[captainkaos]

I'm working on an 80's vintage Mitsui Seiki horizontal mill that has spindle lube issues.
It has an air powered lube pump and an air / oil mixer distribution system with a line to each bearing in the spindle.
There is a Klixon style pressure switch in the oil line that closes at about 150 psi.
The control needs to see this switch closed for about 20 seconds, but we get less than that.
Sometimes a lot less.

I'm unfamiliar with this type of system and to effectively repair it, I need to know how it works.

Can anyone here explain it to me?
Extra emphasis on the air / oil mixer.

Thanks......Rob.

[williamtraughbe]

It's most likely no more than a malfunctioning pressure switch. If it is functioning it should keep the signal to the control all the time. Good luck.

[underthetire]

Most likely a meetering manifold issue. One of the plungers inside is probably not closing all the way.

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[williamtraughbe]

You should be able to remove the oil feed line and count the drops per minute. The spindle manufacturer should have a manual with the info for your paticular spindle. There will be an adjustment on the air-oil aperatus. I've never had an issue with the air oil on my grinding machines. The control has no sensor to set of alarm. I think your having a spindle coolant flow issue. If the cooler is malfunctioning it will cause an alarm to trigger.