Overheating/Roaring Fan

[Striped Bastard]

Well I scoured this forum and decided to post my solutions. Same as others. 06 V8 and the overheating and roaring fan. Finally got time to change the thermostat and valve temp sensor. Knock on wood and constantly driving I feel that it's solved on my explorer. Had a radiator (leaking) and thermostat installed less than a year ago at local shop. After a few months the symptoms came back. No coolant loss, just "overheating". Windows down and no AC the temp stayed normal. Pressure check on system at a different shop and radiator is cracked on a bottom seam. JB weld and no leak. The shop that installed wouldn't make it right. Turns out either they put a faulty thermostat in or it blew the gasket(see pictures). While in there I installed a new sensor while I was in there swapping stats (alternator removed). Elevated front and spent a hour burping. So far so good.

Great resource here and much appreciated

 

[Bazz270]

What radiator brand do you have?

 

[94Eddie]

I suggest you change the radiator cap from the 20 psi OEM piece to a 16 psi cap. Many of us here have done this with no ill effects on the cooling system. I did it well over a year ago and have not seen one instance where the temp gauge went higher than it did with the 20 psi cap. IMO, the high failure rate of radiators in the 4th gen Explorers/Mountaineers is due to the 20 psi operating pressure in the cooling system putting too much stress on cooling components like the radiator, the heater hoses and plastic "Y" in this area. Maybe there is a use case where 20 psi is needed but I haven't seen the slightest increase in temperature through last summer running the AC on high in 105 degree temperatures. I live in the Mid-Atlantic region as you do so I expect you would see the same results as I do if you changed to a 16 psi cap. The link below is to the same cap I used.

MOTORCRAFT RS76 Coolant Reservoir Cap | RockAuto

 

[Striped Bastard]

What radiator brand do you have?

Not sure. Haven't looked. Shop put it in

 

[Alpsodelic]

I suggest you change the radiator cap from the 20 psi OEM piece to a 16 psi cap. Many of us here have done this with no ill effects on the cooling system. I did it well over a year ago and have not seen one instance where the temp gauge went higher than it did with the 20 psi cap. IMO, the high failure rate of radiators in the 4th gen Explorers/Mountaineers is due to the 20 psi operating pressure in the cooling system putting too much stress on cooling components like the radiator, the heater hoses and plastic "Y" in this area. Maybe there is a use case where 20 psi is needed but I haven't seen the slightest increase in temperature through last summer running the AC on high in 105 degree temperatures. I live in the Mid-Atlantic region as you do so I expect you would see the same results as I do if you changed to a 16 psi cap. The link below is to the same cap I used.

MOTORCRAFT RS76 Coolant Reservoir Cap | RockAuto

Does that actually fit a 2007 v8?

 

[D Hook]

Question: Does the lower PSI cap make a difference when burping the radiator? I had a 16psi cap installed, then had the water pump changed and I don't think the shop burped the system correctly. A few months ago I jacked up the front end and let it run for 30 minutes but no change in the fan roaring. It's even got hotter than normal when the weather is over 90 degrees with AC running. Cools back down if AC is turned off. I've put on the 20psi cap and am running that right now but the ambient temps haven't been as high as earlier this summer so can't tell if the roaring fan problem has gone away. Next to try is replacing the thermostat. But not sure which cap to put back on. No leaks anywhere and fluid levels are holding as they should. I ran the 16psi cap for about 18-24 months prior and no trouble.

 

[94Eddie]

Does that actually fit a 2007 v8?

Yes. It is a direct fit unless you have a radiator installed that won't fit an OEM cap.

 

[94Eddie]

Question: Does the lower PSI cap make a difference when burping the radiator? I had a 16psi cap installed, then had the water pump changed and I don't think the shop burped the system correctly. A few months ago I jacked up the front end and let it run for 30 minutes but no change in the fan roaring. It's even got hotter than normal when the weather is over 90 degrees with AC running. Cools back down if AC is turned off. I've put on the 20psi cap and am running that right now but the ambient temps haven't been as high as earlier this summer so can't tell if the roaring fan problem has gone away. Next to try is replacing the thermostat. But not sure which cap to put back on. No leaks anywhere and fluid levels are holding as they should. I ran the 16psi cap for about 18-24 months prior and no trouble.

I don't see why a 20 psi or 16 psi cap would make a difference when refilling the cooling system. I haven't ran into an occasion where I have refilled the cooling system while having the 16 psi cap.