I have a 98 F-150 that I need to replace the coolant on. The owner's manual only refers to topping the coolant off. Is there an engine block drain plug (if so, can you guide me to its location)? Also, I don't see a traditional drain valve at the bottom of the radiator. Instead, I see a black, tee'd extension with a white plastic hex nut on one end. Is this the drain location for the radiator.
Thanks for any info!

Steve
Boise, ID

 

Hi Steve,

This is actually a very simple process. What you're referring to on the radiator sounds like the drain valve on the pet****. Spray a little penetrating lube on in because they do have a tendency to stick a bit.

Here are the procedures:
1. Remove the recovery tank cap.
2. Place some type of pan or bucket below the truck where the coolant is going to drain.
3. Loosen and remove the pet**** drain valve (the one you described before)
4. Allow all of the coolant to drain and then put the drain valve back in.
5. Use roughly a 50/50 mix of distilled water and coolant and refill the system through the recovery tank.
6. With the recovery tank cap still off, fire up the truck and allow it to warm up enough so that the thermostat comes on. (This will remove any airbubbles in the system. The coolant level will probably drop down once the air leaves when the thermostat opens up.)
7. Determine how much more coolant you need and fill it up as necessary.

Note: if you wanted to do a true "flush" of the system, do everything the same from steps 1-4, but replace step 5 with this: add either a system cleaner or very clean water, turn the engine on, allow if to warm up so that the thermostat opens. Allow the engine to cool a bit, drain the water or cleaner, repeat this until your fluid drains clean.

From there, repeat steps 6-7 and you're done! Hope this helps, good luck with it.

 

Oh, this is kind of funny. There must be some type of filter that automatically blocks out "dirty words" on these forums. The words above that looks like this "pet****" aren't dirty slang. I'll try spelling it incorrectly to see if it will come through. The part of the radiator I'm referring to is pronounced, but not spelled, "petkock." Hopefully, that won't get edited.

 

Also,turn the heater on the highest setting,fan speed on high also during and after the flush and fill.That way you circulate the heater core and fill it also.

 

Thanks for your replies! I'm flushing the entire system, through the heater core, and am wondering if anyone has accurately calculated how much fluid the core, engine block, and hoses contain so I can get as close to a 50-50 mixture as possible? I know that if I add 50-50 from the start, it'll be pretty diluted by the time full circulation occurs!

Steve

 

If you want to be exact about re-filling it correctly,then pull the block drain plugs and the lower radiator hose.The 4.2 cooling system holds 15.7 quarts with out a/c and 17.3 with a/c.You might not get it all out but pretty close to 85-90% by doing what I said.Then just go with a 55/45 mixture.Or even 60/40 wont hurt.

 

Prestone makes a neat flush kit that sells at walmart for about five bucks.

It is a plastic hose adapter, so that you can flush the whole system in your driveway, and get it crystal clean, then drain it and refill with the proper mixture.

JH

 

Antifreeze must be collected and recyled by law, don't just flush it down the drain.

 

who said I wasn't draining it into oil pans and then transferring the fluid into milk jugs?

Everyone is a quasi-treehugger including me at some times.