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Building Tips and technical articles. => 1/2 A building. => Topic started by: Joe Rice on April 08, 2011, 06:44:01 AM
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I built a couple of ARC Baby Clowns for a Norvel .049 that I purchased a couple of years ago. I noticed that my engine is the "AME" version and have heard that they will not run properly without a pressure system. Will the muffler pressure suffice?
Joe
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Joe,
That was true of the early ABN version, I'm not sure it's true of the REVLITE version. My Big Mig CL versions came with a muffler that has a pressure nipple. If yours did not, a prop that allows good venturi velocity should help. NORVELs have a large intake for power so they must be allowed to rev-up to maintain fuel draw.
George
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Joe,
That was true of the early ABN version, I'm not sure it's true of the REVLITE version. My Big Mig CL versions came with a muffler that has a pressure nipple. If yours did not, a prop that allows good venturi velocity should help. NORVELs have a large intake for power so they must be allowed to rev-up to maintain fuel draw.
George
George... mine has the muffler with pressure nipple and came with a clear plastic tank mount with integral radial mount. Seems as though I should be ok.
Joe
Joe
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Joe, you will definitely get better runs with muffler pressure on this engine than trying to run it without any pressure. Should be a good match for your clown. Sometimes those tank mounts are long enough to throw off the cg, on my Baby flite streak i had to add tail weight. Also there should be a diagram with the tank on how to fix the pickup for c/l or sometimes Norvel included a different pickup tube. Good luck, let us know how it does.
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Joe, you will definitely get better runs with muffler pressure on this engine than trying to run it without any pressure. Should be a good match for your clown. Sometimes those tank mounts are long enough to throw off the cg, on my Baby flite streak i had to add tail weight. Also there should be a diagram with the tank on how to fix the pickup for c/l or sometimes Norvel included a different pickup tube. Good luck, let us know how it does.
George... My engine will be beam mounted... I will not be using the plastic tank that came with the engine, but will use a metal tank set up like the big profile planes
Joe
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Last weekend, I tried to run a new Norvel AME on a Baby Flite Streak. Well , I won't sugarcoat it for you it wouldn't work. The second I let the plane go, it would almost stall. Then the run was all over the map going lean then rich and back again. I put the engine on bladder and problem solved. I was wondering if the choke area could be shrunk down with some tubing. If the screen was removed I was going to try and find tubing to choke it down. I was also going to try another option. I was going to take a broken APC prop, cut it apart as to only have the hub. I was going to drill the prop hole out then tap the hole to 1/4-32 which is what I believe the Tee Dee venturi is. Then cut sand shape the hub to fit into the case opening and hold it in with a bit of JB weld. I was hoping I could then screw in the Cox Tee Dee set up with a Kirn needle and this would solve the problem. I do have currently one AME ABN engine running backplate pressure to the uniflow vent on the tank and this works well. You should try to email klondike17@juno.com I think his name is Andrew. Ask for a pressure type backplate as this would be the simplest solution. He now handles the line of the former Norvel's now known as N/V engines. Ken
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George... My engine will be beam mounted... I will not be using the plastic tank that came with the engine, but will use a metal tank set up like the big profile planes
Joe
You can still use muffler pressure on the metal tank. Just run tubing from the muffler nipple to the fill line on the tank and put a plug on the tank overflow.
BTW, some of those plastic tanks were setup with the pickup tube on the bottom for RC use. I had to bend the tubing on my first one. The second one came with two tubes so you could select.
George
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Last weekend, I tried to run a new Norvel AME on a Baby Flite Streak. Well , I won't sugarcoat it for you it wouldn't work. The second I let the plane go, it would almost stall. Then the run was all over the map going lean then rich and back again. I put the engine on bladder and problem solved. I was wondering if the choke area could be shrunk down with some tubing. If the screen was removed I was going to try and find tubing to choke it down. I was also going to try another option. I was going to take a broken APC prop, cut it apart as to only have the hub. I was going to drill the prop hole out then tap the hole to 1/4-32 which is what I believe the Tee Dee venturi is. Then cut sand shape the hub to fit into the case opening and hold it in with a bit of JB weld. I was hoping I could then screw in the Cox Tee Dee set up with a Kirn needle and this would solve the problem. I do have currently one AME ABN engine running backplate pressure to the uniflow vent on the tank and this works well. You should try to email klondike17@juno.com I think his name is Andrew. Ask for a pressure type backplate as this would be the simplest solution. He now handles the line of the former Norvel's now known as N/V engines. Ken
Thanks, Ken