2000 grand cherokee laredo 4.0 overheating
I added a comment above for things to check - here is what some of the indications mean. If the engine oil is grey or foamy it indicate you have an engine oil/water mixing problem going on - which could mean a blown head gasket, or a cracked block (I've had both problems before). Another indication is when you start the engine cold with the radiator cap off (and the water / radiator fluid at the proper level) you might see bubbles or foam start to flow / move through the water in the radiator. Air is getting injected into the water jacket (again cracked block and or blown head-gasket can cause this) the cooling system is supposed to be a sealed closed pressurized loop. There shouldn't be any "extra" air in the system. A crack in the block or head-gasket leak will allow air (and/or sometimes engine oil) to be injected into the cooling system. Grey / white foam in the oil is water going the other way, from your cooling system into you oil recirculation system. All bad things, somewhere the integrity of those two systems has been compromised . Did your engine ever overheat? that can warp the head and cause a head-gasket leak/ Did you ever have the engine freeze without proper anti-freeze? That could have cracked the block (or inside the head) and allow the water/oil jackets to mix.
Alternatively It could be you just have too much fluid in your radiator. If you look on the side of the water reservoir it has markings for hot and cold levels of fluid. If you have the water level too high when the engine is cold, then run the engine to it's normal operating temperature, the fluid will expand and the "excess" will drain out of the reservoir.
Another thing to check is the bottom hose of the radiator - all of it - is it soft, are there any cracks or holes in it? I had a problem with overheating and leaks - weeks of problems, had the head replaced, the head gasket, a new radiator, the bottom hose looked ok from above but it had a small leak that only opened up when the engine was hot, venting the water, making the water low and causing most of the other problems. Another thing with an old hose even if it doesn't leak is if it is too soft, it can collapse and restrict the flow of water to the engine, which causes the engine to over heat and the water leaking problems.
Check those things - the foam or water in the oil, bubbles in the radiator water when you start the engine cold (just take off the cap and watch it as the engine idles and the fluid is circulating - it shouldn't have a bunch of bubbles or foam), your radiator for obvious leaks (water dripping or squirting out / steam venting out - a small rock could have punctured the core - which can be fixed with a little solder - even "Stop-leak" for a while), and physically get under the vehicle and take the bottom (and the top - which is easier) radiator hose off and look at it look for it being too old and cracked or too squishy - take it into an auto parts place and have them look at it if you are not sure. A $12 hose is a lot cheaper (and easier) to replace than a radiator or a head and head-gasket - this is the voice of experience talking :)
Dec 20, 2011 |
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