90 TLDI, not bashing

[lots of boats]

Over a year ago I brought water pump problems to the attention of my dealer and the Tohatsu Regional Sales Manager. About two months ago Tohatsu's Market Sales Manager, Tohatsu's Regional Sales Manager, and Tohatsu's National Sales Manger, all were kind enough to come down to my boat together where I showed them 10 damaged water pumps, and dismantled the water pump from a Tohatsu 90TLDI and a Yamaha Enduro 60, so we could compare the parts. They were also kind enough to give me two new drivshafts they brought with them. So far I have found two other Tohatsu users with similar problems. My question for the forum is whether anyone else has had the same problem, and solved it. The problem is as follows: If you put a new Tohatsu pump key into a new driveshaft, it is loose. When you put a new pump impeller on a new driveshaft with a new key, the impeller can be rocked back and forth. The result of the problem is that the water pump fails. I am not bashing Tohatsu, I am stating facts, and seeking a solution.

Cheers.