Blown head gasket, how does this happen? - Jaguar 2005 S-TYPE 4.2L V8

Hey Michael,
How/why do you think you have a blown gasket/cracked head??
....If you have a blown head gasket/cracked head you need to get it fixed ASAP.. Check your oil for cross contamination...( a light cream colored oil indicates water/antifreeze mixed with the oil).this WILL cause major damage if you continue to run the engine..(WATER is NOT a good engine lubricant!!!!) There are several "sealants" or radiator stop leak products... BUT ..cleaning these out of a coolant system is a NOT FUN!!.. Sorry.. trying to "patch" this will lead to more $$$$$ down the road!!

Well if you keep driving on a blown head gasket, one of many things could happen.
1. The engine's cylinder heads will eventually get so overheated they will warp (aluminum will do that). When that happens you are going to have to replace the engine altogether.

2. The rods will get thrown and cause seriously internal damage to the engine. In extreme cases can cause a fire and explosion.

3. Your engine could seize up from overheating due to damaged piston rings, burned and bent valves, etc...

In short nothing good will come of driving with a blown head gasket.
Get it fixed ASAP.

To replace a blown head gasket requires a lot of labor on this vehicle. Its a v6, meaning you have 2 head gaskets to replace instead of just 1. It requires removing air cleaner, disconnecting battery, removing most of the accessories that are belt driven, removing the intake manifold, egr valve and tubing, exhaust manifold on both sides of engine, timing belt removal, valve covers, and a few smaller items. After removing everything on top of the engine, you'll have access to the cylinder head bolts. Removing them will allow you to lift off the cylinder heads. Before replacing the gaskets, you must send them to a machine shop to have the gasket surface milled true flat again. They must also be inspected for cracks (which will sometimes happen with blown head gaskets) which would render them useless.
If this is a vehicle you really like, perhaps consider investing in a quality used motor. Its less labor intensive, less repeat repair, and you may come out saving a few bucks.

SOUNDS LIKE THE THERMASTAT!!

A blown head gasket or a large air pocket in your coolant system. Have a block check done to see if your head gasket is blown

So the first question is ... is it really a blown head gasket? Could also be damaged head, block, etc and the timing chain can wear through it's housing and allow coolant into the oil. If it is a blown head gasket then why did it happen? Is the head warped, coolant passages corroded, or ?? Here's link to
a '93 manual to give you some idea what you're dealing with. http://personal.utulsa.edu/~nathan-buchanan/93fsm/ Can you replace the gasket in shop or driveway ... depends on what sort of
complications you run in to. You may want to have a valve job done while you're there, maybe
time to do the timing chain, etc. Give it a try.

Often (but not always), a blown head gasket will also cause deposit of water on a piece of cardboard held an inch from the tailpipe output while the engine is running (when this is happening, it is likely that the catalytic converter has been ruined and the muffler will corrode in short order as well).

Sometimes drops of water will be seen dropping from the end of the tailpipe. Another clue: turn on the heater; often when the head gasket is blown an odor of antifreeze and synthetic rubber will emanate from the heater vents.
Many of the symptoms of blown head gasket can be caused by some other problem in the cooling system, without the head gasket being damaged. Conversely, other problems with the cooling system can cause a blown head gasket and/or warped head.

When checking for a blown head gasket, one of the most common tell-tale signs is a milky-gray ring around your oil cap. When coolant enters the engine oil through a crack in the head or through a blown gasket, it evaporates and leaves a milky ring around the oil cap. Another easy way to tell is to check your oil dipstick. Change your oil and pull out the dipstick. Make sure that you take note of how far up the dipstick the oil is. Top off your cooling system and fill your cooling reservoir to the top. Screw radiator cap back on and start engine. Run engine for about 20-30 mins. or until it reaches normal operating temperature. Allow engine to cool (engine must cool completely to get accurate oil reading!!). Check oil dipstick again. If the oil has a watery appearance and has risen noticeably up the dipstick, the you probably have a blown head gasket or a warped head. Also look for a dripping, sweet-smelling liquid coming out of your tailpipe. Any of the above symptoms could be the result of a blown head gasket. The easiest way to tell is with a compression meter. This replaces the spark plug and lets you know what compression each cylinder is running at. If your compression is abnormally low, then you have a blown head gasket or a warped head. (note: consult repair manual for appropriate compression of each cylinder.)

Water/Antifreeze in the exhaust, and usually a cloud of white smoke, is indicative of a blown head gasket or cracked. This usually happens when the vehicle overheats due to a bad thermostat; the head gasket usually blows first and can sometimes crack the head.
Blown head gasket - 350 to 400 to repair; cracked head, add 200 to 300 dollars.

Mike...

Cylinder head gasket starting to go possibly. Check sparkplugs for fluid and or rust.

Could be a blown Head gasket or cracked head. Should be a drain at the bottom of the radiator I think on the drivers side. You will need to pull the heads off and have them checked Magnifluxed for cracks. If they find none then install new head gaskets and see what happens. I have the torque specs for your head bolts if you need them. Let me know.