Just replacing the thermostats on my 1990 V6 and typically one of the four bolts was a bit of a terwat to get out with a white fluffy powder coating the threads !
Cleaned the bolt & threaded hole out thoroughly and if it was on the car would give it a smear of copperease on reassembly but having read about galvanic corrosion on some of the posts wondered if waterproof grease was a better option? I reassembled the gearbox after fitting the impeller with grease as it's in the salty stuff but wouldn't expect much at the top of the engine.
Any thoughts appreciated.
Thanks
Waterproof grease is the better option or graphite dust for the bolts but I wouldn't use any copper based products on an outboard especially below the waterline .
