TOOK THE DEX COOL PLUNGE

[lucerne06]

On a previous post, I said that I was losing coolant(dexcool) in my 2006 Lucerne with a 3.8 L . It would use about 4 oz every few months(14-16 oz) for the entire year., which I would top back up to the FULL COLD line. Anyway, I decided to take the car to my authorized buick dealer and let them TEST and CHECK the system for leaks. Here is what they told me and printed out on my invoice.

CHECKED FOR LEAKS..NONE FOUND..ALL HOSES AND CONNECTIONS OK...NO STAINS ON ENGINE TO SHOW COOLANT LEAK..COOLANT RECOVERY TANK SHOULD BE TOPPED OFF WITH DEXCOOL EVERY TIME CAR IS SERVICED...WE DO NOTICE WITH DEXCOOL THAT THE LEVEL IN THE TANK DROPS...POSSIBLE WATER EVAPORATION FROM THE COOLANT IN THE RECOVERY TANK.

so what do you guys think? I had them drain,flush and refill the system with new dexcool, just to make sure, it cost me 120.00 total.

 

[pbm]

I don't believe in 'water evaporation from the coolant in the recovery tank'. I think you have another GM engine with faulty gaskets.

 

[lucerne06]

Well I also am spectical, so over the past year I had two used oil analysis done on my oil changes, and both analysis of the oil said NO COOLANT in oil.

SO I am hoping that here someone with an understanding of engines,coolants, etc who actually work on and see these things on a daily basis...can give me some answers instead of just opionions, however I will take all opionions be it good or bad..Thanks

 

[George7941]

I have had my truck for over three years and the Dexcool level never goes down.

Dexcool gets blamed for everything, now for excessive evaporation!

 

[ZGRider]

Originally Posted By: pbm
I don't believe in 'water evaporation from the coolant in the recovery tank'. I think you have another GM engine with faulty gaskets.


Or maybe a GM with faulty Dexcool that ruins gaskets??? Chicken or egg?

That coolant has to go somewhere and if it isn't leaking outside the engine then it is leaking into the engine. It is possible the HG is leaking and it is being burned in the combustion chamber, but not getting into the oil. Not likely. Even though the used oil analysis say no internal leakage, and the dealer says no external leakage -- it is leaking somewhere. Look under the car every morning, feel the front carpets, check the oil filler cap for white sludge, and check a sparkplug for burned coolant, it will look splotchy colored not uniform tan or dark brown. Open the hood after driving and smell for coolant -- it smells kinda sweet.

Also, reach under the water pump and feel for coolant from the weep hole.

 

[Moose016]

Originally Posted By: George7941
Dexcool gets blamed for everything, now for excessive evaporation!


Dexcool is the cause of global warming. It also shot Kennedy.

 

[ZGRider]

Ahh, and the Dexcool saga goes on ...................... to be continued....

 

[Stu_Rock]

Does this car have a pressurized recovery tank?

I have the Lucerne's predecessor, a 2005 Park Avenue, and its tank has a vented cap. On most drives, the car splashes a little coolant out that vent.

I doubt there's a gasket incompatibility problem in an '06. Slime may become an issue for you, though. I had it in mine, and my mother had some in her '05 LeSabre.

 

[lucerne06]

It is the non pressurized system...I never see,smell, etc any coolant drops, drips, etc..ever...and believe me this is bugging me and I check almost on a daily basis when car is hot and cold, driven far or short , and search for any leak or a sign of a leak..It's really baffles me..

 

[bullwinkle]

Pump it up with a pressure tester (AutoZone & others will let you rent/borrow one for free), look for leaks-if the pressure drops & NO leaks are visible-that's when it's time to start worrying (unless you're still under warranty!). Another head gasket leakage indicator is RAPID buildup of cooling system pressure on a cold start (before the coolant has a chance to expand thermally). I love my pressure tester-had it over 20 years, hasn't been wrong yet!!

 

[onion]

I even heard once that Dexcool is poisonous if you drink it. And yet it looks JUST LIKE Koolaid.

 

[TurboLuver]

Originally Posted By: onion
I even heard once that Dexcool is poisonous if you drink it. And yet it looks JUST LIKE Koolaid.

I'll let one of the pro dexcool guy's on here disprove that one!

 

[Stu_Rock]

Originally Posted By: lucerne06
It is the non pressurized system...I never see,smell, etc any coolant drops, drips, etc..ever...and believe me this is bugging me and I check almost on a daily basis when car is hot and cold, driven far or short , and search for any leak or a sign of a leak..It's really baffles me..

I am never able to smell it, but if I pop the hood after a drive, I usually find a drop or two coming off the tank cap.

If your used oil analysis indicate no coolant in the oil and the cooling system holds pressure, then I would say that you have either evaporation or a small leak in the unpressurized side.

You might be able to use a refractometer to identify evaporation by looking for an increase in ethylene glycol concentration.

 

[lucerne06]

They said they pressure tested it and found NO PROBLEMS..I am considering taking to another dealer for a second opionion.

 

[wapacz]

A uv dye pack for coolant?

 

[lucerne06]

if they do put a dye pack in, does it affect the coolant or anything else in a negative way?

 

[KrisZ]

There is one little trick that you can do for HG leak check if you suspect coolant leakage into the cylinders.

When the engine is absolutley cold, start the car, put it in drive and while applying brakes, put the rev's to 2000rpm, keep it like that far a minute. Shut the car off, go and open the radiator cap, if there is pressure and coolant starts flowing out of the fill hole, you have a gasket leak, if no coolant comes out you're OK.

 

[UNC038]

I believe GM switched to the aluminum intake gaskets by that point, so it's most likely not the intake, head gaskets are also rare on the 3.8. I vote for evaporation and/or bad sealing cap. It doesn't take much to lose a couple ounce.

 

[John_K]

Originally Posted By: Moose016
Originally Posted By: George7941
Dexcool gets blamed for everything, now for excessive evaporation!


Dexcool is the cause of global warming. It also shot Kennedy.


The cause of the current recession? Descool!

John

 

[lucerne06]

Radiator cap and system were pressure tested, both were said to be OK. No stains or signs of leakage anywhere to be found on the engine,ground,radiator, nowhere...I have always susspected evaporation..as it does lose more coolant in the summer then winter months..however...
Is anyone else out there with a 3.8L 2006 or newer GM engine having the same situation occur?