Coolant filling procedure on 2008 Explorer V8 4.6L

[fridayshoes]

What is the procedure for topping up the coolant? Do I top up the expansion bottle or top up the radiator directly or both?

Thanks

 

[Flag Gibby]

Unless you have a leak somewhere, the reservoir (expansion bottle) should still have some coolant in it so just add some to the reservoir. Only to the full cold line stamped on the side of it. If the reservoir is empty then you need to start looking for a leak and get it fixed ASAP.

 

[makuloco2000]

Pull the cap on a cold radiator and make sure it is filled to the neck. Next make sure the reservoir bottle is filled to the cold range and you should be good. Any reason you think its low? I have a video on my Youtube Channel on how to replace the radiator and common leak points and also filling FYI.

 

[fridayshoes]

Thanks for the help, I noticed the radiator fans kicking in a day or so ago, so checked the water and the expansion tank was low. The vehicle was last serviced 8 months ago, so I'm just trying to determine if its down to natural usage or whether there is indeed a leak (hopefully not). I did a quick check under the car and there's no puddle or obvious signs of water dripping down.

Thanks for the help, I'll post back my findings if I find anything wrong.

 

[fridayshoes]

Okay, I topped up the expansion bottle to the full line, I also topped up the radiator at the filler to the brim and left the car overnight.

In the morning everything was as I left it with no puddles or drips coming from underneath the car.

I took the car out for a 20-30 min drive this morning, parked up with the engine off and then checked the situation.

Underneath the car water was dripping off both both corners of the radiator, I then checked inside the engine bay to see if I could find the source of the problem.

I can see that water is seeping/pushing out from the filler cap on top of the radiator. The expansion bottle is also empty.

Should I just replace the filler cap? Or is something else causing the water to push past the cap? Surely it should be pushing into the expansion bottle?

 

[Flag Gibby]

It could just be that your radiator cap is defective and leaks once the system is pressurized forcing the system to pull from the reservoir to keep the radiator full. I would pull the cap off and check it to see if the rubber gasket on the inside of it is cracked or missing. If so, just get a new one (radiator cap) and hopefully everything will be good at that point. Some individuals here recommend going with a lower pressure cap in order to hopefully extend the life of the cooling system since the radiators are known for prematurely failing.

 

[fridayshoes]

It could just be that your radiator cap is defective and leaks once the system is pressurized forcing the system to pull from the reservoir to keep the radiator full. I would pull the cap off and check it to see if the rubber gasket on the inside of it is cracked or missing. If so, just get a new one (radiator cap) and hopefully everything will be good at that point. Some individuals here recommend going with a lower pressure cap in order to hopefully extend the life of the cooling system since the radiators are known for prematurely failing.

Yep, it was indeed the radiator cap, the rubber seal had split along the edge. Bought a new cap from Ford, got little chance of finding the lower pressure variety out here in Dubai so just had to go with the standard one that the dealer has (Cost 100 AED). Seems to have resolved the problem, no leaks coming from the top and no water loss.