Vortec V8 Coolant leak

[ehenry]

I have a 2003 Z71 with a 4.8 Vortec V8. I'm losing coolant somewhere but be danged if i can find where. I've checked the oil and the oil is clear and no oil is coming back in to the cooling system. I can, however, smell coolant when I get out of the truck after coming off the road. I just cant see where its leaking and theres none on the ground under the truck.

Thanks in advance for the help.

 

[Bob_VT]

Re: Vortec V8 Coolant leak

Maybe you have a headgasket leak and you are burning it off through the exhaust. That would create the smell and little (if any) smoke. I would suggest that you pull the spark plugs and examine each one. If you are burning coolant in a cylinder the plug will (should) look differant.

The other possibility is you have a leak in a line that is getting blown away or running elsewhere before it drips. The tiniest bit of coolant will smell like gallons if it hits a hot surface.

Pressure test the system.

 

[dolluper]

Re: Vortec V8 Coolant leak

Heater core maybe,hope it's not your intake gaskets

 

[Caveman Charlie]

Re: Vortec V8 Coolant leak

Oh O. A while back GM came up with a new type of antifreeze called Dexacool. The problem is that if the antifreeze ever gets low then the antifreeze mixes with air somehow and becomes corrosive and eats out all of your frost plugs and such. Terrible, terrible, stuff. Many people have sued GM over it but, they get away with it by saying it's not there fault it's the car owners fault because he let the antifreeze get to low. Lets hope that's not your problem.

 

[TilliamWe]

Re: Vortec V8 Coolant leak

Heater core maybe,hope it's not your intake gaskets

But you know it is. Common problem, big repair bill coming your way. (it was a $600 repair on my 2003 Impala) Get rid of the DeathKill while you're at it. It's bad bad bad bad bad bad stuff. The dealership will tell you that the DexCool doesn't cause the problem, but it doesn't help it. Have the intake gasket replaced and switch to any other brand of antifreeze and you'll be fine.

 

[wncrjb]

Re: Vortec V8 Coolant leak

There should be a "weep" hole on the bottom of the water pump housing. If the water pump shaft seal begins to fail, it will "seep" coolant past the seal and out the "weep" hole. It comes out in such small amounts, it evaporates as it hits the block. That is why you can smell it and not see it.
Every chevy v-8 I had, and if the water pump had some miles on it and was about to go bad, that was the first sign.

I'm not saying that is your problem, but that has been my experience with them.

It's pretty easy to look up from the bottom at the water pump to see any stains on the water pump housing.

just my $.02

wncrjb

 

[Gary H NC]

Re: Vortec V8 Coolant leak

Just went through this a couple months ago on my Vortec V-8
It ended up being the intake gasket where it meets the head on the driver side rear of the engine.Very common on these engines.
Fel-Pro has a new designed gasket set to cure this problem.They are called Perma-Seal gaskets.
Mine started as just a smell after driving then one day it just started pouring anti-freeze.Better get it pressure tested and look real hard with a mirror along the back edge of the intake.The front edge is known to leak also.
I did the repair myself for about 100 bucks...

 

[rogerwa]

Re: Vortec V8 Coolant leak

Just replaced by intake gasket on my 2004 Suburban. I was getting a lean condition on both banks. You might check your codes to see if you are getting a lean condition as well.

Around $500 out the door..

 

[JCF350]

Re: Vortec V8 Coolant leak

More than likely the intake gasket, Pressure test to make sure. This happens on all those engines due to poor gasket design/material. also the heater hose connection on the intake is pretty shaky at best

GM now says to change the Dexcool every 2 years now. Never seen a coolant related problem on properly serviced systems (even with the 5year/150,000 service intervals). Since Dexcool is about the same price as "green" nowdays might as well stay with what's in there.

 

[TilliamWe]

Re: Vortec V8 Coolant leak

So would you say the coolant wasn't properly serviced if the car was 4 years old and had 82,000 miles on it? Sounds like it was in the range you specified, yet it was a brown crudy mess in my radiator and ruined my thermostat, causing the motor to run cold all the time. Had I not corrected the problem, it would have ruined the transmission next.
DexCool is junk! Get it out of there. If you or anyone puts it back in a car... well let's just say a certain line from Forrest Gump comes to mind. Something about being as you do.

But good point about the heater hose JC. Is that one of those "plastic clipped" ones like my 1990 Cavalier had? But i know my sister's 97 Yukon had evaporated coolant all around a hose or two that went to the intake manifold.

 

[dolluper]

Re: Vortec V8 Coolant leak

But you know it is. Common problem, big repair bill coming your way. (it was a $600 repair on my 2003 Impala) Get rid of the DeathKill while you're at it. It's bad bad bad bad bad bad stuff. The dealership will tell you that the DexCool doesn't cause the problem, but it doesn't help it. Have the intake gasket replaced and switch to any other brand of antifreeze and you'll be fine.

Yea but I hate to be the bearer of bad news

 

[SS MAYFLOAT]

Re: Vortec V8 Coolant leak

My boss just had the same problem with his 2005 Chevy. $2600 later and two new heads. He got tired of putting coolant in it and let it overheat. Of course the dealer said that the warranty would not cover it. With the problems he has had with this truck since it was new, I know I will never buy a Chevy truck from 2000 to present.

