Need help with engine - RC Groups
Thread Tools
Sep 08, 2006, 09:54 PM
Registered User

Need help with engine

New to the sport (very new to the sport, first plane, first engine). I have a O.S. 25 FX engine on a great planes piper cub. I have gotten to the point of testing my engine. Is it normal for the engine to spray(mist) fuel out of the muffler? I have read where people say it is normal for the engine to drip oil, but this is a spray(mist)? Also I built the model with the engine inverted, but I seem to have a difficult time starting the engine while it is inverted. I have since taken the engine off the plane to test and break it in attached to a vice. Engine starts on first try while upright, am I going to have trouble with the engine if I try to install it in my plane inverted? Any advice or suggestions would be appreciated. THANK YOU
Sign up now
to remove ads between posts
Sep 08, 2006, 10:08 PM
Suspended Account
Let me start by asking; how is it attacked to the vice? This could be a deal breaker if it is attached in such a way that the case is distorted.
Sep 08, 2006, 10:14 PM
Registered User
The engine is still attached to the motor mount, I drilled four holes in a piece of wood attached the motor mount to the wood and tightned the wood in the vice.
Sep 08, 2006, 11:59 PM
Registered User
No problem there if you clamped the wood piece.

While in the vice, have you adjusted the engine for optimum performance ?

Methodology described in sticky in this section. Follow those instructions to the letter, and then try again assembled in your cub.
Last edited by indoruwet; Sep 09, 2006 at 07:33 AM.
Sep 09, 2006, 03:01 AM
Registered User
It's not unusual for engines to be trickier to start inverted usually because it's generally easier to flood them and "put the glow out". You'll probably find it's o.k. once you have it tuned and run in properly. If not the solution is pretty simple. Turn the plane over and start it with the engine upright. It will run fine inverted, it's only starting that's the problem.

It's normal for there to be visible exhaust containing unburnt oil coming out of the muffler when the engine is running.

Sep 09, 2006, 02:22 PM
It's 5 O'clock Somewhere
RumRunner_1492's Avatar
Since you are new to the sport you should find a local club or someone that has some experience to help you out. The worst thing you could do is figure out how to get the engine running and then crash your plane on the first flight.
Sep 09, 2006, 02:36 PM
Registered User
If this the RumRunner in Dayton Ohio (that i'm thinking of), your advice seems sound if it came from a person who at least tried to build and fly a real plane. But coming from a boy like your self the best advice I can give you is Keep on flying your aero ace air pig (what ever that thing is you took to the air field yesterday, and got laughed at). But anyways I might do what you say look up a club and get some help, and when I do get my bird in the air, I'll save you a seat (in the back) and show you what a real plane is about. I hope the winds stay calm today so you can fly your pig. B

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Need help with an old engine Joe Ford Engines 62 Feb 19, 2012 10:54 PM
Alert Need help with Gas powered engine lozano415 Engines 5 Jan 16, 2005 06:41 AM
Need help with lawnmower engine trouble. mrebman Life, The Universe, and Politics 14 Aug 07, 2004 03:55 PM