Coolant Leak!!!! Help

Echo Echo · December 22, 2002

Hey gang.. I was wondering if anyone has had a problem similar to this:

I keep getting a 'low coolant' indicator on the dash and can smell coolant evaporating when I lift the hood. All the hoses and connections look fine and the overflow tank is fine.

GM Dealership ran a 'pressure test' and says that there is no problem!

I can smell the coolant inside the cab and get the warning light about once a month...

Any advice would be great.. I am thinking that its a head gasket or something like that.

TxDoc · December 22, 2002

Welcome to the forum. Sorry to hear of the annoying problem. I didn't see what year truck you have. I had a 1997 with the plastic radiator tank. I had similar "symptoms". The problem turned out to be a crack in the neck of the tank, just below the radator cap (where the filler neck joins the tank--about 1.5 inches below the cap, itself). I only did this during the night as it cooled and would seal off when it got hot and expanded.

That may not be your same problem, but it may give you something else to look at. Do you notice a small puddle in the morning or at a certain time of the day?

Echo Echo · December 22, 2002

2001 Silverado/Short Bed/Sport Side/Reg Cab..

Thats the odd thing, there is no puddle or visible leaking. I can really smell the coolant near the exhaust manifold on the pass side. I can also hear a gurgle'n noise in the heater core when I drive off from a dead stop.

I may pull the plugs after the holidays and see if there is anything weird there.

Sierra and Jimmy · December 23, 2002

During the Summer months I used to get a Coolant smell outside the truck by the front, but the smell was never inside the cab. But now that u mention that "gurgle" sound, I may have the same problem as u. The "gurgle" seems to be coming from the ac/heater vents at low rpm's, in lower gears. It goes away when I accelerate or when I'm in 3rd or OD.

I don't know, but maybe the problem has something to do with the heater core, or something else on the firewall. But with no visable leaks, I don't know.

I got a huge list for my dealer to do for the 50,000 mile ck up, in January (currently 46,550). The "gurgle" is definately at the top of the list.

Pete

chevroletmb · December 23, 2002

the coolant gurgle is a well known problem at my dealer allthough last time i checked i couldn't find any documentation on it. the problem is a small coolant restrictor just outside the heater core. all it takes is to remove the heater hose and reach inside the heater core with a small pic and pull it out. hope that helps.

BillnSandi · December 23, 2002

I just had the exact same problem on my 2002 Sierra with about 700 miles on it. Definitely had a leak (filled it up twice in a week). Pressure leak test at dealer showed nothing, but I had seen some coolant underneath and beside the heater hoses as they hit the waterpump. They test drove the truck with heater on and off, and sure enough got coolant in the same place. They replaced the hoses, and it seems to have disappeared (only had the truck back for a few days though).

awdvkd · December 23, 2002

I don't know if this applies to the 6.0 liter, but on my 8.1 I had the same smell of antifreeze in the cab and outside under the hood. I never had any leaks on anything on the ground. The dealer couldn't find anything. I kept on getting the low coolant light. One day I got bored and grabbed the flashlight and started looking around. I found that there is a plug on the side of the cylinder head just above the exhaust manifold. It looks just like a pipe thread plug used by a plummer. It was seeping out and dripping on the exhaust manifold. Obviously it was hitting the hot exhaust manifold and evaporating. It took about three full turn to tighten. Haven't smelled anything since. I thought it my be worth mentioning, ggod luck. ???

ShimanoFisherman · December 23, 2002

I'm gonna have to give that a try awdvkd. I've had my light come on a few times, and smelled coolant. But each time, I've killed the engine and restarted it and the light stayed off. Only 5500 miles here.