Myford MG 12 Coolant Pump problem

[Bob RodgersonParticipant @bobrodgerson97362]

[Bob RodgersonParticipant @bobrodgerson97362]

A good year or so ago I switched on the Myford MG 12 Cylindrical grinder and couldn't get the pump to run in either constant mode or when switched with the work head. At the time I thought that possibly sediment had gotten into the coolant tank and stopped the impeller from turning but never bothered to check it out.

I have some bar that I need to grind down to size and I decided to have a look at it.

I first of al checked all of the fuses inside the control panel, all were good. Then l had to haul the tank out from behind the machine, to do this I had to remove the counterweight that provides the return force for the Wheelhead so that I had room to remove it. Once accessible I checked the tank and found that it was clean (apart from the coolant having a bit of oil on top). I couldn't find anything wrong with it so I took the cover off the pump motor and checked for current when the pump was switched on, there was absolutely no signs of any current getting to the motor.

Question is, where do I look or what do I check next. I'm sure it is a simple fault but it's tracing it that is a problem to me as me and electricity are not good friends, its just something that makes smoke come out of wires.

Any suggestions?

[Bob RodgersonParticipant @bobrodgerson97362]

Problem sorted, there wasn't a problem really unless I am counted as one.

When I went back into the workshop I checked again that I had current at the plug, lo and behold there was power this time. There are three positions for the coolant pump, one switches on with the Wheelhead, the other with the Workhead and the other position is off. When I checked the first time I must have had the switch set to Workhead but switched on the Wheelhead without realising, consequently no power was showing to be getting to the pump.

Once I had established power was in fact reaching the pump I removed the tank top complete with pump to give me access to the impeller to see if there was any movement because it is impossible to see any signs with the cover plate off the motor. Sure enough the impeller was spinning freely. If I had just thrown 8 gallons of coolant into the tank and switched on everything would have worked.

Oh well I guess I will be grinding tonight.

"Stop snickering at the back of the class you lot!'

[KWILParticipant @kwil]

Your problem was that you looked for "current" (as per your statement).

Current will only flow if you have Voltage (ie pressure to make current flow) through a circuit. As you found, no voltage = no current

[Bob RodgersonParticipant @bobrodgerson97362]

I should have said Voltage actually.

[mark costello 1Participant @markcostello1]

If You think that You are the only one Who is their worst enemy, I'll point out that the line starts over there and the end is almost out of sight. Forgive Yourself and continue making grinding chips.

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