On 2009-11-05, Jon Elson wrote:
Ignoramus8745 wrote:
Picked up a "2.98 kW" (4 HP?) 60 gallon Speedaire compressor with a
self described "bad motor" for $50.

I am kinda hoping that the motor is not actually bad.

Upon inspection, it seems that the motor has four terminals
1,2,3,4. Terminals 1 and 4, supposedly, are for line in, if i read the
label right.

There is no diagram for the rest, so, would it be correct to assume
that I need to connect 1 and 2, and 3 and 4? Or, if the rotation is
wrong, 1 and 3, and 2 and 4?

i
Probably not. I am guessing it is a dual-voltage
motor,

it is not

and likely you tie 2-3 and tape up for high voltage, and probably
something like line in on 1-2 and 3-4 for low voltage. But, it
could be a reverisble motor. Usually, reversible motors do not have
4 leads, but have a terminal board insde where you reverse two wires
to change the direction. Is there a nameplate? If not, there might
be a paper label somewhere under a cover with the wiring
instructions.

There is a nameplate:

http://igor.chudov.com/tmp/MC-261-Dayton-Motor/

it says connect to terminals 1 and 4 only. But maybe 2 and 3 were
connected somehow in the motor as it was shipped, but now they are not
connected to anything as of now.

I know that it is 230v only, and nowhere it mentions that it is
reversible.

i