Radiator??

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TheGuyWho

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So I have a problem…
There is oil mixed in with my coolant (just water). I had this problem before, but I thought I fixed it. Although I'm not positive I did. Im also not positive that I got all the oil out of the system the first time. So now I have two problems. Is the oil mixed in my coolant old or new? Is my radiator bad? the trans oil cooler is inside the radiator, right? Thats the only place where oil and coolant meet, is in the radiator, right? Although my trans fluid level is low, it shows no signs of mixing. Still looks red and new. I just changed my trans fluid out maybe 6 months ago. So, any ideas how I can diagnose the problem? Any ideas how I can flush the system better? I don't want to put a new radiator in (if that what I need) only to have old oil go thru it…
 

stamp11127

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When my radiator failed in my Aerostar it filled the trans with coolant. If the oil the in your cooling system is brown that is engine oil.
I would flush the system a few times with Dawn. Straight water is bad for a cooling system, only use it for testing. If you leave it in your promoting rust and I think it is called galvanic action. Once cleaned if the oil returns and intensifies over time you have a problem.
I would be more concerned with coolant in the oil. If that was originally the case your bearings are probably toast.
 

tonydiv

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I agree, you really do need to check the trans fluid (and engine oil) for signs of moisture.

If you didn't replace the radiator, what exactly did you do to fix the problem?
 
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TheGuyWho

TheGuyWho

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I replaced the radiator, but with another used radiator that I thought was good, then I flushed the entire system twice. I just let it run with the garden hose on drained from radiator, then closed the radiator plug and drained from the block itself. It seemed fine.

From what I can tell my trans is fine. No strawberry milk on the dip stick. Other than being low on fluid. Which is odd because I just flushed it less than 6 months ago. But if there is a leak inside my radiator where oil and coolant are mixing I guess that would explain the coolant being oily and the trans oil level being low??? It smelled like burnt oil inside the coolant reservoir tank too. I wish I could figure out how to pictures on this dang thing... But the car isn't overheating and there is no leaks visible on the ground.
 
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TheGuyWho

TheGuyWho

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When my radiator failed in my Aerostar it filled the trans with coolant. If the oil the in your cooling system is brown that is engine oil.
I would flush the system a few times with Dawn. Straight water is bad for a cooling system, only use it for testing. If you leave it in your promoting rust and I think it is called galvanic action. Once cleaned if the oil returns and intensifies over time you have a problem.
I would be more concerned with coolant in the oil. If that was originally the case your bearings are probably toast.

Which bearings are you referring to?
I am slightly concerned that there is water/coolant in my transmission. That's what I was worried about last time too, but it was fine... Judging by the dip stick I pulled for my trans oil yesterday I didn't see anything out of the ordinary. It seemed to be a normal vibrant red color.
 

IMINYOURCHAIR

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coolant in the oil can cause this on the main bearings.

In that case it was from a buick 3.8v6. it was a pushrod engine and the intake gaskets failed resulting in a coolant to oil mix
 
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TheGuyWho

TheGuyWho

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coolant in the oil can cause this on the main bearings.

In that case it was from a buick 3.8v6. it was a pushrod engine and the intake gaskets failed resulting in a coolant to oil mix

I replaced the intake manifold and the gaskets about 6 months ago. I'm skeptical that's what the problem could be. Seems like I would have more problems if that were the case...right?
 

stamp11127

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If you really want to know if you have a coolant leak, send samples of both the trans fluid and oil out for an analysis. The trucking companies do this all the time, cost should be between $10-$20 each. Google "oil analysis" for companies that provide the service. What you would be looking for in the results is for the presence of silicates (coolant) and in what quantity.
Local trucking companies may also do the testing in house and offer the service.
 
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