So the manuals say that the cooling system holds about 3 gallons of coolant.
Opening the drain on the radiator only drains about 1 gallon. I have read all posts about the coolant system on this site and it seems that there are no block drains on the 4L engine. So how am I suppose to drain the remaining coolant out from the engine?
I drained as much as I could through the radiator drain and replaced it with a premix.
The temperature got down to -18F the other night and the fluid got half frozen in the rad. (The block was safe as it was plugged in). I repeated the drain/refill steps but this is still just a half *** solution.

My question is: How to do a proper coolant change on a 4L Aerostar?

It is a 4L '93 short cargo with no second heater in the cab.

 

HD flush, clean and drain. Put in a jug of Prestone cooling system cleaner. run until hot.
remove radiator along with lower rad. hose.
remove thermostat and 1 heater hose from block/pump.
use garden hose turned on to low pressure.
flush rad., block thru thermo hole and thru lower hose connector on pump/reverse. flush heater thru heater hose removed.
run with clean water until clear out.

Lt. duty flush, leave rad. in and flush with hose.

seal with hand on opening and blow out all with air compressor.

reassemble without thermostat and fill with distilled water, run to heat with heater on max, drain via rad. spigot. refill with DW and repeat. repeat at least 2 times to clear out the tap water with chlorine.

flush out or remove the overflow tank and clean.

blow out with compressed air draining out of spigot
reinstall the thermostat.
fill with 1.5 gal jugs of concentrate antifreeze, not any of the 50% solution stuff. may have to run engine to get all 1.5 gal of concent. in
top off with DW.
use the 50% stuff for overflow tank 1/2 full and to top off.

 

The problem is not the flushing part. It is that draining through the radiator will remove less than a jug of fluid from the system. So after the flush (or just draining the old stuff) only less then half of the fluid will drain out.

 

When you flush with distilled water, assume you leave 2 gallons in the system after your best efforts to drain. Now you fill with 1 gallon of 100% anti-freeze and run the engine. The concentration is now 33.33%. Assuming you evenly distributed it, drain 1 gallon, and replace with 100%, and run engine again. Now you have 44.44%. You can do it one more time to bring the concentration up to 63.67%, which would probably be good for down to -50F.

 

That is exactly what I did except did not do the flushing part as I have no means to do that at the moment. I drained and refilled it twice.
It seems kinda ok now but there gotta be a better way than this.
I mean if I take my van to a repair shop I don't think that they will monkey around with multiple drains and refills to "ballpark" the coolant concentration.

 

just use a compressor set on 50 psi to blow out the block thru the thermostat housing hole with the thermostat out. seal off thermo housing hole with hand.
blows the water out of the block.
same with heater core/s, take off 1 hose.
no more than 50 psi.

who knows what coolant mix one comes out of Jiffy Whip service with. they hire the minimum wage kids to work there.

ever wonder why so many people come down with serious illnesses after eating at one of the Quicky Burger Slopomatic places?

 

disconnect lower radiator hose and run engine for a few minutes, all coolant will drain.

 

What is the difference between removing the hose or simply opening the drain?

 

The lower hose nipple may be at a lower point than the drain plug, and on the other side of the tubes.

Running the engine without coolant even for a few minutes, is a good way to burn out the water pump bearing. I wouldn't do that.

You might try lifting up the rear end of the van with all the hoses removed to try to drain more coolant.

 

I've done it like that since my '86, never any water pump damage, of course I'm talking no more than two minutes running the engine, it will expell all the liquid.

 

I just don't wanna believe that Ford designed a vehicle that requires a short 1/4" hose, an Allen key, a forklift, a helicopter, a time machine and a space ship with a superluminal WARP drive to do a simple coolant change.

I have had several vehicles and all could be fully drained by simply opening a plug (in some cases more than one). There gotta be a way to do this on an Aerostar.

Is there anybody who pulled and rebuilt a 4L engine?
I am sure that we have some members who are trained mechanics. I'd like to hear their opinion.

