Re: Temperature connection at the head

Posted by HH56 On 2024/2/29 15:59:57

There should be space in the water passage behind the opening where coolant can freely circulate around the bulb. It it looks or feels like a solid surface after removing the nut the bulb is most likely broken off the tube and stuck in the opening. Calcium and rust can do a job better than some glues and cause the bulb to almost become solid with the head.

Sometime a penetrating fluid or a commercial lime dissolving product continuously applied over a period of time will free it. Other times a rust and cooling system cleaner in the coolant such as oxalic acid will remove enough of the calcium or whatever to free the bulb. Other times it has had to be drilled out.

Most Packards used a bulb with a shoulder and a specific length nut that forces the bulb to seal against a smooth seat in the head. If you use any mechanical means to free the bulb take care not to damage that smooth seating surface or it could be hard to stop any leaks around the nut when things go back together.