Expert: Roland Finston - 12/5/2011

Question
Hey Kevin, I was talking with Roland, and this is where we were--
Question:

QUESTION: Hi Kevin, I have a 2002 Sebring, 3.0L V6. It has been running hot, and the radiator cracked a couple weeks ago. I swapped that out, and then it started overflowing into and from the coolant reservoir. I changed the thermostat this morning thinking that may have been shot, but the problem continues. I'm really hoping it's not the head gasket. Any help would be greatly appreciated.

ANSWER: Hi Tom,
Some signs of a head gasket leak would be excess white smoke coming from the exhaust when first starting the engine the next morning after it had been driven. Milky color/foamy oil in the crankcase. Rapid onset of coolant overflow when first starting the engine. Early sounds of bubbling from the engine, shortly after starting. Radiator shops have a sensor to detect exhaust gas coming out of the colant reservoir, another sigh of a head gasket leak.
If any of these are present it would be suspicious that one or the other head gaskets is leaking. If that is the case you would want to find out which gasket is leaking by checking for wet spark plugs in all 6 plug holes. About the only stop gap would be try some Bar's leak in the cooling system. If that doesn't seal the leak, then it is sometimes effective to loosen the head bolts on the cylinder bank that is leaking about half a turn, and then retighten the bolts to the specified torque level and pattern using a torque wrench, on the possiblity that the leak is due to loose bolts rather than a torn gasket.
Let me know how you dind the situation to be after checking these out.
Roland
PS Sorry for the delay but I just found yuor question in the pool to which itt had been referred by Kevin.

---------- FOLLOW-UP ----------

QUESTION: Thanks for responding Roland, It fills the reservoir after driving for a few, and now is stalling when I am at a stop, no problems while driving, but once it warms up, it stalls everytime I stop. Not sure if it's a separate problem or not. Getting frustrated now, because it stopped overflowing for a day or two, and then started again with the stalling.



Answer:

Hi Tom,
Have you looked for the other tell-tale signs I listed besides loss of coolant from the reservoir?
You could also ask a radiator shop to check for the presence of exhaust gases in the overflow bottle which is solid proof of a head gasket leak.
The stalling can be caused by the presence of coolant in the intake manifold or combustion chamber which is another sign of a head gasket leak.
Roland   

I didn't even think to ask if it could be the water pump? No milky or foamy oil, and no more smoke than usual when starting it in 30 degree weather. The bottom hose from the radiator isn't even warm to the touch while the rest of the system is scolding hot.

Answer
Hi Tom,
If the bottom hose is cold, the top hose is hot, and yet you have a new radiator and thermostat then indeed the water pump impeller may have come loose or been otherwise damaged. I would believe that if there is good reason to believe that the new radiator has good fluw through, it points to the lack of effective pumping action. The only other possibility is that the thermostat is not inserted into the housing with the flange parallel to the casting wall and the air vent facing the front of the engine. So you might want to check that before getting into the water pump change-out job that unfortunately requires removal of the timing belt. Of course that belt may be nearing the mileage that would suggest it be changed out anyway. If there are sounds of crackling coming from the engine that could be an obstruction in the internal water passageways but that is unlikely.
Roland
PS Kevin forwarded your question the 'pool' where I just found it.