Tom Miller wrote:

I volunteer at the local science
museum,rebuilding old machinery. Mostly steam and
early diesel tractors and road rollers. We have a
pretty good shop with a selection older, but good
solid machine tools. Among them is a Cincinnati
horizontal mill No.2 M1 ( serial F5409-6) made in
1946. Another of the volunteers(No , it really
Wasn't me) pulled the gearbox selector assembly
off the side of it as the machine appeared to be
seized. It appears that it somehow selected two
different gear ratios at once. It appears also,
that the gear selection is done hydraulically by
pistons which push selector arms in response to
the position of a multi-port valve .The question
is -how do you get the selector arms in the
correct position to re-assemble it. We will
probably have to replace the "o" rings on the
pistons as that is possibly why it selected two
gears at once.
Does anyone have any experience with this or a
similar machine? Am I looking in the correct areas
and are my suppositions reasonable?

We spent 2 hours today (and a fair amount of bad
language) trying to get those selectors in the
right positions to re-assemble it.

Tom Miller




Ive repaired quite a few of them so maybe I can be of some help. To
line up the shifters you should pull off the outside and inside plate on
the opposide side of the mill. This will gain you access to the inside
of the machine so you can make sure all three of the shifter yokes are
in the proper place. You have to set them up in the apporximate
position and guide them in as you put the shifter housing in place. Make
sure you get the little O rings in place at the bottom of the shifter
housing.


The first thing to do is to check the hydraulic pressure on the shifter
system. There is a port on same side as the hudraulic shifter unit that
allows you to measure pressure. I leave a gauge right in the port so you
can keep an eye on it on a continuing basis. I think the pressure
settin should be about 300 lbs/ inch. The pressure adjustment is in the
back over to the left of the main drive pulley. It should have a plate
on it marking it as such.

I would suggest you should get a maintance manual of your particular
machine. The information above is from my experience working on #4's
and bigger, but they are all basicly the same.

When shifting gears, there is a lot going on inside of that machine.
Make sure that the motor is turning the right way. There is an arrow on
the main drive pulley that indicates the proper rotation. If you have
proper rotation you will have hydraulic pressure. The gear pump is
driven off the input power shaft before the clutch. One big problem is
the pickup oil screen. After years of use it will get gummed up and
will cause the oil pressure to drop.

You can check that the shifte forks are free. They should move easily
with a little hand pressure. Watch out for the residual oil that will
be pushed out of the input ports.

Watch out, cinci uses double set screws in many places. You have to
measure the depths to make sure you got both of them out if you are
removing a part.



John