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The mud-like stuff is most likely oil mixed with the coolant and points to a head gasket failure. While the engine is running the oil pressure is higher than the pressure in the radiator so oil gets forced thru the leak into the coolant.

The real danger comes when the engine is turned off since the pressure "stored" in the radiator can force coolant into the oil. Running with water in the oil can ruin bearings and require a rebuild. If the oil has a coffee color that's what is happening.
 

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Couldn't see the pics as google wants my info for that, but the engine will run well until the gasket blows out more. The mud is an early warning. I'd suggest a compression test with the engine hot.
As I recall you had issues with some kind of an oil cooler a while back. If it was a water-to-oil type it could cause the same symptom.
 

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Discussion Starter #5
Couldn't see the pics as google wants my info for that, but the engine will run well until the gasket blows out more. The mud is an early warning. I'd suggest a compression test with the engine hot.
As I recall you had issues with some kind of an oil cooler a while back. If it was a water-to-oil type it could cause the same symptom.
I placed the photos in this same forum. Regarding the oil cooler situation. I was a performance oil pump that resulted in a piece of Sht.

http://www.rav4world.com/forums/members/albums/21420-mensajero/
 

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Oh yeah it was the oil pump. We'll just forget I mentioned it. :crying

The pics are the exact coffee-color telltale sign of an oil/water mix - 99% of the time caused by a failing head gasket. Won't hurt the cooling system but pumping that mix thru the lubricating system will ruin many critical parts quickly. :egad:Stop driving until fixed unless you plan on a new engine.
 

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Oh yeah it was the oil pump. We'll just forget I mentioned it. :crying

The pics are the exact coffee-color telltale sign of an oil/water mix - 99% of the time caused by a failing head gasket. Won't hurt the cooling system but pumping that mix thru the lubricating system will ruin many critical parts quickly. :egad:Stop driving until fixed unless you plan on a new engine.

In other words, a new head gasket is a must. Or new engine, correct. :wink
 

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In other words, a new head gasket is a must. Or new engine, correct. :wink
Unless it turns out to be a cracked block a new HG will fix it.
 

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I'm going to make a compression check to my engine. How much would a good engine read per cylinder?:confused:
I don't know specific numbers for your engine, maybe someone else will post them, but the variation among the cylinders should be small, maybe 8-10 max.
Another quick test for a failing HG is running the engine in neutral at high revs, say 3000, with the radiator cap off. You should see a few bubbles but not much more air coming out. A bad HG or cracked block will literally turn you radiator into a geyser.
 
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I heard you can also get sludge build up in the cooling system by mixing coolants that don't "play nice" together. This can happen when you mix "cheap green" from local auto store with asian-mfc'd/OEM coolant. Something to consider before you tear your engine apart.
 

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The pic of the dipstick seems quite strange - the oil on the dipstick and most of the dipstick looks clean and even new, while the crosshatch low oil section of the dipstick has what appears to be rust or some sort of gunk in the crosshatches themselves. The pic of the upper radiator filler area appears to show coolant with rust or some sort of material like cooling system sealant - have you used sealant at all? Has the cooling system been flushed several times (remember to have the car heater switch set on full heat so that the heater coil will also be flushed)? Am not certain that you need to take off the cylinder head . . .Agree with Dr. Dyno that you should have a compression check done or do one yourself, before doing anything radical to the engine. Also a cooling system pressure check should be done as well.
 
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I heard you can also get sludge build up in the cooling system by mixing coolants that don't "play nice" together. This can happen when you mix "cheap green" from local auto store with asian-mfc'd/OEM coolant. Something to consider before you tear your engine apart.
Valid point, but I used Preston 50/50. Unless you know of a better one, please by all means, enlighten us with your knowledge.
 

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The pic of the dipstick seems quite strange - the oil on the dipstick and most of the dipstick looks clean and even new, while the crosshatch low oil section of the dipstick has what appears to be rust or some sort of gunk in the crosshatches themselves. The pic of the upper radiator filler area appears to show coolant with rust or some sort of material like cooling system sealant - have you used sealant at all? Has the cooling system been flushed several times (remember to have the car heater switch set on full heat so that the heater coil will also be flushed)? Am not certain that you need to take off the cylinder head . . .Agree with Dr. Dyno that you should have a compression check done or do one yourself, before doing anything radical to the engine. Also a cooling system pressure check should be done as well.
I was also thinking of that. I changed the oil last week. I ran it hard yesterday, but the oil seems fine. I've changes the oil religiously for years. When the changed the clutch in September, and the oil pump. My mechanic said everything was great. Even the oil pan had NOTHING of wear, very clean, it has 100K and then some. I flushed my radiator about a month ago, with Preston Radiator Flush, and NO, I only did it once. Meaning I'm doing it again tomorrow with two maybe three flushes. I'm following this clip. I'll let you guys know what I find. Thanks for the help. Now I have to cancel the Head Gasket order. :wink:nerd
 

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While diagnosing this you want to make absolutely sure there's no water or coolant in the oil. The easiest way to confirm it either way is to drain a sample from the oil pan after the engine sits overnight. Since oil floats on water simply removing the oil drain plug enough to drain some into a clear glass or bottle and then replacing (and tightening) the plug will give you the telltale sample. If it isn't completely oil reorder the head gasket kit and start raising the several hundred USD for the labor to replace it.

PS. For Chris to get water that dirty on his first radiator drain he must have pulled that truck out of a junk yard or someone was running straight water for years & years.
 
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OK, I've already open the hood so tomorrow will be a quick lift on the jack and drain some oil on a transparent container. If it's cool, (after taking a photo of it) I'll just pour it back into the engine. Then do the compression test, and if that's cool. Then I'll do the radiator flushing two or three times to see what we got.
 

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So no signs of water in the oil?

My procedure for a radiator flush is much simpler than Chris Fix's. After draining out the old coolant while the engine is cold I refill with water and the cleaning agent (I use liquid detergent). Run the engine a few minutes with the heater on. Then second drain will have removed most all of the coolant.
After the engine cools I leave the drain petcock open and the radiator cap off. I fill the radiator with my garden hose adjusting it so it just overflows while petcock drains. Now I start the engine and let it run for 15-20 minutes or until the petcock runs completely clear. Once that happens I shut the engine off and let the radiator drain completely. When the engine is cool again close the petcock and fill the radiator with straight antifreeze. Since that's close to half the system's capacity the mix will be near enough to 50/50.
 
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