1993 Johnson Evinrude "ET" 90 degrees CV Service Manual, P/N 508285, Page 34Get this manual
AnodesTesting and Replacement Erosion or disintegration in salt or brackish water indicates the anodes are performing their functionThe anodes should be inspected at intervals and replaced when necessary, or corrosion of the engine will increase
r:::=J If any anode has been reduced to 03 its original size (113
eroded), it must be replaced! To increase the duration ofthe anodic protection, the starboard stern bracket (on some models) is drilled to accept an additional anode
rv f21 1est for proper installation ofConnect one meter lead toana the anodeCalibrate ohmmeter on high ohms scalepowerhead ground and the other lead to the anodeBe sure the surface of the anode is clean to make good contactThe ohmmeter should show low readingIf not, remove the anode and clean the area where the anode is installed The mounting screws and the anode itself should also be cleaned Install and retestINotel Do not paint or coat the anodes or their mounting surfaces