Tower 46 / Also OS ???
05-10-2003, 01:28 AM
#1
Thread Starter
Tower 46 / Also OS ???
Helping newbie with total Tower rig, Engine is a *Tower* 46. If not OK here just say so and ignore question.
Engine came with a performance type muffler. Acts very *tuned* more like a racer than a sport engine.
Engine will come *on* at the slightest needle off a 4-cycle. It is then too lean to adequately fly maneuvers.
If set richer, it stays too rich to take-off.
Have tried a number of plug/fuel/prop combinations. Nothing works well enough for reliable RC operation.
If feed line is pinched to lean out engine for TO then engine does very well until throttle is reduced to try some approaches, then again too rich. Besides can't taxi out with the pinch thing.
Cleaned and blowed the carbs, etc also.
Having done some CL speed work, plus RC sport racing using tuned pipes up to and including double pressure wave operations, I am very much into the belief that the muffler is at fault for this situation.
We plan to try to change to some other muffler shortly.
What do you think?
Engine came with a performance type muffler. Acts very *tuned* more like a racer than a sport engine.
Engine will come *on* at the slightest needle off a 4-cycle. It is then too lean to adequately fly maneuvers.
If set richer, it stays too rich to take-off.
Have tried a number of plug/fuel/prop combinations. Nothing works well enough for reliable RC operation.
If feed line is pinched to lean out engine for TO then engine does very well until throttle is reduced to try some approaches, then again too rich. Besides can't taxi out with the pinch thing.
Cleaned and blowed the carbs, etc also.
Having done some CL speed work, plus RC sport racing using tuned pipes up to and including double pressure wave operations, I am very much into the belief that the muffler is at fault for this situation.
We plan to try to change to some other muffler shortly.
What do you think?
05-12-2003, 01:44 PM
#2
My Feedback: (11)
Tower 46 / Also OS ???
Horace,
With the standard, stock muffler the engine should run very well.
If the engine is trending lean, try richening the idle mixture a lot, start at part throttle, advance to full and set the high-speed needle, and then retard the throttle and get the idle mixture and RPM adjusted.
The idle mixture can be set incorrectly at the factory and is one of the first places we look for operating problems.
With the standard, stock muffler the engine should run very well.
If the engine is trending lean, try richening the idle mixture a lot, start at part throttle, advance to full and set the high-speed needle, and then retard the throttle and get the idle mixture and RPM adjusted.
The idle mixture can be set incorrectly at the factory and is one of the first places we look for operating problems.
05-13-2003, 02:05 AM
#3
Thread Starter
Twr .46
Thanks for the reply. However all that had been done several times.
Today, young "Mike" came over and I had an older Asp muffler handy (a clone of old OS 40 FSR) That muffler was a perfect fit including bolt threads.
Fired 'er up and reset all the needles for a very nice little engine.
Mike has soloed out, so he went over to the field and made several flights. Everything was just fine, all A-OK. Engine performed very well.
From other reports, it seems the *performance* muffler may be a bit narrow in tolerance for this sport engine.
He's happy, I'm happy and you have some more case-history.
Today, young "Mike" came over and I had an older Asp muffler handy (a clone of old OS 40 FSR) That muffler was a perfect fit including bolt threads.
Fired 'er up and reset all the needles for a very nice little engine.
Mike has soloed out, so he went over to the field and made several flights. Everything was just fine, all A-OK. Engine performed very well.
From other reports, it seems the *performance* muffler may be a bit narrow in tolerance for this sport engine.
He's happy, I'm happy and you have some more case-history.
05-20-2003, 09:53 PM
#4
Tower 46 / Also OS ???
The Tower 46 I had showed similar problems. I found an OS #8 glo plug solved quite a few of the problems. The other problems you will have are:
Air leaks - silicone the backplate and carb
Will not shut down/air leak - leaking front bearing/seal Not much you can do with that except replace it with an after market sealed bearing.
Once the glo plug and air leaks were taken care of power with Byron 10% and an APC 11 x 7 was awsome. My SuperStar trainer had extreme vertical and would hover with an APC 11 x 5.
Air leaks - silicone the backplate and carb
Will not shut down/air leak - leaking front bearing/seal Not much you can do with that except replace it with an after market sealed bearing.
Once the glo plug and air leaks were taken care of power with Byron 10% and an APC 11 x 7 was awsome. My SuperStar trainer had extreme vertical and would hover with an APC 11 x 5.
