I recently removed the dual Serk cooler from my old Perkins 6.354 and replaced with the following Mr Cool unit. Works a treat in tropical waters.
Perkins Dual Oil Cooler NA004139CN Replacement Part
Replaces Perkins NA004139CN Dual Oil Cooler
17-1/2" Overall Length.12" Bundle. 3/4'' npt oil, 3/8'' npt transmisson oil
1-1/8'' seawater connection.
Copper Nickel, for superior corrosion resistance in salt water applications.
This is a Mr Cool (USA) marine part MRC NA004139CN.
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