I have a 1994 Lincoln Mark Vlll. It overheats even tho the radiator, thermostat, heat sensor, most of the hoses, have been changed. What gives, anybody know? Thanks.

Air bubbles in the system! You have to remove all the air bubbles or you will have nothing but headaches.

Yup. The system must be properly burped, its the reason most 4.6l appear to overheat. Direction right on hood or about.

Basically if your pouring coolant in the over-flow tank, well its wrong. You must always fill at the crossover tube. Top center front of engine. Fill, run engine (do NOT rev) and repeat until ALL air is out. I prefer to take it out for a drive when I cant get anymore air out in the driveway. I take it off-road to really shake any bubbles loose. Then repeat above again. Check in a week to be sure. That usually fixes it 99% of the time.

Have fun burping..

Burping the coolant is hugely important... put the time to make sure you have all the bubbles out before you hurt the motor.

Have fun burping..
http://www.gifs.net/Animation11/Creatures_and_Cartoons/Cartoons_Simpsons/Barney.gif

I prefer to take it out for a drive when I cant get anymore air out in the driveway. I take it off-road to really shake any bubbles loose. Then repeat above again. .

Try this either park in a steep incline/driveway or jack up the front about 6 inches to a foot.

Find a plastic funnel that fits snug into the crossover tube.
( I got a short necked funnel from autozone that fits perfectly)

screw/press the funnel into the crossover tube and mantain 3-4 inches of coolant in the funnel.
run the motor with the heater on

by jacking the front up, you help move the air from the back to the front of the motor.

The funnel trick gives the air that would normally be swept back into the system and upwards route to escape because it's higher than the engine.

When I do it this way, I usually get the car fully filled on the first try and rarely have to add more than a glassfull of water later.

give it a shot it works really well.

How long do you run it with the funnel in that position for Tommy?

How long do you run it with the funnel in that position for Tommy?

bout 15-20 minutes or until no more bubbles come out of the crossover

The funnel method sounds like a good idea.

it works really well...

the funnel I used had about a 2-3 inch short fat neck and was about 7-8 inches in diameter at the top

this might even be the same one.. but this is what you are looking for
http://images.orgill.com/200x200/6202493.jpg

I tried that method on the Mark I had with blown head gaskets... it shot coolant out of the funnel the entire time... it was pretty fun to watch lol...