Diaphragm pump maintenance

[rjines]

Just wondering how often to change the food grade oil on my diaphragm pump? The oil is a little dark but no foam or milky look to it. I use this pump to pull some vacuum on my lines as well as pump my sap to my 1000 gal stainless tank at the sugar house.

[shane hickey]

Havent chaged mine in 5 years. I probablu
Change it when i have to change out the
Diaphragms.

[rjines]

Thanks for the info, I was told every other year would be plenty. Just want to stay on top of things.
I guess that's one less thing to do on the list.