Is this trouble? (Coolant related)

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Joined
May 3, 2010
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Location
Sacramento, CA
While I was changing the oil today, I happened to take a look under the radiator cap, just 'cuz. I found some scum right around the rim of the radiator spout (don't know the real word for it), and when I looked in the overflow reservoir, I noticed some of it on the tubing.

So, the coolant itself is clean clean clean (for information's sake, I had the radiator flushed and refilled at the stealership a few thousand miles ago).

I've read about the dreaded milky coolant, but this just seems to be on the parts (and the fluid is clean). Is this something I should be worried about, or is it just 20yrs of build-up?
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PS - the only maintenance I know for a fact that the PO did was axle-related (i.e., I don't know if the HG's been replaced, or any other major stuff under the hood).
 
Whoa.

That ain't great.

What's the underside of the oil filler cap look like?

Curtis
 
Whoa.

That ain't great.

What's the underside of the oil filler cap look like?

Curtis

Looked fine--no similar scum. And the oil I changed out looked fine (dirty like old oil normally does, but no milkiness).
 
You can get the radiator opening sniffed for HCs by a shop. Was the gunk there before the flush? I'd be shocked if the dealer saw it and didn't recommend a new HG (even if it wasn't needed).

You can also cold start with the cap off and see if you get bubbles (indicating exhaust gas).

If the oil cap is clean and you don't smell antifreeze or have white smoke in the exhaust I'd be incline to think that the HG is ok. You can always have the HG done as PM. My 80 is not exhibiting any signs of HG failure but I will get it done sooner rather than later.
 
Looked fine--no similar scum. And the oil I changed out looked fine (dirty like old oil normally does, but no milkiness).

Mine looked like that when the oil cooler started to weep into the coolant. Never got worse and came back after cleaning. Until I put a 2nd hand cooler in it as mine had a smaller than a pin hole in it that could only be found by sitting it on a bench all cleaned up and full of petrol and left to sit for a day. Then looked for a slight damp spot.
 
You can also cold start with the cap off and see if you get bubbles (indicating exhaust gas).

If the oil cap is clean and you don't smell antifreeze or have white smoke in the exhaust I'd be incline to think that the HG is ok. You can always have the HG done as PM. My 80 is not exhibiting any signs of HG failure but I will get it done sooner rather than later.

I'll try the bubble test. Otherwise, cap is clean, no funny smells or smoke, maybe like tourboy here (below)

Mine looked like that when the oil cooler started to weep into the coolant. Never got worse and came back after cleaning. Until I put a 2nd hand cooler in it as mine had a smaller than a pin hole in it that could only be found by sitting it on a bench all cleaned up and full of petrol and left to sit for a day. Then looked for a slight damp spot.

Iiiinnnteresting...I'll look into that.

As always, thanks all!
 
Maybe its just this terrible monitor, but that looks like the sludge that happens when you mix red with green coolant.
 
I wouldn't read much into it unless you have other symptoms that concern you. The coolant looks clean, it's prolly just a bit of debris.:meh:

I did a gulp recently when I saw a swirl on top of the coolant. It turned out to be from a corroded rivet on the cap.:confused:
 
Maybe its just this terrible monitor, but that looks like the sludge that happens when you mix red with green coolant.

That would make me happy...

I wouldn't read much into it unless you have other symptoms that concern you. The coolant looks clean, it's prolly just a bit of debris.:meh:

I did a gulp recently when I saw a swirl on top of the coolant. It turned out to be from a corroded rivet on the cap.:confused:

Yeah, I think at this point I might just sit on it a bit (no other symptoms I'm aware of--no overheating or anything).

Thanks all
 
What is the stealership doing putting green anti-freeze in Toyotas. When I bought my last gallon from Mr. T (2 months ago), I got the usual RED stuff. Does Mr. T now sell green stuff for their cars?
 
Check this https://forum.ih8mud.com/80-series-tech/413423-92-3fe-oil-contamination.html

I have similar build up under mu valve cover, and my coolant overflow tank is not as clean as it should be.
These two might be related.
Many people here claim that oil coolers migth be one of the sources for this type of contamination.

Personally I got 2 questions:
1. How to test oil cooler and know for sure that it is his fault.
2. These small guys are $$$, so question no.2 is how to get them cheap in good condition?
 
What is the stealership doing putting green anti-freeze in Toyotas. When I bought my last gallon from Mr. T (2 months ago), I got the usual RED stuff. Does Mr. T now sell green stuff for their cars?

I talked to them about that at the time, and they said the red stuff doesn't do so well in the older models. :confused: (that's all I know about that). And I think it had green stuff when I bought it.
 
Check this https://forum.ih8mud.com/80-series-tech/413423-92-3fe-oil-contamination.html

I have similar build up under mu valve cover, and my coolant overflow tank is not as clean as it should be.
These two might be related.
Many people here claim that oil coolers migth be one of the sources for this type of contamination.

Personally I got 2 questions:
1. How to test oil cooler and know for sure that it is his fault.
2. These small guys are $$$, so question no.2 is how to get them cheap in good condition?

Just checked that thread...I'm hoping that's not it (though I've had similar loss of coolant...but that might be what made a puddle in the PS floorboard)...I'll have to check under the valve cover I guess. :hhmm:
 
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I removed my valve cover few times in the past to check how fast this sludge shows up, and it shows up fast. Oil looks good between the changes, and I am loosing coolant (not sure where yet). I removed the cover, changed the oil, drove maybe 100 miles and checked again, and it was there.
But, you don't have to remove the valve cover to check if there is something on the top of it. First remove the oil filler cap and look what is inside it, there should be traces of this yellow/green foam under it, if there is something wrong. I also put my finger thru the oil filler hole and touch the top of the valve cover from the inside, and yes I can feel and see what is left on my finger, oil or mix with coolant/water. Of course engine cold and not running. But your fingers might be bigger than mine.
 
If you have a puddle on the PS floor, that won't requir you looking under the valve cover. You will need to look at things under the dash where the heater core is located. But that puddle could also be coming from a leaking windshield or a clogged roof drain.

What is the condition of your cooling system hoses?
 
...But, you don't have to remove the valve cover to check if there is something on the top of it. First remove the oil filler cap and look what is inside it, there should be traces of this yellow/green foam under it, if there is something wrong. I also put my finger thru the oil filler hole and touch the top of the valve cover from the inside, and yes I can feel and see what is left on my finger, oil or mix with coolant/water. Of course engine cold and not running. But your fingers might be bigger than mine.

Oil cap = clean
Finger in filler hole = oily, but all black (nothing indicating liquid other than oil in there)

If you have a puddle on the PS floor, that won't requir you looking under the valve cover. You will need to look at things under the dash where the heater core is located. But that puddle could also be coming from a leaking windshield or a clogged roof drain.
What is the condition of your cooling system hoses?

As far as I can see, all the hoses in the engine compartment look like they're okay (btw, I think I ruled out the roof drain/windshield leak thing...we had some heavy rains and it stayed dry). That's not to say I don't have a coolant leak somewhere; I just don't see one in the engine compartment.


Edit: Also, bubble test was neg (no bubbles that I saw). But since I wiped off the cap yesterday and drove it around for a bit yesterday evening, there was more build-up on the cap :-/
 
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Have you drained, flushed and refilled the system?
 
I had the stealership do a radiator flush/refill and new thermostat in June.
 

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