"Karl Townsend" remove .NOT to reply wrote
in message link.net...

The coolant pump on my Mazak M4 has slowed down to the point I can
pee that fast.

Or, is it worth taking the pump apart to see if its just gunked up?
I put a water hose on end of the line and backflushed it today - no
problems found. The pump is developing very little pressure.


Most coolant pumps are of the in-tank style: the motor is suspended above
the coolant tank, while the pump housing, shaft, and impeller are submerged
in the coolant. These are fairly simple pump designs with not much that can
go wrong with them.

If the output volume on your pump has diminished, there are several likely
reasons:

1. The pump inlet is obstructed with chips or gunk.
2. The pump outlet is obstructed with chips or gunk.
3. The coolant distribution plumbing is obstructed with chips or gunk.
4. The impeller is fouled with chips or gunk.
5. The shaft bearings/bushings are gummed, corroded, or shot.
6. The motor bearings/bushings are gummed, corroded, or shot.
7. The motor is failing.

I would certainly try to diagnose and correct the problem and/or rebuild the
pump before replacing it. Most of the problems listed above are easy to fix;
only reason #7 would probably warrant replacing the whole unit.

- Michael