I drained the radiator and block on my 02 F-150 4.6 and I only got 3 gallons out of it, it only took 3 gallons to fill up the degas tank. The manual says it has a 5 1/2 gallon capacity.

I'm flushing it with distilled water to get all the old junk out because it was nasty.

Should I put 3 gallons of 50/50 mix in, or should I assume that there is an extra 1 1/2 gallons of water somewhere in the system and add extra coolant to compensate?

 

Did you drain both sides of the block ? As long as you flush, you should be alright. Just test it when thru. After it's been mixed with residual and you purge air.

 

There is coolant in your heater core too.

Run the truck (make sure its warmed up and the t-stat is open), turn on the heater to full blast and have someone pinch the return hose as you add 50/50 until it fills up.

 

That's right, I change the thermostat when I flush mine out, "cold" . As far as Capacities go -

2002-2003 4.6L Capacities/Cooling

Standard Cooling = 25 qrts.

W/aux cooling = 27.2 qrts.

 

where is the block drain?

 

Drivers side, just above the dipstick port.

 

Ive always seen the capacity as 3 gallons

 

What! Really? Alright, I'll check/results -

Resource #1 -



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Resource #2 -



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Resource #3 (The one that doesn't lie. Ford Service. ) ~

 

Looks like the first two may be wrong ? They are 3rd party.

The capacities in the chart from Ford Service is trustworthy. Thanks Patrick, - for getting me to check that .

 

No problem

So old dogs do learn new tricks

 

Why does my owner's manual disagree with all those charts? It says a 2003 4.6 holds 20.6 quarts.

 

I drained the drivers side of the block. I think the pasenger side was behind the starter so I left it.

I have a 4.6 with the single row radiator. It looks like it should take 4.85 gallons.

Can there be 1 1/2 gallons in the heater core? I would expect that draining the radiator and block would empty the heater hoses and basically everything except for the heater core.

 

I don't know, - they are all different tho. Not sure what else I can check, -I suppose I could look at the paper manuals. Say the word and I'll go look.

biggrey - I drain the rad, then the block. I don't have two block plugs, just one on the drivers side. I've pulled the starter and wire wheeled the passenger side of the block looking for it, - doesn't exist. Anyway, I pop the thermostat and that's when I get more from the block. Then pull your heater core line for the rest. Then flush from the highest point. I purge the air from the core line as well. Sometimes it's a chore getting air out of these systems, but you need to, this avoids hot spots and gurgling effects after your thru.

Some have posted that they refill from the degas bottle and all is fine. I've tried that quite a few times and used the factory bleed and burp procedure only to still have air in the system as a result. Good luck with that, - if worse comes to worse, you can always pull from the highest point and purge the rest.

 

when you drained the rad did you remove the bottom hose or did you just use the drain on the passanger side.

 

I opened the valve on the passenger side of the radiator, and I pulled the plug on the driver's side of the block.

Today I pulled the heater hose and it was empty, so I'm getting the water out of there. I'm trying to flush the system several times this week to try and get all of the old junk out.