When relatively new, a tool (whether a Mercury Service Tool or a work around) could be expected to do the job, If the last person to install the cover lubed the threads that may still be the case. Frequently the cover and gear case threads are corroded together so tightly that force alone will not remove the cover. IF that is your situation, there are several techniques to loosen the cover, It is not just a matter of squirting some skunk juice elixir…although that may not hurt. Either obtain the required Mercury Service Tool or make a work around tor same purpose, apply your preferred skunk juice to threads and after waiting for penetration. try to turn cover off in clockwise direction…the opposite direction of most threads. If it movers a little…more skunk suice and work the cover back and forth until it comes off, Keep in mind it is a Counter Clock /Wise thread.
If cover remains stuck, Beat & Heat. Use a hammer and a brass or aluminum rod to tap around the outside of the case over the area of the threads, Use soft metal rods to limit denting the cover. A nylon face hammer might do equally well. This technique shared by Bob Grubb, Heating the area of gear case over thread to expand the case even a little may help free up threads Use as much heat as you feel comfortable with….somewhere between too little and too much. No guarantee of success, but, worth trying.
If ALL ELSE fails drill and break cover into pieces. Never gone this far, but, some have. Unicast gear case on KF5 thru KG4 share same design plus and minus
Be sure to clean and lube cover threads prior to assembly and keep in mind cover is NOT screwed on tight.,,friction of impeller prevents cover from backing off.
Louis
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