I think the fact that the engineers didn't see a need to include a filter in the design indicates that they were very comfortable with the ability of the pump to handle trash. You can pump some nasty stuff with diaphragm pumps.
look at picture of diaphragm
http://www.nationalchevyassoc.com/te...og.cfm/2/20/14
You should have an automatic emergency shut down switch triggered to oil pressure I think, if you are gonna keep running your electric for a little while. Safety issue. Ask others. Topic was discussed somewhere around here recently.
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