OS .46 LA (Bad Engine?)
#26
ORIGINAL: microsprint9
opjose Date 12/15/2006 2:45:42 AM
Frankly I doubt it.
I put the LA .46 into a .30 plane and it does very well on that plane, including good verticals.
I've tach'd it to about 10.5K with an 10x5 prop sitting on the ground.
Not too sure about your tach readings, i'm getting 12000rpm with a 10x5 on a .40LA with 10% omega, i'm sure the .46 must have more power than the .40. My motor is stock with no carb alterations and the baffle is still in the muffler, motor has about 2 gallons thru it.
opjose Date 12/15/2006 2:45:42 AM
Frankly I doubt it.
I put the LA .46 into a .30 plane and it does very well on that plane, including good verticals.
I've tach'd it to about 10.5K with an 10x5 prop sitting on the ground.
Not too sure about your tach readings, i'm getting 12000rpm with a 10x5 on a .40LA with 10% omega, i'm sure the .46 must have more power than the .40. My motor is stock with no carb alterations and the baffle is still in the muffler, motor has about 2 gallons thru it.
I'm not going to run it this way in the air.
On my .30 plane I have plenty of power for it... just not enough for my .46 planes.
#27
ORIGINAL: Ed Cregger
As someone stated in this forum a few years ago, "The OS .40 LA is the best .25 I've ever owned". <G>
Ed Cregger
As someone stated in this forum a few years ago, "The OS .40 LA is the best .25 I've ever owned". <G>
Ed Cregger
As a .30 it's great, forgoing the low end richness. It fit just fine in a .32 mount space.
As a .46? It's a great .30....
#28
ORIGINAL: wcmorrison
All the foregoing is good stuff for you. None of the OS LA engines have ball bearings, they have sleeve bearings. The more expensive OS engines the OS 46AX or FX are ball bearing engines. As Ed Creggor said, go for a Thunder Tiger Pro which has ball bearings, cost less than the OS AX or FX and provides near same performance if not better performance. Do not rule out the Magnum engines either, they are also comparablae to OS AX and FX and also cost less too. You can also look at the Tower Hobbies 46 or the GMS 47, also comparable to OS AX and FX performance levels and cost less that the OS engines.
Frankly, there are a lot of good engines out there that cost less than an OS. There is no true mystic about OS except that they cost more.
All the foregoing is good stuff for you. None of the OS LA engines have ball bearings, they have sleeve bearings. The more expensive OS engines the OS 46AX or FX are ball bearing engines. As Ed Creggor said, go for a Thunder Tiger Pro which has ball bearings, cost less than the OS AX or FX and provides near same performance if not better performance. Do not rule out the Magnum engines either, they are also comparablae to OS AX and FX and also cost less too. You can also look at the Tower Hobbies 46 or the GMS 47, also comparable to OS AX and FX performance levels and cost less that the OS engines.
Frankly, there are a lot of good engines out there that cost less than an OS. There is no true mystic about OS except that they cost more.
Bench testing is a wonderful and informative thing...
The GMS .47 and the TH .46's have been GREAT for me, after they have had about 1-2 gallons run through them, whereas the LA practically ran fine on it's second tank.
#29

My Feedback: (212)
It depends on what it's used for, I have a LA46 on my Kadet Seniorita it hovers at 7/8 throttle running a little rich, (had a LA40 first it would only tailslide no hover)I would like more power but that means a heavier bb engine or a expensive small Hi Perf engine, a heavier engine would ruin the great flight characteristics of the plane, so for certain planes it's very good, 125 flights with no deadsticks so far and still runs as new or better, I allso have a Macs one piece muffler to reduce the weight by allmost 2 more OZs, if I were setting up my first trainer unless it's as light as a Seniorita I would go with more power than the LA46. my 2 cents
#30
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From: FrederickMD
I have an LA 46 that has seen service in 4 planes. Its currently pulling a restored Nexstar. The engine has always been easy to start and reliable. I found the key was not UNDER propping it. Sure it won't run a 10x4 at 14,000, but it will run an 11x5 at 11,000, which is more than enough to service the trainer its on. And it will idle at 2000 rpm with that same 11x5 prop. With a 12 oz tank at 1/4 throttle, I can probably keep the Nexstar in the air for 40 minutes.
Like any other engine, its only as good as its intended purpose.
Brad
Like any other engine, its only as good as its intended purpose.
Brad
#31
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ORIGINAL: bkdavy
I have an LA 46 that has seen service in 4 planes. Its currently pulling a restored Nexstar. The engine has always been easy to start and reliable. I found the key was not UNDER propping it. Sure it won't run a 10x4 at 14,000, but it will run an 11x5 at 11,000, which is more than enough to service the trainer its on. And it will idle at 2000 rpm with that same 11x5 prop. With a 12 oz tank at 1/4 throttle, I can probably keep the Nexstar in the air for 40 minutes.
Like any other engine, its only as good as its intended purpose.
Brad
I have an LA 46 that has seen service in 4 planes. Its currently pulling a restored Nexstar. The engine has always been easy to start and reliable. I found the key was not UNDER propping it. Sure it won't run a 10x4 at 14,000, but it will run an 11x5 at 11,000, which is more than enough to service the trainer its on. And it will idle at 2000 rpm with that same 11x5 prop. With a 12 oz tank at 1/4 throttle, I can probably keep the Nexstar in the air for 40 minutes.
Like any other engine, its only as good as its intended purpose.
Brad
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Which prop to use is more a function of the combination of engine/airplane. Sometimes a 10x5 adds that little extra sparkle that helps some trainers flying off of rough grass fields get airborne sooner. Other times and planes, for instance a Sig Senior Kadet with tons of wing area, the 11x5 might be a better choice, as you have pointed out. It is not a black or white situation. There are many variables to consider.
Ed Cregger
#32

