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Air Bleed Adjustment LA 46

Old 10-06-2002, 02:19 PM
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Default Air Bleed Adjustment LA 46

Can anyone tell me what the base-line setting for the air bleed screw on an OS LA 46 is? One of the local "experts" told me you opened it up inserted a straight pin, then turned the air bleed screw in untill it cotacted the straigt pin. It seemed a little arbitrary to me, but he has 27 years experience and I'm working on week 2.

Now when we fly the plane (Eagle II) it still seems to sag, in what I'm told is a lean condition about halfway through a tank of fuel, even with what I think is a way too rich needle-valve setting. I've got about 8 flights on the engine, plus a couple of tanks run through on the ground, so I'm assuming the engine should be getting towards being broken in. There are a couple of LT-40's at our field, one with a TT Pro 40 , and one with a TT Pro 46, and they just sing! My engine will hardly pull me over the top of a loop!

I want to get back to base-line settings and tune it as per the owner's manual and see if I can get it sorted out.

Thanks in advance!
Old 10-06-2002, 03:27 PM
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Default Air Bleed Adjustment LA 46

.40LA is a rather simple engine.. using the pin is a good way to set air bleed, yes.. I have a few of these motors and recently ran into a problem with one which was reasonably corrected..
Remove motor and make damn sure cap on back of motor is screwed on tightly ..
A help to an LA making a little more power is to open up muffler
and remove the baffle.. It is a small 'funnel' shaped restrictor in
side of muffler.. Removing it will not cause a loss of fuel pressure..
However, make SURE pressure line IS open <nipple> and that the
vent tube in tank is unobstructed, i.e., hitting top of tank..
These engine are not as powerfull as a TT Pro, but they should fly a five to seven pound plane around well..
Also, if you use a 10X6 APC prop it will do better..

Old 10-08-2002, 07:30 PM
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Default Air Bleed Adjustment LA 46


We set the air-bleed screw so that it blocks 1/2 of the hole. It gets adjusted from there once we've gotten the high-speed needle set correctly.

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