Recently I bought a 2001 F-150 Super cab that needed a lot of work but I got it cheap. One of the many tasks on my punch list is draining and replacing the engine coolant. I looked in the owner's manual for information on coolant capacity. I find it hard to believe that there is as much in it as they say. I drained the radiator st the drain valve on the lower right side of the radiator and I only got about five quarts out of it. In order to keep it from getting a vacuum I took the top radiator hose off the radiator and removed the cap on the fill tank. Am I missing some critical step in draining out the coolant? I even started it up a few times but that did not make any additional coolant come out. Does anyone know what the total fill capacity is for the 4.6 with the single tube row radiator is?

 

Holds about 4 gallons... There are always 2 gallons or 10 quarts in the motor BLOCK after you drain... To get a good FLUSH you need to use a garden hose, etc.......... I cut one of the heater hoses above the passenger valve cover and added a TEE with the third leg being a garden hose fitting.. I connect the hose at that point, open the drain valve and leave the overflow lid off, start the hose and start the motor... water flows out of both openings and should flush the block , radiator, and heater core... When your all done, remember you will have 2 gallons of water in the block.. If it is REAL CLEAN that's probably OK.. if it is well water or similar, I buy several gallons of DEMIN water at the grocery store and addd / run motor/ drain... add/ run motor / drain... after 3-4 cycles you have all the "house water" out of the block and should have 2 Gallons of DEMIN water in the system... I then add 2 gallons ( or 6 quarts) of 100% antifreeze .... measure the freeze point .... if your at ZERO to minus 10 and want it LOWER, then drain out 6 quarts and add 6 of PURE antifreeze to get down to your required level...... sometimes you can use compressed air to blow out an extra quart or so from the block.... Don't pressurize the system, just blow out.

 

 

I have one of those tee fittings someplace but as you say, I have issues with mixing in common tap water, I would rather just get rid of what is in there. I'm thinking of taking loose the upper radiator hose and applying air pressure there from the exhaust port of my shop vac. That would eliminate the possibility of damage from too much air pressure yet provide enough volume of air flow. Do you know if there are any accessible block drain plugs on the 4.6? You thoughts on this ???

 

There are no block "drains"... there should be a couple freeze plugs under the exhaust manifold areas, but not easily accessable... you might take the thermostat out to get better suction / air flow.

 

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