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Harig 612 Oil Pump Tubing replacement and machine cleaning.

bigwave

Aluminum
Joined
Jan 24, 2020
Hi folks,

I've got a new-to-me Harig 612 hand-operated surface grinder circa 1993.

The clear vinyl oil pump tubing is extremely hard so I would like to replace it before I put the thing into service. There's also a fair amount of schmutz between the way cover leaves which I would like to clean if possible.

Does anybody know if the tubing can be replaced without removing the motor and/or spindle?

I can peek under the front way covers and see the top of the column. The rear column cover is glued to the bottom of the column with silicone and blocked by the motor. I can't remove front or rear covers without spindle/ motor removal.

I've not found an actual service manual -- just the Installation, Operation & Manual which has no tear-down procedures. I gather these things were never intended to be serviced by mere mortals..

Thoughts about Cleaning and Tube replacement?

Regards,
Dave
 

CarbideBob

Diamond
Joined
Jan 14, 2007
Location
Flushing/Flint, Michigan
The front cover is removed by taking out the 6 screws on the frame and then it will slide forward a bit and can be spun 90 degrees.
This gets you to the tube.
If the wheel cover is off and the 5 spindle mounting screws are below flush the covers will slide all the way off.
These 5 screws in the snout hold and align the spindle. If you remove them the spindle needs to realigned to the table ways at reassembly.
To get the rear covers off you have to remove the spindle.

There is a filter screen in that round thing attached to the oil pump. It should be cleaned along with the oil sump.
The needle valve controls oil flow amount to the table ways. In general do not adjust it.
Bob
 
Last edited:

bigwave

Aluminum
Joined
Jan 24, 2020
The front cover is removed by taking out the 6 screws on the frame and then it will slide forward a bit and can be spun 90 degrees.
This gets you to the tube.

ah..I did not think to try to rotate them. I think for now I'll avoid anything requiring re-alignment of the spindle.
I did notice the mostly clogged sump foot and will clean that.

Thanks,
Dave
 

majohnson

Cast Iron
Joined
Jan 3, 2013
Location
Erie, CO
Mine had the same issue, I went to the local bearing house and was able to replace all the clear tubing along with other parts for just a few dollars. It the same tubing and parts for manual oil pressure gauge they use on semi trucks.
 








 
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