[Rhodes22-list] ? frozen gear box housing on new motors?

[Robert and Sandra Fuller]

Hired a guy to do the initial oil changes on the Yamaha 9.9 with the boat in the water.  Figured I could have done it myself but then would have had to christen it Exxon Valdez II. He did a neat job.
Anyhow, he said he has seen numerous new motors, within a year or two, develop severe corrosion of the bolts holding the gear housing to the cowling of the shaft. And the housing freeze so tightly to the lower cowling that he had to hacksaw a slot between the two to pry them apart. Then repair the slot.  Apparently it is bad spot for electrolysis.
Since we were changing gear oil as well, he dropped the gear housing and coated the bolts and surfaces with flexible gasket sealer - which he says prevents the problem.
Wondered if anybody on the list had heard of or had this problem with a fairly new motor?
Bob F