C'mon guys this is a mystery (to me at least) waiting to be solved.

 

there is a Drain Plug, the question is WHERE IS IT? I have the Service Manual for my 1997 4.0 liter (thanks to a friend here), and I cannot find any illustration that shows where it is. I did copy the Coolant Service Procedure and here's what it says:

Draining:
1. Shut off engine (6007) and allow to cool. (no kidding, a "procedure" to shut off engine??)
2. Remove the radiator cap (8100). Refer to above warning. (there is NO "WARNING")
3. Attach a 9.5mm (3/8-inch) inside diameter hose on the radiator draincock (8115) to minimize loss of coolant when draining.
4. Open radiator draincock and permit coolant to drain into a clean container.
5. Remove drain plug on cylinder blocks (6010) to allow coolant to drain from engine, if necessary.
(so where is it??)
6. Dispose of old coolant properly. Promptly clean up any spilled coolant.

Filling:
1. WARNING: USE CAUTION WHEN ADDING COOLANT MIXTURE TO RADIATOR TO AVOID HOT COOLANT OR STEAM BLOW OUT FROM THE RADIATOR. (duhhh, by the time one gets to Filling, the radiator is cold!!)
Note: Use the following steps to remove air from the cooling system and to make sure fill is complete.
Note: When filling a crossflow radiator (8005), allow time for the coolant to flow through the radiator tubes to fill both tanks.

Close radiator draincock and re-install cylinder block drain plug.

2. Fill the cooling system with a 50/50 ethylene glycol and water mixture. Allow several minutes for trapped air to escape (bubble out) and for coolant mixture to flow through the radiator.
3. Install radiator cap to pressure relief position by installing radiator cap to fully installed position and then backing off to first stop. This will allow any air to escape, and minimize spillage.
4. Slide heater temperature and mode selection levers to maximum heat position.
5. Start engine and run at fast idle (approximately 2000 rpm) for three to four minutes. Shut engine off.
6. With engine off, wrap radiator cap with a thick cloth, carefully remove radiator cap and add coolant to bring coolant level up to filler neck seat.
7. Replace radiator cap to fully installed position. Then, back off to first stop. Operate engine at fast idle until the upper radiator hose (8260) is warm (water thermostat (8575) opens). To check radiator, shut engine off, wrap radiator cap with thick cloth and carefully remove radiator cap. Add coolant if necessary. Replace radiator cap to fully installed position.
8. Open the small cap on the top of the radiator coolant recovery reservoir. The large cap is for the windshield washer reservoir. NEVER put coolant mixture in windshield washer bottle.
9. Using a suitable suction gun, remove all coolant from radiator coolant recovery reservoir.
10. Add 1 liter (1.1 quarts) of 50/50 mixture of ethylene glycol and water to the radiator coolant recovery reservoir. Close the small cap.

And Feliz Navidad!

 

both my Jags, a 4.2 liter and a 3.8 liter, have "Drain Spigots" on the driver's side of the block, very interesting little "faucets" (I don't know what else to call them), which positively seal (no leaks) and when you open them, they allow draining of coolant from the block.

 

Thanks Jose! Now we are talking.
So there IS a drain plug on the block. (new plug on the block ... hi..hi).

Since coolant change is a regular maintenance item that drain plug must be relatively easily accessible from below. I have a feeling that it will be at the same location as on the 3L engine. Small, rusted-shut plug just below one of the freeze plugs.

I rest my case for now as I have no any means to actually check it out.
It was -25 F (-32 C) at the morning. I went out and checked the coolant. It did not freeze in the rad so I guess it will be fine. At least as long as it is plugged in overnight. I might drain and refill one more time just to be sure.

Thanks for all the help y'all!

 

you welcome DMTR!
I bet it's one of those plugs similar to the filler hole at the rear axle, that you can use a ratchet to loosen and tighten. I'm going to check too, if I find it I'll try and get a picture.