Technopower 5B radial discussion.
11-11-2020 | 11:39 AM
#27
William Robison
Community Moderator
Certified
From: Mary Esther, Florida, FL, USA
Eugene:
You are in the right size range for the Technopower 5B engine, the best ones you have listed would most likely be either the WACo or the Stearman. The short nose moment usually needs nose weight with the usual engines, the TP radial has the weight. The power goes along with the size of the planes you are considering. One of the more modern planes might well be too nose heavy without weight in the tail, and then the entire plane could become too heavy to fly well. On the older biplanes they look, sound, and fly very well.
I suppose I do know a fair bit about them, but a lot of it is from failure analysis.
Overheating is a fact of life with the Technopower engines, get used to it. You can not leave them running on the ground very long. Start it, do your ground checks, taxi out and take off. No problem that way.
Yours with the cast rocker boxes is a great improvement over the originals, but you still have the steel sleeves inside the aluminum finned muffs. The latest version has one piece cylinders, all aluminum with chromed bores. Much better.
Your engine also has a cast master con rod. This is the last weak point that has been addressed. With the cast rod you are almost guaranteed a problem if you let the engine run over 6000 rpm. The latest production uses a billet rod, the latest ones will run at 8000 rpm happily. As a result, the latest engines also are a LOT more powerful than the older ones.
So what can you do? Marc Linville has stopped production of all the five cylinder engines, but you might be able to talk him into doing a one-off billet rod for your engine. That would be the greatest improvement possible. I don';t have the specification sheets handy, but as I remember one of the sevens has the same cylinder bore yours does, if you can get five AAC cylinder sets for your engine along with the billet rod you will have a great engine. All the new cylinders are also anodized black, an improvement in looks too. I'll warn you in advance, it is not an engine for an amateur to take apart and reassemble. Might be able to talk Marc into doing the upgrade for you. Remember too, the cost will not be pocket change.
If all this upgrade talk scares you I'm sorry. It is still an excellent engine just the way you have it, don't be afraid to fly it and enjoy it in the stock condition. Just be aware of the limitations and it will give you good service.
One further thing - keep the oil around 10%, 15% is too much after break-in. A synthetic/castor blend is fine. Minimum nitro, 5% is plenty.
Bill.
Community Moderator
Certified
From: Mary Esther, Florida, FL, USA
Eugene:
You are in the right size range for the Technopower 5B engine, the best ones you have listed would most likely be either the WACo or the Stearman. The short nose moment usually needs nose weight with the usual engines, the TP radial has the weight. The power goes along with the size of the planes you are considering. One of the more modern planes might well be too nose heavy without weight in the tail, and then the entire plane could become too heavy to fly well. On the older biplanes they look, sound, and fly very well.
I suppose I do know a fair bit about them, but a lot of it is from failure analysis.
Overheating is a fact of life with the Technopower engines, get used to it. You can not leave them running on the ground very long. Start it, do your ground checks, taxi out and take off. No problem that way.
Yours with the cast rocker boxes is a great improvement over the originals, but you still have the steel sleeves inside the aluminum finned muffs. The latest version has one piece cylinders, all aluminum with chromed bores. Much better.
Your engine also has a cast master con rod. This is the last weak point that has been addressed. With the cast rod you are almost guaranteed a problem if you let the engine run over 6000 rpm. The latest production uses a billet rod, the latest ones will run at 8000 rpm happily. As a result, the latest engines also are a LOT more powerful than the older ones.
So what can you do? Marc Linville has stopped production of all the five cylinder engines, but you might be able to talk him into doing a one-off billet rod for your engine. That would be the greatest improvement possible. I don';t have the specification sheets handy, but as I remember one of the sevens has the same cylinder bore yours does, if you can get five AAC cylinder sets for your engine along with the billet rod you will have a great engine. All the new cylinders are also anodized black, an improvement in looks too. I'll warn you in advance, it is not an engine for an amateur to take apart and reassemble. Might be able to talk Marc into doing the upgrade for you. Remember too, the cost will not be pocket change.
If all this upgrade talk scares you I'm sorry. It is still an excellent engine just the way you have it, don't be afraid to fly it and enjoy it in the stock condition. Just be aware of the limitations and it will give you good service.
One further thing - keep the oil around 10%, 15% is too much after break-in. A synthetic/castor blend is fine. Minimum nitro, 5% is plenty.
Bill.
Hello Bill. I know it's been 15yrs since you contributed to this thread but I happen to come across across a TP 5 cylinder engine. I'm assuming this one incorporates all the headaches you mentioned. Also, mine does not have an engine mount. Can you point me in any direction in order to ameliorate the plastic rocker covers, cylinder sleeve and con rod issues you mentioned?
Thank you in advance for any and all help,
Robb
