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The Artful Bodger
12-18-2010, 01:44 AM
The coolant pump on my lathe has run out of puff and can no longer push more than a dribble up to the nozzle. It is a generic Chinese 12x36 lathe and the pump came with it.

Before I start building a new pump etc how could I make this little motor run faster?

winchman
12-18-2010, 02:02 AM
I'd first check the chip screen, pump intake, and impeller for obstructions. We've had problems with the pump on the Doringer getting cloggged with paint from the inside of the coolant tank and grease from the turntable slide.

There's no way to increase the motor speed without changing the frequency of the power to the motor.

lakeside53
12-18-2010, 02:08 AM
As above, but also - if your impeller or internal chamber is worn, then it may no longer puff even if you do clean it out.

oldtiffie
12-18-2010, 02:31 AM
And don't forget to see that the supply hose and tap/cock are not obstructed either.

Make sure that there is enough cover to the pump suction port to avoid "sucking air" as it will cause cavitation and "los of pressure".

The Artful Bodger
12-18-2010, 04:00 AM
OK guys, thanks for the advice, I have now been through all that, even trimmed the impeller and put packing under to reduce the clearance with the cover plate. Checked the wiring and even tested the capacitor.

The answer is however an obstruction, an obstruction caused by them using those really cheap metal clad hoses meant for use in showers etc. The inner tube is of materiall marginally heavier gauge than a Chinese condom and of course the tubes collapse and get twisted inside the metal sleeve because the end fittings do not swivel as they should.:rolleyes:

Off to the hardware shop tomorrow!