2007, 4.0L, Explorer, 113,000 mi. Week ago noticed coolant expansion tank empty while hot and cold. Looked inside ex. tank and looked like it had not seen any action in a while. Looked inside radiator and coolant level was about 1 inch to 1.5 inches below bottom of rad. cap would be...approx. level with rad. seam, where black plastic top of rad. attaches to metal portion of rad. I filled expan. tank to "cold fill" line. Kept an eye on it while doing light, around town driving. The expan. tank level (cold-fill) didn't change.

Friday, my wife returned from work (30 mi., interstate drive). After being parked for 45 mins, went out to find fluid puddle at very front of car. Expansion tank was empty. Looked in radiator, and it was about one inch to inch and a half below bottom of rad cap...about level with rad seam, where the black plastic top is attached to metal. I topped off the rad. this time, along with filling expan. tank to cold-fill line. Turn car on, and after warming up coolant starting coming out from what appeared to be the seam at the top of the rad., where the black plastic portion meets the metal part of the rad.

As finances are a greater issue in my household than ever before (out of work for 10 months), I need to try and address/remedy the situation at home, before turning it over to the experts. I'm considering trying one of the radiator sealant products. Have you had or heard of experiences with these products? How about using it on a leak in this location? Any issues to be aware of? Any advice on application? Suggestions on brand to go with? Sincere thanks for any and all feedback.

SmittyVIP

 

Stay away from the "MAGIC" fixes..

I have had luck with seam leaks,

• Uninstall RAD,
• gently release the aluminum tabs,
• remove the tank,
• clean the gasket and channel,
• apply high temp RTV to gasket,
• set gasket and tank on rad,
• apply gentle pressure (to seat),
• let set overnight,
• clamp down the tabs (compress gasket),
• reinstall rad..

.... Philip

 

since you know where it's leaking & it's only the tank to core seal I'd just throw a 1/4 of a tube of Alumaseal in it. Some folks prefer using a dash of ground pepper, but i'd just use the Alumaseal.

When the level in the overflow bottle starts rising as the engine warms up & dropping as the engine cools down you'll know your leak ihas been fixed

 

some one I knew used alumaseal and it clogged a water gaket in the engine block. I would go with the first recommendation.

 

xxxxxxxxxx

 

If you can see the leak in the radiator, i would try to fix that as mentioned. For sealers, i have used Bas Leak Copper headgasket/ block sealer to repair pin holes in gaskets or cracked heads. It works great for that.

 

I have the same problem w/my '07 explorer, dealer wants over $600 to replace radiator. did you fix yours and how is is holding up?

 

Don't take something outside warranty to the dealer unless you want to spend way more than the repair is worth.
I have had good luck with just (carefully) tightening the crimps on the radiator core to tank connection, but the GM stop leak tablets really do work without clogging things up. They know their cars leak, so they have this to help with it.

 

I wish I could post a picture of what might happen to your radiator, depending, of course, on what type of product you use. I recently replaced the radiator on my '97 Aerostar and took the old radiator apart. The side of the radiator on the same side as the filler neck was coated with brown goo, as was the tranny cooler, which I'm sure reduced the effectiveness. The opposite side didn't have nearly as much, but there was still a coating. I can only assume the previous owner used some sore of stop leak.

A good number of the fins looked pretty much plugged. I couldn't see light through them. Rough guess is that the radiator effectiveness was about 60%. I wondered why my Aerostar ran hot on days that were not that hot (80F), even after replacing the fan clutch and thermostat. That crap is still coming out of the cooling system after a good number of drain/fills and a professional flushing. I'm concerned that my new radiator might get plugged up from the residual stuff that's left behind and flaking off.

I understand that money might be tight, but I would avoid the stuff. If you do the job yourself, you should be able to get parts for less than $200. If you pay someone else, you'll pay that much in labor.

 

That's why I would never recommend Bar's Leaks or that sort of gunk. The GM tablets are a powdered vegetable material that expands to plug the leak and doesn't plug the cooling system up. It's one of the rare well-executed good ideas GM occasionally puts out.