ProMinent DULCOMETER PH-501 Assembly And Operating Instructions Manual page 852

Refer to FIGURE 3-1, page 17. Remove the breather (B) from the gear cover. Add oil to the
gear case until oil reaches the center of the oil level gauge (H). Secure breather (B) in the gear cover.
Add fresh oil as required to maintain proper level. The oil level should be at the middle of the sight glass when
the machine is not operating. Refer to Figure 3-2, page 18, for approximate oil capacities.
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