Clogged radiator reservior tank

I have a dodge neon that overheated. I tried adding coolant, but the little tank above the reservoir is apparantly clogged. Nothing goes into the tank, it just goes out the overflow onto the ground. I know it needs a flush and fill, but before I get it done, is there a way to get the tank unclogged?

If coolant from the radiator is pushing into the reservoir and causing overflow from the reservoir, you have a more serious problem than low coolant. You most likely have a blown head gasket. Especially if it blows coolant from the radiator to the reservoir when cold.

There’s NO coolant in the reservoir. It’s not even to the bottom of the tank. There’s just some of the old, dirty coolant at the top.

This frankly sounds a bit screwy. But no matter. Remove the plastic tank and give it a good cleaning. It should be fairly simple- a bolt or two and a hose clamp.

But early Neons were prone to headgasket failure. Maybe yours hasn’t failed yet, but don’t drive the car until you figure out this coolant situation.

Then I mis-read your original post. I’m not sure how this tank is designed. All the reservoirs I’ve seen are simply tanks with the overflow as a hose nipple at the top, and a cap that lets you see all the way to the bottom. If it is not holding coolant, it is probably cracked and leaking. If the overflow is part of a filler neck, then run a 16 gauge insulated wire down and through as a type of pipe cleaner to see if you can pop the clog.

It just overheeated the other day and we haven’t driven it since. Previously, it drove with no problem. When it did overheat, the temp gauge didn’t register until afterwards (an ominous sign, I’m sure) I stupidly didn’t check the coolant when I bought it, and the dealer obviously didn’t. It’s a nasty brown that obviously hasn’t been changed for a long time. I have an appointment with my mechanic and won’t drive it beforehand. When it did overheat, it left enough sludge in the little tank above the reservoir to block it. I think I’ll just limp it to the mechanic and let him tell me the bad news.