was wondering if someone could explain to me the symptoms of a blown headgasket? what should i be looking for?

 

depends on how it fails. You could have coolant in your oil (which when churned up starts to look like chocolate milk). You could have coolant leaking into the combustion chambers, which will cause a lot of white smoke out the tail pipe. You could get over-heating when the engine is under a load, because of combustion gases passing into the coolant. USUALLY you will get some sort of coolant loss... but I've seen crazy things. I've seen bad head gaskets leak exhaust out the side of the engine, sounded like an exhaust leak. I heard about a dodge v10 that leaked coolant out the side of the engine. I've seen a few cars leak oil at a bad head gasket.

 

well let me tell you what i have going on and perhaps you can advise. i have an 02 disco ii with around 111k miles on it. i only bought it about 2 months ago. about 2 weeks ago it had overheated and i had to have it towed home. i got it home and took a look at it and noticed the small hose running from the radiator to the reservoir had a hole in it. i fixed the hole filled it with coolant and started it up thinking i had fixed the problem. once the engine warmed up coolant began spraying from around the water pump so i figured that was the cause of the problem. so i replaced that filled with coolant (but not the proper landrover way because i didn't know any better) started her up and everything appeared fine. however, it was running a little rough but i attributed that to it being an old car and not being run for a week, and once the engine warmed up there was no heat coming out of the vents even though the heat was on full blast. so i hopped in and drove down the block to see what would happen. by the time i got to the end of my block it was overheated. so now i'm thinking thermostat with a combination of not bleeding the system properly. i did notice white smoke upon initial startup but it went damn near away by the time it was warmed up. i'm just really hoping its not the head gasket but the more i read the more i'm leaning that way.

 

oh also the oil pressure light came on but didn't come on until it overheated. could this be a result of the overheating?

 

I'd bleed it properly first. No sense worrying if you don't have to. Running it hot can certainly cause the head gasket to fail, so don't drive it if you notice the gauge going hotter than normal until you figure it out. You can pull the dipstick and see if you notice any coolant. Also, you can probably rent a pressure tester and test the cooling system. Do a search, there are some threads here about this kind of stuff.

 

thanks man. i appreciate the advice.

 

Oh... the oil light. I'm not sure. Oil can certainly break down when it gets hot, and an engine will get hot if it gets lubrication problems..... don't run the engine at ALL with the oil light on.

 

An actual head gasket failure in these engines will be either an external coolant leak at either the forward or aft end or a coolant leak into either #1, 2, 7 or 8 cylinder and possibly combustion leak into the coolant system from one of those cylinders. The block to head coolant passages are at the ends and nowhere near the block/head oil galleries. If there is coolant in the oil you've got a big problem, more than just a gasket issue.

If you are seeing white smoke on initial start and no external leak then it's most likely getting into one of the end cylinders. The gasket at the coolant passages is only 1/8th inch wide between either the cylinder wall or the end of the head/block. The spark plug for that cylinder would be cleaner than the others but no matter because you would replace both gaskets anyway so it doesn't matter which bank it is. If you are losing coolant and have no external leaks that's probably the source.

The whole coolant system is overly complex and runs at a higher pressure and temperature than most other vehicles we are familiar with. I think part of it is the cold start by-pass system and some of it might be emissions related but it's prone to leaks if you don't maintain it and keep a good eye on it. It can also be a chore getting all of the air bled out. If you have combustion pressure getting into the coolant system you just better park it and get it fixed immediately. If it's an external leak you can get by with daily top offs for quite some time but watch it carefully because a day will come when the leak will suddenly get much worse because the gasket is breached and the flow from the leak is just like water through a busted levee - it's eroding away faster and faster as time goes by.

 

the white smoke is gone. i think my main problem is getting the air out of the system. i am still not getting heat out of the vents and after the car warms up the oil light comes on which worries me. i'm about to the point where i just need to get it towed into a shop and have a professional repair it. what i thought i would be a routine water pump replacement has a turned into a ****ing nightmare. welcome to the world of land rover right?