Ford 8N dribbling coolant out of radiator overflow, not overfilled.

[repete]

Without a recovery system you'll always have air in the radiator due to thermodynamics. I would put a 2 liter bottle with the overflow tube submerged at the bottom, take a scotchbrite disc and clean up the top seal on the neck, and verify that the radiator cap has a rubber seal at the top and bottom, so when it cools down it has to draw fluid back in, rather than atmosphere. The bend in the filler neck shouldn't be an issue, unless there is a crack that would allow air back in.

Be sure the cap is correct for a recovery system:

Different Types of Radiator Caps for Your Vehicle

Radiator caps may seem like small, insignificant components in a vehicle, but they play a crucial role in maintaining the health and efficiency of your engine. The radiator cap is not just a simple cover, it’s a pressure valve that helps regulate the cooling system of your vehicle, ensuring that...

www.wheelmovers.com

 

[BossofBBQ]

Update: After borrowing a tester, I found no signs of compression in the cooling system. After having the radiator fill neck straightened, the problem went away. No more coolant dribbling out of the overflow.

I guess the neck was bent enough to hold the cap up and cause a bad seal.

 

[repete]

Update: After borrowing a tester, I found no signs of compression in the cooling system. After having the radiator fill neck straightened, the problem went away. No more coolant dribbling out of the overflow.

I guess the neck was bent enough to hold the cap up and cause a bad seal.

You prompted good conversation on cooling systems.

 

[John0829]

Glad to hear it was a simple fix in the end with plenty of hoops jumped though to get there

 

[ultrarunner]

Admirable you were not deterred…

 

[BossofBBQ]

Thanks again for all the useful advice folks!
I definitely learned a lot about cooling systems these past few days- very useful knowledge to have.