You only need to replace the base if it's damaged or melted slightly.... I always put a very light smear of grease on the inside of the impeller housing... It makes the impeller easier to install and gives it a bit of protection on the first start before the water can get there..... Doesn't have to be water resistant, any grease will do....
Chris............
P.S. trash the solec and get a genuine manual... You'll thank me....



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The world takes on a whole new perspective when viewed from 100' below...

1972 Bertram 'Bahia Mar' 20
2006 Mercruiser 4.3MPI (OW617679) w/Alpha 1 Gen II (OW829301)