iflircaircraft

I'm building (assembling) a P51 Mustang. This is the first time I'll be installing an engine inverted (OS95v 4 Stroke). I have 20% nitro 18% synthetic fuel. Are there any tips to setting up an inverted installation?
Fuel tank level,fuel lines, etc


Tom

Rv7garage

My Feedback: (10)

You might get better results by posting your question here-

http://www.rcuniverse.com/forum/forumid_114/tt.htm


Woot! 1000 posts! [&:]

jester_s1

As long as the tank centerline is close to even with the carb spraybar, you're good. Being a touch low is helpful to prevent fuel siphoning, which is the only issue you'll likely encounter with it. As for tuning and such, there is no difference once the engine is running.

jetmech05

You know you don't have to run the more expensive high nitro content fuel in a 4 stroker,,,,I ran a 180 inverted with a programmable on board glow driver...had it come on at 1/4 throttle or less on 15% nitro ...never had a dead stick

Luft-Gangster

Once running they are fine. Its starting them inverted that can cause problems. The engine can flood easily and if using an electric starter it can bend things like push rods, rocker arms, etc. Been there, done that. Easy to repair with new replacement parts, if youre handy.
My solution: Make a cradle to hold the airplane inverted for starting ( engine upright ) . Once started, lift out of the cradle, sit on wheels, adjust needle and fly.

j.duncker

My Feedback: (2)

Re the hydraulic lock on start up problem. I think if you hand crank it 2 or 3 time with out the glow connected then that allows you to feel for the lock and if OK then glow on and start as usual.

I found that my OS 120 Surpass needed the electric starter for the first start of the day but could be hand started easily aftwards.

Turning large models over with the engine running needs to be done with great care. I have seen a couple of incidents over the years resulting in hospital visits for stitches.

Stick 40

nice plane and engine.

I would think about using a on-board glow system, you would very few if any dead sticks.

I inverted a couple of Saito engines and one I put a on board glow and it seemed to be less trouble.

maukaonyx

I have an OS91 Surpass II (no pump) in my Intruder, inverted, and it runs great. I use an electric starter to get her going, and I start her up with her sitting on her LG on the ground. All of my 4 strokes run on 15% Omega and seem real happy, from OS 52 to OS 120, and some Saito 82 and YS 63 thrown in there too. Jon

speedracerntrixie

My Feedback: (29)

You may want to consider setting up the engine inverted on a test stand and become familiar with it in this position before going to the airplane. Set the tank at the same level as it would be in the airplane. This will allow you to get it fine tuned in that position and learn it's starting chararcteristics.

airraptor

My Feedback: (66)

all the guys at our field run the OS 95V in the WM mustangs and run them inverted. No real problems. the main thing is to make sure the throttle is completly shut and the throttle trim is all the way down. DO THIS to prevent flooding the engine when fueling. If you use a electric pump or crank fast on the hand pumps the air in the tank can not get out fast enough thats displaced by the fuel. the tank is slightly pressurized and you can/will force fuel thru the carb if is just off idle or open any bit at all. this will cause the fuel to puddle in the intake tube if the valve is closed or to fill the chamber if the valve is open.

make sure throttle is closed, turn by hand couple of times by hand and use a OS F plug. All the guys dont run on board plug heat either.

the best prop for the 95V on the WM mustangs is the 12x10 for bigger planes above 7 lbs the 13x9 APC is a great choice.