Magnum .91 4-stroke starting problems
#1
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Magnum .91 4-stroke starting problems
I just purchased an airplane with a magnum .91 4-stroke, This is the first 4-stroke glow engine that i have owned. I have been working with engines for 12 years now ,and I learn something new every day. I have just been trying to flip start the plane, but when i do, it kicks back and seems to run in reverse. it has started in the right direction, but it would rather start in reverse. I know this is common with 2-strokes, but I have never known a 4-stroke could do this. Is this a valve clearance problem, or something else?Also, what is the valve clearance for this engine? Any Information would be appreciated. Thanks
#2
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RE: Magnum .91 4-stroke starting problems
Be careful hand starting it. A 4-stroke can backfire, especially when lean and throw the prop or do some damage to your hand. Not sure on the exact valve clearance for the Magnum but .002"-.004" would likely work.
#3
RE: Magnum .91 4-stroke starting problems
I love the engine but it is not a good engine to hand start. Dont know why, but it has a couple of threads and and the consensus is use a starter.
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RE: Magnum .91 4-stroke starting problems
The gap is .04 mm
IMHO I would suggest to use an electric starter by now, as you become more familiar with the engine and it gets some time running (about 1 full gallon), the you may experience the hand starting.
Most 4 strokes may back fire, sometimes because of lack of carburation (they seem to work fine in a wide range of carburation), so you should play a bit with the needles until you find that it is running at its best (quiet different with 2 strokers)
Best regards.
IMHO I would suggest to use an electric starter by now, as you become more familiar with the engine and it gets some time running (about 1 full gallon), the you may experience the hand starting.
Most 4 strokes may back fire, sometimes because of lack of carburation (they seem to work fine in a wide range of carburation), so you should play a bit with the needles until you find that it is running at its best (quiet different with 2 strokers)
Best regards.
#5
RE: Magnum .91 4-stroke starting problems
Sounds about right to me. Mine will run backwards for a few seconds then stop. I have hand flipped mine backwards and then it runs the correct direction. I gave up hand flipping for an electric starter. I like my fingers attached to my hand. It is worse with a new engine. After it breaks in some they are easier to start.
Dru.
Dru.
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RE: Magnum .91 4-stroke starting problems
Most motors start backwards because they are flooded. Prime the motor by putting your finger over the muffler and flipping it one or two should do it, and make sure the throttle is open fully, no startter battery on the plug yet. Move your throttle down to idle now.Then put the battery on, and pull the prop over counterclockwise till you feel it bump .make sure you have a good grip on the prop too. Now, just flip it counterclockwise, some like to go clockwise, but I don't. This is how I fire mine up. Good luck.