Questions and Answers

Saturn Overheats Q. I have a 1993 Saturn SL2 that appears to have a cooling problem. I bought the car *new* from a Saturn dealership in 1993.

Anyway, when I moved to Arizona in 1997, the engine started to rapidly heat up when in slow or standing traffic. I replaced the water pump, hoses, temperature sensor, thermostat, and serpentine belt. I flushed the engine three times with both powder-type and liquid-type flush concentrates. Those things seemed to alleviate the problem (it still heated up, but not as fast), and I eventually had the radiator "cored." Up to this point, I had not changed the coolant.

This past summer, (while still in AZ) the engine started to lose coolant. I traced it to a crack in the plastic portion of the radiator assembly (called a "tank" I guess, although it is not a reservoir or anything). So I decided to replace the radiator.

I bought a new radiator from a radiator sales company - it turned out to be copper rather than the OEM aluminum type. After I installed it, it developed a small leak from the plastic-to-metal interface (where the metal tabs clamp the plastic part). So I dumped in a container of Alumiseal - leak stopped.

While I was changing the radiator, I bought a new belt from Checker Auto Parts. It took 2 hours to get the belt on (normally a 10 minute job) and the following day the belt disintegrated while driving on the highway! It was (obviously) too tight, but it also turned out to be about 1/16th of an inch too wide. I immediately replaced the shredded belt with one purchased at the Saturn dealership.

About 3 weeks ago, I drove from AZ to Maryland - with no problems (of course, since the highway speeds pushed plenty of air through the radiator!).

So I'm driving around yesterday (in Maryland), and BOOM! The plastic portion of the new radiator pops off the metal core. Hhmmm. I brought the radiator to a repair shop and they're fixing it now. But the boss of the shop thinks there might be something else wrong... like a bad head gasket or something? Help!

Thanks,
Dave

A. A bad head gasket or cracked head is a definite possibility here. It can be checked in a couple of ways. The cooling system can be tested for exhaust emissions with a special chemical tester or the cylinders can be pumped up with compressed air to see if any air bubbles are visible in the cooling system.

The wrong belt wouldn't harm the water pump, but that's not to say it couldn't be bad. Over time the fins inside the pump deteriorate and don't push coolant well enough to keep the engine cool.

The water pump is cheap and easy enough to replace and that would eliminate it as a possibility. But I think a bad head gasket or cracked head is the more likely problem. "Normal" overheating would not blow radiators apart