I'm just wondering how much exhaust smake should be visible behind the plane in flight when the engine is set up correctly? I'm new to glow engines and have set mine up as per the manual (300 rpm drop at full throttle). I can see exhaust smoke on the ground when I accellerate and/or run it at full throttle, but it's not always visible in flight. Is this OK? Sorry for the newbie question, I'm just scared of cooking my engine.
Posts: 412
Joined: 10/16/2002 From: East Haven,
CT, USA Status: offline
When you tune the needle valve use a tach. Peak it then richen it up 300 RPM. I use Morgan Fuels Omega 10 and 15% The ring in the OS 160 likes castor oil.
i am planning on putting a 1.60 in my Ultrarc Katana. the tank is on the cg and I am going to be running a macs pipe and header. My question is what kind of numbers can i expect at sea levelwith an apc 18x6w running 15% and also should i buy a new carb? i'll be running a cline regulator and was wondering if the stock carb is ok or if i should go with a perry. please let me know.
Guys, I need a little advise. I have been playing with my two OS 1.60's all summer and I just can't get the rpm's that you guys are. Here's the set ups-
vp 30 pumps Bisson Pitts mufflers #8 plugs Morgan 5% with 18% oil (2-3% castor, can't remember) APC 18 x 6w props Large OS bubbless clunks One engine has med fuel tubing and the other has large 2200ft above sea level
The engine with the medium fuel tubing has turns about 7500 - 7400rpm depending on the day. The one with the large fuel tubing max's out around 6500 rpm. I have done everything (tubing, clunks, piston, ring, sleeve) to the lower one, except for bearings (which look fine), but the rpms stay the same!?!?!?! Any ideas?
Also, even my 7500rpm engine seems a little low. From what I have read it should be up around 8500rpm. Will going to 10% or 15% give make that much of a performance gain? Am I limited because of my altitude? I have this engine in my Ultra RC Giles and it barely hovers it. Most people are saying that this engine will yank the giles out of a hover, but mine sure won't. If I can't get this one running better that I think that I may just have to put a DL50 in it!
Posts: 216
Joined: 5/10/2006 From: Waldorf,
MD, USA Status: offline
GP
Don't believe the hype--you'll be lucky to get 7800 turning an 18x10. Mine was turning a mere 6000--sent it to OS and they sent me a new one--again, i'm doing good to get 7800. Be happy with 7500--it will last longer that way also. Try a 17x8 or a 16x8 or 10.
Mr DJ
< Message edited by Mr DJ -- 10/20/2007 2:02:11 AM >
Thanks for the info DJ. Perhaps it's time to do a big electric. That way I can keep it light, vibration free and just prop up to get the same power as the guys at sea level. I really like how light it flys though, I just need some punch out power.
Thanks Uncas. I wasn't sure if 2200ft would make that much diff. There seems to be a lot of people at sea level giving readings and alot at higher elevations, but nothing in between. I'll try to run some 10% before it snows.
Posts: 1
Joined: 10/17/2007 From: RUSTENBURGNorthwest, SOUTH AFRICA Status: offline
quote:
ORIGINAL: rvd
10% nitro, 20%oil syn/cas blend, O.S #8, 18X8 Zinger Bisson Pitts Muffler 7700rpm If i try to get more it starts to get crackly from detonation. [/q
Hi
I'm running on 5% nitro, 18% syn/cas blend, O.S #8, 18x8 Menz, 1300m above sea level, and I get 7950rpm. Take note that proper running in is also the key. O.S doesn't just brag that there engine need only a short breaking in period. In my case I do the following:
Start the motor at 1/2 throttle, advance to full throttle. let the motor run rich just below 6000 rpm (Rich). Remember the engine will heat up, but I keep touching the head for a second or so, and if it start to burn my fingers, I turn the mixture slightly richer. (Rather use a Thermometer and keep the head temp under 95 deg celcius).
IMPORTANT: If the engine is running very rich for too long you can cause more damage, because the piston and liner doesn't reach it's optimum working temperature.
A few people in the Ultra RC Katana thread have been very helpful in helping me to get my O.S. 1.60's running better. I thought that I would repost my findings here as it may really help someone. I have made the same modifications to my other 1.60 as well, but I haven't had the chance to run it up yet.
Original post from the Katana thread:
"Well, I made progress today!
I mounted my slowest 1.60 (was turning 6500-6700 max rpm) on the test stand and to my suprise it turned 7800 rpm right off the bat. The only difference between my test stand set up and the one in the plane is a T fitting and a fuel dot. I installed the T fitting on the stand and sure enough the rpm dropped back down. So that was problem number one. On my plane I'm going to run a third line into the tank just for the fuel dot, that shouldn't be an issue anymore.
I tried playing with the adjustment on the pump, but turning it up didn't help. As I turned it up I just had to turn the high speed needle in, which made it less precise. The engine also became easeir to flood and harder to start as I turned up the pumps pressure.
Next I put the stock muffler back on and the rpm went up about 50 rpm, but nothing to write home about. I then cut the tips off the ends of the Bisson pitts and mounted it back up. Instantly I gained about 500 rpm and after playing with the needles for awhile I was able to get a peak rpm of 8970!!! The exhaust note is really loud now though. I think that I'm going to order up a Slimline just to see if I can get the same kind of rpm with a lower exhaust note. It would also be nice to have those long exhaust stacks to keep the slime away from the plane. I'm also going to try a number 5 glow plug (tested with #8) as that is supposed to add some rpm too.
All of this was with 5% omega fuel and the 18x6w APC prop . I tried 15% omega but to my suprise it didn't add one rpm!?!?! I have read that others have experienced the same thing with the 1.60, but I thought that it would do something. The engine did feel hotter and smelled hotter too. I don't have a temp gauge, but I think that the higher nitro isn't worth the risk anyways.
All of this was done with an outside air temperature of about 2c, so I expect the numbers to be a little lower on a standard day. Over all I'm really happy with the results though. I went from 6500 rpm to 8900!!! That should make a difference.
Once again, thank you guys for all of the help! Greg"
Hey guys, I too have a 1.60 on an Ultra-RC Katana with a P-30 and Slimline pitts. I am using Morgan Omega 10% and I really do not have a problem as of yet as I have not even started it (the engine was bought slightly used i.e. just broken in) but my question is where to start with the high and low speed needle befor I use the tuning tips in post 116? The manual calls for I beleive 2.5 on the high and low to begin with but I seem to be reading that it needs to be leaned out a lot top and bottom. Should I just start at 2.5 for both of star out leaner? I have not touched the pump, it is set up as it came.
Also, what plug should I use? I have read an A8, but I think a while back someone recommended running a hotter plug. Yes or no and if yes what plug?
With the VP30 you will have to lean it WAY out from what the manual says. My high speed is around 1 to 1 1/4 turns out and I'm not sure where the low is - I just kept turning it in until it idled and transitioned right. It all depends on your pump pressure though. The more you trun up the pressure on the VP30 the more you will have to lean your needles (especially the high speed).
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All Forums >> Glow Engines, Gas Engines, Fuel & Mfg Support Forums >> Tachometer Readings >> RE: O.S 1.60FX Owners. Post your tach readings 
RE: O.S 1.60FX Owners. Post your tach readings - 
That way I can keep it light, vibration free and just prop up to get the same power as the guys at sea level. I really like how light it flys though, I just need some punch out power.
