All the bolts seem to be tight and I have a brand new radiator hose. What’s causing this pooling of coolant on top of the timing chain cover?
What I like to do when looking for a coolant leak, I go to the local advance auto parts store. Rent or borrow the coolant preasure tester hook it up pump up to 12 -13 lbs and you will see the leak.
I feel for you. I have a mystery leak on my car as well. I end up with a wet spot on the concrete after driving, and it’s not out of the pressure relief hose. I thought it may be coming out of the weep hole by the water pump bearing, but it isn’t. Yours looks to be the thermostat housing is seeping a bit.
Never thought of doing the pressure tester gig. I’ll have to try that.
You could have a leak from the front crossover passage of the intake manifold where it meets the head.
Fords are notorious for leaking out the thermostat housing right above the pool.
If you didn’t touch the thermostat housing I’d have to say it leaks at the bypass hose. With a mirror and a flashlight you might be able to see where it is trickling from. I had the same looking leak and after purchasing the contours correct molded hose from WCCC and good shielded worm clamps so they don’t dig into the rubber it cured that problem. Simple fix. That was on my 351w. Best wishes.
x2 on the thermostat housing.
A little different configuration so this may not apply to every one but I could not get the Felpro gaskets to seal under the 351C thermostat cover. Multiple attempts, clean surfaces, torque down tight, used the gasket with a sealant, nothing worked. It appeared to weep through the gasket material. The Loctite gasket forming sealant for coolant works great but you have to wait a while for it to cure.
It was not leaking before you changed the hose?
If that’s the case, you may have some schmutz between the hose and the outlet that needs to be cleaned off.
Also, don’t forget some of those water pump bolts go into the water jacket and need thread sealer or the old sealer has failed. I can’t remember if that top left bolt is wet as I do all of them when putting on a pump.
TG