone in Russia that was selling the engines. They did plan it out pretty good. even the fuel tank location in a model plane was considered. The curved baffle on the piston and the squish band head instead of the typical wedge combustion chamber shape for a baffle engine are fascinating. The 300 gram weight is really interesting. As that means the engine weighs less than most all of the 36 size 2 stroke engines out there. Even if you put a carb on it, it would weigh about the same as a typical 36 two stroke engine. Scary huh? You could bolt this onto a 25 size plane for lots of extra power. But then maybe not, I noticed that the RPMs on the ground are stated to be 8,000, thus I assume they intended the engine to turn a large prop then. But maybe it was a misprint or error about the 8,000 rpms. Maybe they meant 18,000 or something.

airraptor

My Feedback: (66)

for a CL engine that rpm may be correct. also looking at the port timing it looks to be low and small ports which means low rpm and torque. do you want to sell this engine?

earlwb

I wouldnot mind owning one myself. I just happened across the engine pics at a website, and I didn't know Cyclon had a 10cc engine out. I had thought that the cyclon engines were smaller, mostly 2.5cc.

downunder

That 8000 rev figure would be their suggested release revs (ground revs) using a suitable sized prop (~13x5?) to get a 4-2-4 run in the air and would almost certainly be 4 stroking. The peak HP shown (2.5HP) would be at far higher revs. The port timings have me curious though with that 10 degree differences and I'm guessing there's probably two options available, one with lower timing and another with the higher timings. This is similar to what Stalker offer where they have what they call a 2-2 timed engine, meaning basically that it's timed to hold a set speed either 4 stroking or 2 stroking, or a 4-2-4 timed engine. If you look closely at the Cyclon head button you can see a notch for a locating pin, somewhat necessary to make sure the piston baffle fits into the slot .

tiffitech

Hi guys,
I've got the same engine as earlwb today, an R10RU from 02/1986 N0 0720 and with the same unusable carb fitted.
Earl, it isn't really to see on your photos, is the low end "Needle" a bush going over the jet with the HS Needle?
I'm not tried to start this motor jet, cleaned it up only today and found a problem. The piston pin sat firmly in
the conrod and rotated in the piston. The engine wasn't new, it seems that the previous owner has overheated the top
end bearing, I've had to smooth the piston pin! Pleae check this on your engine. Maybe I should make a new piston pin...

For the carb: I'll try to make a new low end needle. The symmetrical slit in the jet (with the High end needle) has a bore in
the center, and the bush isn't going over this bore before the jet reaches the ground in the bush.
I'm shure this carb is heavy to fat on the low end since this bush isn't proper metering the fuel this way. I've had the same
type of carb in a old MDS .40 lately and this thing doesn't worked properly. I'ts impossible to set the low end lean eanough
since the jet is reaching the end of the bush before the bush is closing that fuel hole in the jet.. (sorry, I have problems to
express what I mean..)
Later versions of this carb have a needle going into the jet, closing the hole from the inside. This version worked for me.

How is the OS carb functioning bush over the jet or a needle into the jet?

BTW: Earl, I've got the same paperwork that I've sent to you again today :-)

Kind Regards,

Holm

earlwb

I'll look at the carb off of mine this evening and see if it has those problems or something else. But it sounds very likely. As you turn in the low speed needle it goes in far enough to jam against the main needle in the carb and stop the throttle barrel from closing.

My engine was new and liberally coated on the inside with some kind of a really sticky anti-corrosion substance. I had to soak it in a container of gasoline overnight to get the stuff out. Even then it stuck in places. After getting the sticky stuff out it was fairly loose and I could feel the pinch near TDC as I rotated the crankshaft..

it would not surprise me if someone didn't clean out the engine good first and or didn't break it in well at the start for the wrist pin to be stuck to the piston or connecting rod. But it could have been from the factory that way too. Hard to say on a used one. I more or less followed the Russian instructions and ran the engine slobbering rich for about 1 tank of fuel on the test bench. Then I leaned it out some and ran it harder like you would do with a ABC engine. But it was still on the rich side though. After about three fuel tanks I checked its peak RPMs for short periods and backed it off for a while, and then repeated the sequence. it seems to be working out OK.

Motorboy

In case the wrist pin is without teflon or bronze pad in the ends of the wrist pin or the wrist pin is secured with lock ring in the piston. The the wrist pin can be fastened (press fit) to piston or connecting rod to prevent galling in the sleeve.

earlwb

Ok, I looked at my 10cc engine's carb and I discovered that the idle needle is too short to cover the spraybar orifice. What happens is as you try to screw in the idle needle, it bottoms out in the end or tip of the spraybar. In the second pic you can see where if you screw in the needle, you cannot cover or block off the orifice in the spraybar any farther than what I show in the second pic. In the second pic the idle needle is the outer tube surrounding the right end of the spraybar. You can see the slotted orifice in the spraybar in the two pics.

it needs about 1mm to 2mm more depth to cover the orifice. So to correct the problem, one either makes a new idle needle that is longer, or you carefully drill the hole a little deeper on the inside of the idle needle, or you shorten the spraybar a little bit on the end.

But they don't make it easy to get the idle needle out. Apparently they pinged the threads on the outside to prevent the needle from unscrewing and falling out while the engine is running. So as you try to unscrew it, it stops on the outer edge of the threads. I tried to force it out, but one of the edges of the brass needle snapped off, So now I only have 1/2 of slot to screw the needle in and out with.
I think by simply removing the idle needle, and finding a drill bit of the correct size to fit inside, you can drill the inside hole about 1mm to 2mm deeper, and it should solve the problem. It looks like one needs to carefully drill the needle while it is inside the throttle barrel without removing it.

Oh yeah, the OS 7B carb is the same design. It has the same type of idle needle, but it extends a little deeper allowing one to cover or block off the spray's orifice better. The idle needle tube is a more thin brass tube as well, so it flows a tiny bit better than the OEM carb would allow.

tiffitech

That's exactly what I meant.

No earl. You cant drill it deeper an you maked the same fault with the low end needle as I, sanpping the half of the screw( Happened on the .40 Size Carb
for me, maybe it is the same, have to check this) But hat can be repaired.
You have to remove the carb barrel first, that you can unscrew the needle to the INSIDE. You will see, that this needle is a comlex thing with a groove
to hold an O-Ring. That groove is what prevents the bore from drilling out deeper.
You can snap of the second lonely half of the scre and make a new slit with a saw. BTDT.

The only way to make the carb functioning is to shorten the the spraybar in a drill press. What is the V-Slit AFTER the round hole good for in that orifice?
It's good for nothing. The fuel already comes as fat stream out of that hole, so maybe shortening the spraybar is the way to go. I've done that and payed with some solder on the spraybar but the carb was still not functioning well in the idle range.

How is the orifice looking on the OS carb?
I've mounted an .60 Webra carb to the MDS40, had to machine down the carb shaft to 12mm.

Regards,

Holm

Update: I have shortened the Spray bar on this carb now so that the LLS needle can go over the hole in the spraybar and can cover most of the orifice when
screwed fully in, but I've seen that there are lots of clearance between the spray bar tube and the LS needle (in my eyes) so I think that there would be still to much fuel going trough the gap between the needles. I'll test the engine later today.

Holm