Hello, thanks again to everyone on this forum for your helps. This time it was my thermostat housing. 2000 Mercury Mountaineer 4L SOHC. The plastic heater hose nipple broke off and blew coolant all about. Fortunately I was on a side street and could pull over and get the engine shut off quickly so I dont think there was any deep engine damage. (the oil on the dipstick looked and smelled fine) I took one look at how deeply buried the part was under the throttle body, hoses and wires, and called my last resort mechanic. Fortunately he was booked solid for at least a week before he could even look and give me an estimate so I dug in on these forums and discovered that it was indeed possible. I have a buddy Myron who is a very good shade tree mechanic and has mentored me on many repairs on this olde rig, and he encouraged me to proceed. I did not have to take off the intake manifold (which was good because last year I paid a ton to have it tested and sealed so I didnt want to disturb that too much!) . I did have to remove throttle body, and the alternator and bracket so I could access the lower bypass hose. My local AutoZone quote $133 for the replacement part. I bought the Four Seasons $19 unit from Rock Auto. Some forums discouraged that unit but I am glad I didnt see those comments until after I ordered. It was the entire lower and upper housing, with thermostat, and both sensors, and a perfect exact replacement. I assume the plastic may not last as long as OEM, but I expect to be replacing this rig this year anyway so I was OK with that (AND I am becoming a huge fan of Rock Auto. A few weeks ago I bought a serpentine belt from them, and it arrived in half the time they predicted. Same with this housing. Ordered Friday afternoon, no special shipping, arrived Monday morning! )
I read on this forum about vacuuming out the engine coolant port and water pump and so glad I did. The sucked-out coolant was chock full of plastic shards from the disintegrated housing nipples. That would have been a mess had I left it all in. (I assume I missed some, but I was pretty thorough. I kept sucking and checking the fluid until it came out clean) I was pretty worried about my ability to get everything back together correctly. This is one of the most complex repairs I have attempted solo but I took good notes, watched several youtube videos, labeled all the wires, etc, and it all went back in pretty easily. no leftover parts! Refilled with fresh coolant, fired up and all good. thanks again so much to you all.
