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Mud like substance in my Radiator?

6K views 38 replies 9 participants last post by  ALVINATOR 
#1 ·
I've been checking and have already flushed my radiator and I'm finding a mud substance inside it. :confused: I've read on the net that it could be the engine is too cold, a head gasket failure and what not. Any thing guys? :serious
 
#2 ·
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.
 
#4 ·
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.
 
#6 ·
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.
 
#11 · (Edited)
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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#12 ·
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.
 
#13 ·
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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#15 ·
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
 
#16 ·
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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#38 ·
The operating temperature of the oil is usually above the boiling point of water, cooking off the water and leaving other parts of the coolant behind.
If you really want to know what is in your oil, send a sample to Blackstone Labs.

After having mine tested I increased the oil change interval to the 4,500 to 5,000 mile range. Before testing I always did 3,000 mile changes. So they might be saving me some money even giving them $28 dollars every 2 or 3 years. I do get some peace of mind, from getting a clean test report.
 
#17 ·
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.
 
#20 ·
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.
 
#21 ·
Hmmm - Angel, I seem to recall that some kids had sabotaged your RAV in the past - is that correct? If so, is that a possibility for the coolant situation this time, especially if you hadn't locked your RAV while at school?
 
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#22 ·
I think I found the culprit. I was thinking of that. The first time I flushed it, (about a month ago) I did find some mud inside the radiator. I flushed it out with Preston Clean Flush. But looks like it didn't do a good job. Also, at that time, I just ran the flushing ONCE. This time I used 2 Motor Medic by Gunk C1412 10-Minute Radiator Flush, it's Green! I ran it two times, on the second time I took a sample in a glass. I could of drank it. :surprise But there was another culprit. I looked at what I had install, and sure enough, I was looking at it. A TRD Radiator Cap 18.5 psi.

When I changed the Radiator cap, something happen that I didn't listen for a long time. The fan immediately turned on. I didn't hear that fan for quite some time. Regarding the mud, I saw this clip on .

It might be this situation. But I'll finish here and give it a run to see what happens. Like always, I'd like to thank all the member of the forum who chip in with opinions and feed back.:thumbs_up::thumbs_up: You guys are the greatest.
 
#23 ·
So what she's saying is a long neglected cooling system :egad:can produce goo that looks like there's oil in the coolant.
 
#25 ·
Precisely, me too. And why I was alarmed by the "mud" possibly being oil since I assumed our OP friend would have been keeping his maintenance up more religiously.
I am still concerned about the brown/orange material on the dipstick. I certainly hope he did my post 16 test on the oil.
 
#27 ·
Sounds good so far.:smile Keep us up to date! With the mud-like material which was in your cooling system you may need to keep an eye on your coolant pump for leaks since that mud may have caused problems with the pump shaft seal.
 
#29 ·
Following up, my neighbor just lend me a Compression Test kit. Will do it tomorrow and see what the engine says. Following this procedure. BTW, do I have to disconnect the fuel pump? Is their a way to disconnect it from the engine bay? I don't want to mes with the fuel pump. The small of gas will be inside the car for weeks. Yucky

 
#30 ·
I don't know about the 4.1 RAVs but if you can access the spark plug holes without disconnecting anything that is all that you need to do apart from pulling all of the spark plug leads from the spark plugs so that the engine doesn't start while doing the tests.. At this point, if your RAV is running fine, the coolant isn't blowing out of the overflow tube and there isn't any sign coolant in the engine oil then it probably isn't necessary to do a compression check. The other reason for doing a compression check is to determine whether there is combustion leakage via the engine cylinder valves or the piston rings.
 
#32 ·
I just want to see where I'm at with this engine (is it good, or is it worth changing etc). Even though I've hammered it, maintenance was excellent thru out the years. I'll how good tomorrow. I have other plans but I still have to sell an "idea" it to my wife, if you now what I mean. :wink Best part is she doesn't know very much about cars and engine.:wink:wink BTW, mate, what are the numbers that should the gauge read in order for it to be in good condition?
 
#31 ·
I've never disconnected a fuel pump while doing a compression test.
 
#33 ·
I'm not certain what the compression test results should be for your 4.1 RAV, but this is one answer from a post on this forum:

"Spec is about 175 psi. Pass if any one cylinder is more than 15 psi below the others, or if the average is less than 150. Low compression is usually not a problem any more unless there is a bad valve."
 
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