Recently the hose "collar" (for lack of a better word) was sheared from the thermostat housing. The housing was the plastic version that has been superceeded by a metal version. I replaced the housing with the new model and replaced the thermostat too. I'm concerned about pressure levels. The radiator side is still plastic and I'd like to prevent another breakdown.

What would cause pressure levels to shear the collar off?

Would flushing the cooling system do any good?

What else could I look into?

Thanks for any response.

Kevin Moran
1988 300E 155K