Light chocolate color in plastic coolant reservoir

OHC54

MEMBER
1999 FORD E-SERIES VAN
5.4L
V8
2WD
AUTOMATIC
160,000 MILES

Oil dipstick has no froth, straight oil.
Transmission dipstick pink intermittent appears to have some water.
No water or oil or froth around intake manifold top or side of engine
No exhaust smoking while underway idling or first starting.
Excellent power immediate start reliable.
Believed it to be slight crack or inside gasket leak in radiator
Replaced radiator flushed cooling system replaced auto trans fluid changed oil new zerex antifreeze full strength 3 gallons rest is water.
Seems okay now.

1 Reply

ASEMASTER6371

MECHANIC
52,797 POSTS

Good morning,

This could be the coolant breaking down and showing a rust color. Since you flushed the system, it may be okay.

If it was oil, it would indicate a block failure for the engine. If it was a head gasket, you would have coolant in the oil. The oil cooler, that is, the oil filter mount could also cause this issue. I attached pictures for you of the cooler.It pays 7 hours to replace the cooler. It is a big job since it is so tight in the engine compartment.

I would keep an eye on it to be sure it does not return. The YouTube video below is a similar replacement.

https://www.youtube.com/watch?v=8-nsWMVoE4E

Roy

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