stunthanger.com
Engine basics => Four strokes only => Topic started by: Leo Mehl on June 24, 2011, 03:56:23 PM
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I was in the Hobby shop the other day and I noticed they had a Magnum 30 four stroke for sale so I said to myself "self I think that engine would fit right on a LA 25 motor mount" so I bought it. I had only a 1.,50 oz tank to run this engine so that and the engine both fit right on my Streak like they were made just for this plane. I took it out and flew it but the engine run was short and a strait tank that ran rich the first half and just right on the second half of the tank so when I got home I built a bigger tank that was uniflow. Now I head someplace that four strokes did not run well on uniflow so I hooked it up for presure, I got a real iratic engine run so I pulled the tubing off and ran it on uniflow. WOW it ran the same from beginning to end. I was using a 10x4 APC on it so I changed it to a 10x5 and slowed it down with the carburater. SWEAT. Its a fun plane now and I actually had to add nose weight to it. Go figure, Did I mention this was an ARF flight streak. HB~> HB~> HB~> HH%% HH%% HH%%
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WOW it ran the same from beginning to end. HB~> HB~> HB~> HH%% HH%% HH%%
Welcome to the world of the 4 stroke stunt run.
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I actually began flying four strokes before they became popular. H^^
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Leo - my first four stroke setup was a Flite-Streak with an OS 20. It worked very well, flying on 52 foot, .012 lines.
Not knowing how little fuel the engine used, I made my first flight on a 3 1/2 ounce tank.
I was concerned and hoped that it would quit before sundown!
Although I have not flown the Magnum 30, when I bench tested one, I found that the power was not what I expected. It turned a prop just a tad slower than my OS Surpass 26. Your results may be different.
Bob Z.
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Leo - my first four stroke setup was a Flite-Streak with an OS 20. It worked very well, flying on 52 foot, .012 lines.
Not knowing how little fuel the engine used, I made my first flight on a 3 1/2 ounce tank.
I was concerned and hoped that it would quit before sundown!
Although I have not flown the Magnum 30, when I bench tested one, I found that the power was not what I expected. It turned a prop just a tad slower than my OS Surpass 26. Your results may be different.
Bob Z.
This engine had no compression when I got it and after it was btoke in it has compression and seems to have plenty of power. I am going to put it in a Magician. It fits on same motor mount as the LA 25/ I have to use electric starter as it doesn't like to run right directiom when starting If you crank it backwards it will run backwards. It's definately a differnt animal. I am flying on`.15 x 60 foot lines HB~> HB~> :!
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This engine had no compression when I got it and after it was btoke in it has compression and seems to have plenty of power. I am going to put it in a Magician. It fits on same motor mount as the LA 25/ I have to use electric dtarter as it doesn't like to run right directiom when starting If you cranl it backwards it will run backwards. It's definately a differnt animal. I am fling on`.15 x 60 foot lines HB~> HB~> :!
Hi Leo,
Just to make sure, have you tried to turning it clock wise until you feel compression then turning the prop half way counter clock and give it a good prop swing clockwise?
This method has worked for me with just about any engine, including 2S. Never through compression.
If I choke too rich my 4S it will start backwards, but it starts correctly the second try.
Martin
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I have tried all the usual proceedures starting this engine but have given up and now use an electric finger. It runs the right direction every time I start it now.It seems to have plenty of power and it5 is a bll on a flight streak. #^ #^ #^ #^ #^ #^