so I have noticed that my coolant is dirty after a change last fall. no biggy, pretty sure its more crud from the lines. I'll change it again and keep an eye on it and life goes on. My oil and ATF look fine. my question is... there's a bit of talk recently about head gasket stuffs and I really don't know what the consequences are. so lets say hypothetically that one has a car with a blown or leaky head gasket. 1. how long does a car continue to run for or is it a catastophic event. 2. what are the symptoms. 3. are there cases where you might consider with an older milage car or for monitary reasons just living with frequent oil changes. I'm just looking for some real entry level information.

thanks folks,
cdt

__________________
2002suzukiGSF600S
1985 190e 2.3

Bad head gasket, how long can I drive it?

Here's a copy and paste from an article I wrote on the Allpar.com web site:

"There are any number of things that'll happen when your blow a head gasket.

Common symptoms:
- Foaming, bubbling, or "gargling" in the radiator.
- Rapid pressure buildup in your cooling system, before the engine has warmed up.
- Some have even reported coolant overflowing from the reservoir bottle because of the pressure.

All these above mentioned symptoms could also be a cracked head. Either way, the head must come off, the gasket replaced, and the head inspected for cracks. At the same time, check both mating surfaces for flatness before putting on a new gasket so you don't have to repeat the job.

Other symptoms of a blown head gasket include:
- White smoke coming from the tailpipe, sometimes intermittently.
- Water in the oil. When they mix, the oil gets a chocolate milkshake appearance.
- Oil in the coolant.
- Cylinder pressure low when using either the wet or dry compression method.
- Cooling system will not hold pressure when statically pressurized.

Look for any combination of these symptoms to diagnose a bad head gasket.

One curious observation of mine, when a person describes their engine problems, and it looks like a blown head gasket, often they mention that the car just had a new radiator put in, or new cooling fan, or some other repair history that suggests the car had a previous episode of serious overheating.

If you had white smoke coming from the tailpipe and your head gasket was bad, chances are the O2 sensor may have been poisoned at the same time. Expect to have problems with it. It may need to be replaced.

Footnote:

One of the bigger challenges for the engineer is to design a head gasket that'll seal an aluminum head to a cast iron block. Aluminum has roughly two times the thermal expansion characteristics of iron. That makes it tougher for the head gasket to maintain a seal with all that thermal cycling than in years past with iron heads. Plus, aluminum heats up faster, thus magnifying this thermal expansion difference between aluminum and iron during warmup. Aluminum heads cannot withstand overheating as iron heads could in the past. It is critical to not let your engine overheat. Overheating is the No. 1 cause of scrapping an engine, not oil neglect as some people believe. Even if you don't blow a head gasket, the head may warp and cause premature wear on the valvetrain components as in some early 4-cylinder Mopar engines from the early 80s."

__________________
95 E320 Cabriolet, 159K

I can tell you what happened when ours was leaky - no water in the crankcase, brown crud floating in the coolant recovery tank. Hoses all deteriorated such that they were 'sweating' (little water droplets coating the outside). I replaced all, and the new upper radiator hose failed in a couple of weeks, leaving my wife roadside.

It took several Tide flushes after the gasket was replaced to keep more brown crud from showing up in the recovery tank. My advice would be to not delay repair.

Steve

__________________
'91 MB 190E 2.3
'08 RAV4 Ltd 3.5
'83 Lazy Daze m'home 5.7