WIthin the first 10K miles, it had ate off a full set of tires, within 15K the brake pads were gone. At 35K, the dealer put all new rotors/calipers/pads on. Now it has about 65K on it and he has had 4 alignments with the 4th set of tires on it now.

Now, here is the kicker. They bought my service van at the same time as my boss got his truck, a 2005 Express with the 292 V8. I have 48K on it with the original tires and brakes. I have done regular oil changes along with the other filter changes. Knocking on wood right now, but I haven't had any problems with it at all. This van seems to be able to coast all by itself on flat land.

I don't know why or what the problems are caused by, but something just doesn't seem to be right with the truck line. Maybe it was one of those Monday or Friday trucks.

 

[TilliamWe]

Re: Vortec V8 Coolant leak

Yea but I hate to be the bearer of bad news

Good thing for you, I don't mind that job! I'm an insurance auto damage appraiser, so I give bad news all the time!

 

[gss036]

Re: Vortec V8 Coolant leak

I hear you on the Chev trucks, I have a late model 99, Z7 4X4, same as the 2000. They rebuilt the engine at 11000 miles, replaced it w/a factory drop in at 15000 and so far so good, but I don't drive it that much because of the gas mileage, just tow my boat and haul firewood. So currently on about 40K+ on the truck, about 25K on the engine.

 

[Bigprairie1]

Re: Vortec V8 Coolant leak

I heard about this coolant related gasket problem too from a mechanic. He said it was not uncommon on a bunch of the vortecs from that era. I think he said the telltale sign was a burgundy/pink coolant color?
After the usual intake gasket repair they make sure they run better coolant/anti-freeze and that seems to resolve it.
Good luck.
BP

 

[Gary H NC]

Re: Vortec V8 Coolant leak

That quick connect coolant line on the intake is the first place to look.12 bucks for a new one,about 2 minutes to change with a 1 and 1/16th socket.
Most likely the intake though.
My 99 has 96k on it now and the intake gasket was the only major problem its ever had.The inside of the motor still looks new!
So all you Chevy haters can......Oh i better not say!!

 

[Caveman Charlie]

Re: Vortec V8 Coolant leak

My boss just had the same problem with his 2005 Chevy. $2600 later and two new heads. He got tired of putting coolant in it and let it overheat. Of course the dealer said that the warranty would not cover it. With the problems he has had with this truck since it was new, I know I will never buy a Chevy truck from 2000 to present.

WIthin the first 10K miles, it had ate off a full set of tires, within 15K the brake pads were gone. At 35K, the dealer put all new rotors/calipers/pads on. Now it has about 65K on it and he has had 4 alignments with the 4th set of tires on it now.

Now, here is the kicker. They bought my service van at the same time as my boss got his truck, a 2005 Express with the 292 V8. I have 48K on it with the original tires and brakes. I have done regular oil changes along with the other filter changes. Knocking on wood right now, but I haven't had any problems with it at all. This van seems to be able to coast all by itself on flat land.

I don't know why or what the problems are caused by, but something just doesn't seem to be right with the truck line. Maybe it was one of those Monday or Friday trucks.

It sounds like your boos should learn how to drive. If you ride the brakes hard you are going to chew up pads and tires.

 

[JCF350]

Re: Vortec V8 Coolant leak

So would you say the coolant wasn't properly serviced if the car was 4 years old and had 82,000 miles on it? Sounds like it was in the range you specified, yet it was a brown crudy mess in my radiator and ruined my thermostat, causing the motor to run cold all the time. Had I not corrected the problem, it would have ruined the transmission next.
DexCool is junk! Get it out of there. If you or anyone puts it back in a car... well let's just say a certain line from Forrest Gump comes to mind. Something about being as you do.

But good point about the heater hose JC. Is that one of those "plastic clipped" ones like my 1990 Cavalier had? But i know my sister's 97 Yukon had evaporated coolant all around a hose or two that went to the intake manifold.

"http://www.imcool.com/articles/antifreeze-coolant/dexcool-macs2001.php"

 

[TilliamWe]

Re: Vortec V8 Coolant leak

That link is indeed funny. It's all about how they engineered a flawed product, but it's our fault for not jumping through all the hoops that they now say are necesary. I mean come on, "keep the revservoir bottle filled to "Full Hot" even when it's cold"? Then why mark the bottle that way at all? That is the biggest piece of CYA babbling I have ever seen. Fact is the product evaporates, unlike other anitfreeze, and when it gets low it breaks down. They can say "contamination" all they want, but they are the people that put non sealed overflow bottles and the thermostat caps on them to begine with.
I was all ready to just let it go, be done bashing DexCool, but after reading that, I am seriously considering suing them myself. Garbage pure Garbage

 

[TilliamWe]

Re: Vortec V8 Coolant leak

Oh and one more thing, if DexCool doesn't cause the intake manifold leaks on the Vortec engines, how many of you guys have had the ones on you raw water cooled marine engines leak? I had my intake manifold off my 1997 5.7 with over 500 hours on it, and the intake manifold gasket was perfect. I'll bet if it was in a GM truck with DexCool, and had 70,000 miles on it, it would have been leaking.