On Gen1 vehicles, the 1987 FSM Vol. 2 shows a short length of rubber heater hoses inside the cab under the dash. This joint hose is attached between the heater water valve and the heater core. I have not had to make this repair myself, but it is the reason I carry a hose to bypass the heater assembly. It might be a good first place to check for leakage.

Checked the 89 FSM Vol. 1. The water valve/heater core configuration is the same as the 87 mentioned above.

Last edited by philCA; 08/29/04 01:19 PM.