boss351

My Feedback: (6)

Out of curiosity, how many of you are successfully running their Rossi (mine is an R45) mounted inverted? I have been struggling to get it to transition and even start easily inverted for a month. Through some advice from Dar yesterday I sat the plane upside down on a stand and hey-presto, it starts and runs like a champ. I can see making a cradle to take to the field to get this thing started upside down is a possibility but for now I just remounted the engine right side up.

If you are running yours upside down will you tell me your setup, plug used, priming and starting procedure, centerline level of the tank vs carb, fuel you are using, and prop size/type.

Thanks!

Adam

downunder

I have mine mounted at about a 45 degree angle down so the muffler is centred underneath the fuselage so I guess that could be considered inverted. On a cold start (first for the day) what I do is stand the model on one wing tip (this puts the engine upright as yours would be when the model is inverted) and give it a few primes by turning the prop. Then I flick the prop to spread the fuel through the cylinder and make sure it has that "just wet" feel. Put it back on the wheels, hook up the plug battery, give it a few seconds to heat the plug fully then give it one flick. The ONLY secret to it is knowing the exact prime your engine needs and how it should be spread through the cylinder.

Inverted engines need to have the idle mix set very carefully, it should be just barely on the rich side..in other words only a very small rise in revs when you do the pinch test after it's been idling for a while. The type of fuel and prop used shouldn't make any difference but I'm using zero nitro and 20% all castor. The prop is an 11x6 Master but I couldn't even guess what sort of plug I'm using because it's been in there for so long except I can guarantee it's not an OS

boss351

My Feedback: (6)

Downunder,

by coincidence that was exactly how my engine was mounted also. What I plan on doing since the engine is fairly new still is wait until a couple of gallons of fuel have run through it (the ay these drink shouldn't be too long then I will try the almost inverted mount again.

So, even with a long idle you are able to make smooth fast transitions up to full whack?

Cheers,

Adam

downunder

I don't have any problems even though I run it VERY rich at full throttle. In level flight I run it at a 4 stroke setting and it breaks into a 2 stroke in manoeuvres.

Razor-RCU

My Feedback: (50)

Mine ran great inverted- don't wanna guess on the plug though... I ran 5%, 9x8 apc, carb was a "hair" below center on tankline, low end was VERY rich when I got the engine-

TNRabbit

I found that 0-5% nitro with a high oil contect (i.e., Morgan Omega 5%) works fantastic with an Enya #3 glow plug (pricey, but EXCELLENT plug). Also, an O.S. #1 plug works well. Basically, you need a hot plug with the low nitro content. Man, this engine HOWLS! I've seen nothing short of a Jett ($$$ cha-CHING!) that comes close to it in power and sheer rpm's.

TNRabbit

Last post--OOPS--The engine I was talking about was the Rossi .45 w/mini-pipe. A screamer! The guys at the field were really impressed.

boss351

My Feedback: (6)

I have an Enya #3 plug on its way to me, I am using the OS #8 right now and Power Master 5%Nitro, 18% blend fuel. I am just about done on the present gallon and will try out the Omega next together with the Enya Plug, I want to get the engine mounted back inverted again as the pipe down the belly of the plane is just a slicker set up.

TNRabbit, what size prop are you using?

TNRabbit

I started with a 10 x 6 APC and it just SCREAMED!--enough oomph to pull my Four-Star 40 straight up at least 400 feet at a little over half throttle! I hadn't flown in three years to I decided to try an 12 x 4 APC, which slowed the speed down an little but gave more usable thrust. I think I'm going to settle on an 11 x 5 APC for the prop clearance and to get a little bit more speed. It was UNREAL with the 10 x 6!

I was having a he** of a time getting it to run during break-in and was just about to throw it in the trash when I decided to check the web; I found that if you take the carb apart and "hand turn" a small drill bit in the channel of the needle, it helps a little. also, start your low speed adjustment on about 1 turn out from full in and test turning it in about 1/8th turn at a time until you get it to transition right. After I switched to the Enya #3 plug and Omega 5% (I was using 15% for the first gallon) and took off the 11 x 7 wooden prop and installed the 10 x 6 APC, it became a different engine...an ANIMAL!

boss351

My Feedback: (6)

The first few flights I made with the R45 was with the 11x5, after using an OS 40LA with a 10x7 the jump in speed and power scared the ***p out of me. I put an 11x4 on for now until I more accustomed to the engine and plane. There is a sport prop, I think 12.25 x 3.75 or thereabouts that looks really interesting, I want to get a hold of one of them to try out also.

I switched to an MVVS carb that really helped with the managability of the transition and tuning (thanks Dar), I am really getting to like this little monster!

TNRabbit

I'd like to get this engine on a GP Patriot or Tigershark F-20 and put an APC 8 x 9 prop on it! Scary speed!

Hmmmm.....I'm beginning to believe that the whole "nitro" thing is a giant marketing ploy to make us spend our hard-earned cash on something that's unnecessary....

scooter j

The best way to start your rossi .45 while inverted is to simply place your finger over the end of the mini pipe while hitting the starter. The back pressure will force fuel into the carb and it will start instantly. I do this everytime and this engine starts great inverted. I have mine in a 6 pound Cermark Javelin 2. It really moves.