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Milky coolant

2K views 22 replies 8 participants last post by  Wayneg 
#1 ·
I have an 05 with about 158,000 miles on it. The other day I was in a fast food drive thru and could smell coolant, looked down and noticed engine temp climbing. I shut it off before the temp gauge reached the red mark. Got out and saw that it was spilling out milky coolant from the overflow tank. I'm assuming it's oil mixing with the coolant and I blew a head gasket. Is there and other places that a seal could let go and allow oil and coolant to mix? I appreciate any insight on the matter, thank you.
 
#3 ·
05 is known for bad Denso radiators. That in time allowed coolant to mix with ATF. Hopefully coolant hasn’t found it’s way into the transmission.
But yes, a blown head gasket can mix engine oil with coolant.
Check oil and transmission for contamination.
 
#4 ·
05 is known for bad Denso radiators. That in time allowed coolant to mix with ATF. Hopefully coolant hasn’t found it’s way into the transmission.
But yes, a blown head gasket can mix engine oil with coolant.
Check oil and transmission for contamination.
Had my oil changed on Thursday last week. This happened Friday. Today the oil on the dipstick showed no signs of contamination. I'll check the transmission fluid in the morning.
 
#9 ·
You guys posted my most fearsome pics.:oops: Guess I'll have to settle for posting a mild-mannered photo of the difference between the OEM Denso radiator and the new & improved one, where to get one, and how to replace it.



Wood Motor vehicle Automotive tire Bumper Asphalt
 

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#11 ·
#14 · (Edited)
This is all I could get off the ATF dipstick.
I’m not seeing any hint of red on that rag. That, the tranny fluid level being low, and the tan mixture in the coolant overflow reservoir aren’t looking too hopeful. What color is the coolant in the radiator?
 
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#15 ·
I’m not seeing any hint of red on that rag. That, the tenant fluid level being low, and the tan mixture in the coolant overflow reservoir aren’t looking too hopeful. What color is the coolant in the radiator?
I’m holding out with a little hope that if it is ATF mixing in the coolant, that it pumped out of the transmission and not back in.
 
#17 ·
Looks like whatever is in the overflow reservoir is also in the radiator. That makes sense. I’d still want to know what that substance is and find out why the tranny fluid level was so low.

Other observation is there is non-OEM coolant in the system. Honda coolant is blue.
 
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#18 ·
ATF in the coolant can be overcome. Just don’t want coolant in the transmission. It can do serious damaged. As stated, since ATF is unmeasurable on the dipstick, hopefully it pumped out into the radiator break, but didn’t draw back in. The ATF needs multiple drain and fills as soon as possible. That would require the radiator, radiator hoses, ATF lines to the radiator be replaced. A flush of the coolant system need to be performed. Something that won’t harm the system but would remove the residual ATF (Do not use tap water).
 
#19 ·
If your vehicle were mine, I’d disconnect the ATF lines to the radiator, create a loop bypassing the radiator. Drain out old ATF and fill with Valvoline MaxLife ATF. This would allow me to drain the block and old radiator and use distilled water and a coolant flush product (someone suggested dawn dishwashing liquid to clean out ATF). Continue to do multiple flushes until clear. Replace radiator and hoses. Then add the appropriate coolant compatible for Hondas. 50/50 mix. Reattach ATF lines after multiple drain and fills of the ATF.
 
#23 ·
I have an 05 with about 158,000 miles on it. The other day I was in a fast food drive thru and could smell coolant, looked down and noticed engine temp climbing. I shut it off before the temp gauge reached the red mark. Got out and saw that it was spilling out milky coolant from the overflow tank. I'm assuming it's oil mixing with the coolant and I blew a head gasket. Is there and other places that a seal could let go and allow oil and coolant to mix? I appreciate any insight on the matter, thank you.

I had that also, wound up being a cracked block and dropped in a new engine in my 15 with 110,000.
 
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