on a 351W Ford repair. Coolant drops, then no heat. Seep is on bottom of front cover, and on top, on block areas below the thermostat neck. Instinct is to remove pump, find if deterioration exists. But I read about aluminum deterioration and seepage from aluminum plate behind water pump. I have all hoses off, ready to break bolts loose on pump in morning. Shroud and fan are off, radiator still in. This would be the time to plumb things back to normal, fill system, positively locate leak under pressure tester. Last time, I could only see it dripping down to bottom of pan, too much in way to pin down source.
Suggestions? No play or bind in shaft of pump. Condition on outside nice, coolant color excellent.
What would explain occasionally sticking thermostat and this seepage repair? I think bigger cooling system issues exist.
Pump vanes looked new. Corrosion had built up on plate of pump on timing chain side. A couple bolts were badly crusted, required extra effort to remove.
I hit cold temps, so re-strained fluid that had normal green color. A radiator went in last year. I strain through a shop cloth, and a lot of brown appeared. So a flush and chemical long chemical clean are needed. I expect plugged something, maybe heater core. When I get the thermostat to work and close, pretty normal operating temp per gauge and good cabin heat.