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From: Dunnunda, AUSTRALIA
ORIGINAL: Zephirus79
He said "The non bearinged are not good at dependability (running adjustment wise)".
He said "The non bearinged are not good at dependability (running adjustment wise)".
An LA 46 puts out a claimed 1.2ps and the AX a claimed 1.65ps at peak power. That equates to the LA producing approximately 73% of the potential power of the AX if both were producing peak. No-one ordinarily operates them at that high an RPM in the power curve for sport flying, but the proportional reality IME is still somewhere around the LA producing approx ¾ of or 75% of the power of the AX in ordinary operation.
What does this all mean in practical terms for sport flying? Pretty simply, the AX will fly a bigger heavier model than an LA.
IME an AX will offer great vertical performance at 2.3kg, good vertical performance in a 2.5kg model, reasonable in an 2.7kg model, will kinda' still go vertical at 2.9kg, just, but struggle at anything above that. An LA will offer great vertical in a 2.0kg model, good vertical in a 2.2-2.3kg model, is still reasonable up to 2.5kg, but start to struggle above that.
With an LA, the engine itself is approx 100g lighter and you can get aways with carrying 8oz of fuel instead of 10oz if you want to saving another 50grams. Typical light good flying first low wing first tail dragger second ARF's in which an LA will perform very well would be a SIG Four Star 40, Great Planes Super Sporster MK II or my fav, The World Models Mfg Sky Raider Mach II. Stick an LA46, and 8oz tank and Bolly 10.5x6 or APC 11x5 on any of these and go ballistic. If it's only your second plane, the 46LA is a smarter choice and the perfect combo to maximise progress and have fun without breaking stuff. When your skills have developed to where you can handle the extra speed and power, simply space the bearers wider apart, then buy and bolt in your AX and go super ballistic.

Edited to remove foul language
#33
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From: Martinsville,
IN
OP Other members in my club said they had the perfect fix too. That was to take the idle screw out all the way and pitch it in the trash . Set the HS needle and wound up with a mediocer running engine. It's like this --even if you don't have a true LS needle it works about the same. Some carbs you look inside carb throat and see a gap between LS needle tip and spray bar. Now point your index fingers at each other and maintain a 1" gap , move your left finger toward your right finger and you will have to move right finger right to maintain gap. So when you turn a LS needle in a little too far (lean) you will have to turn HS needle out (richer) You have now narrowed gap and at idle where the LS needle almost shuts off fuel the HS has to be richer to force a little more fuel in smaller opening. If you don't richen HS needle you will have enough fuel till you get towards WOT cause you made a smaller gap. Your test at idle with high speed needle doesn't mean a thing because you don't need a maximum amount of fuel. But at WOT you need the maximum amount of fuel. The high and low speed setting effect each other in the total running range and anybody that tells you the low speed setting only effects the bottom 1/3 RPM range or what ever amount they come up with is full of baloney . If that was the case just throw away the LS needles and start engine at half throttle and let go of plane , hit WOT. If most engines LS wasn't set reasonably close they wouldn't even start. I hope I explained this clear enough.
#36
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From: FrederickMD
Sometimes a 10x5 adds that little extra sparkle that helps some trainers flying off of rough grass fields get airborne sooner.
Brad
#37
ORIGINAL: speedster 1919
OP Other members in my club said they had the perfect fix too.
That was to take the idle screw out all the way and pitch it in the trash.
OP Other members in my club said they had the perfect fix too.
That was to take the idle screw out all the way and pitch it in the trash.
One of our Smart-alec "experts" also suggested installing the carb from an .32/FX.




