How many tubes of RTV should I use...

to seal a water pump? '94 Dodge Shadow 3.0. Always ran hot. Did the usual, verified gauge, cooling fan, etc. Even running down the highway, it ran hot. After further investigation, pulled the radiator and popped the plastic end tank off.

The black stuff is RTV that apparently oozed through the coolant system after the previous owner had changed the water pump. The crusty scale is probably from running straight water as a coolant.

radiator shadow.jpg