I have about 500 miles on car and the yellow coolant for the engine is not a bright and new looking as the intercoolers. It is turning a dirty yellow/brown look. Is this normal?
Yellow Coolant not as Yellow?
- Thread starter Will's97
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I'm far from an expert, but that doesn't sound good to me. I'd take it to the dealer and insist they flush the radiator under warranty. If the new coolant turns dark, too, I'd start worrying.
Caveat: I've got the old green coolant in my Cobra, and I'm not familiar with this new yellow stuff. Maybe it's normal for it to darken, but if that were the case I would expect the intercooler fluid to do the same...
Caveat: I've got the old green coolant in my Cobra, and I'm not familiar with this new yellow stuff. Maybe it's normal for it to darken, but if that were the case I would expect the intercooler fluid to do the same...
I have the standard green stuff in both the radiator and intercooler. Yellow? Did you maybe end up with a winter package?
Neither the green nor the yellow are "regular" coolants - both are reformulated with lower silicates.
The Yellow is the advanced G5 formulation developed in Europe by BASF for premium manufacturers like M-B, Audi etc. Technically, it is a HOAT, tradenamed Glysantin. It is phosphate free. The main benefits of phosphate free coolants are:
(1) Cosmetics: Hard water reacts with phosphates in coolant to form scale deposits in overflow bottles. These deposits could form in other parts of the cooling system, causing blockage and overheating (see next part).
(2) Corrosion: Phosphates tend to aggravate any corrosion that might already be present with any aluminum parts in the cooling system. Aluminum Phosphate is formed, which is insoluble in the ethylene glycol solution of the coolant. The aluminum phosphate will tend to settle out in the cooler areas of the cooling system, causing blockage. This can cause overheating of the engine, which will accelerate the aluminum corrosion. In other words, the corrosion will tend to feed on itself until damage is done to the engine or the coolant is replaced (refreshing the inhibitors).
Premium Gold is a long life, low silicate formula that is extra good as an anti-corrosive, yet easy on soft metal impellers, head gaskets, aluminum heads, etc. Had my car come with green, i would have switched over to the Premium Gold as Ford calls it. Ford does not recommend converting, likely because techs will not want to take the time to flush all the old stuff out first.
http://www.imcool.com/articles/antifreeze-coolant/G05-Glysantin.htm
Neither is compatible with the Orange coolants so do not think of mixing them. Do not mix the green and yellow either.
The browning - well it does appear darker in my reservoir also, but I wrote that off as just some residue from mfg. Also, I know GM often adds those brown anti-leak pellets on the line, and it is possible Ford does the same. As long as it is not oily, I would not fret over it, but if it continues to darken, definitely have it checked.
The Yellow is the advanced G5 formulation developed in Europe by BASF for premium manufacturers like M-B, Audi etc. Technically, it is a HOAT, tradenamed Glysantin. It is phosphate free. The main benefits of phosphate free coolants are:
(1) Cosmetics: Hard water reacts with phosphates in coolant to form scale deposits in overflow bottles. These deposits could form in other parts of the cooling system, causing blockage and overheating (see next part).
(2) Corrosion: Phosphates tend to aggravate any corrosion that might already be present with any aluminum parts in the cooling system. Aluminum Phosphate is formed, which is insoluble in the ethylene glycol solution of the coolant. The aluminum phosphate will tend to settle out in the cooler areas of the cooling system, causing blockage. This can cause overheating of the engine, which will accelerate the aluminum corrosion. In other words, the corrosion will tend to feed on itself until damage is done to the engine or the coolant is replaced (refreshing the inhibitors).
Premium Gold is a long life, low silicate formula that is extra good as an anti-corrosive, yet easy on soft metal impellers, head gaskets, aluminum heads, etc. Had my car come with green, i would have switched over to the Premium Gold as Ford calls it. Ford does not recommend converting, likely because techs will not want to take the time to flush all the old stuff out first.
http://www.imcool.com/articles/antifreeze-coolant/G05-Glysantin.htm
Neither is compatible with the Orange coolants so do not think of mixing them. Do not mix the green and yellow either.
The browning - well it does appear darker in my reservoir also, but I wrote that off as just some residue from mfg. Also, I know GM often adds those brown anti-leak pellets on the line, and it is possible Ford does the same. As long as it is not oily, I would not fret over it, but if it continues to darken, definitely have it checked.
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I have been watching for any oil and have found none. Thanks for the info and keep you posted after more miles are put on the engine.
I noticed the same thing on my car. It has ~1,200 miles on it, and it overflowed yesterday. Cleaned it up. Took the car out and beat the hell out of it. Got home, and no overflow. Strange...
Oh yea, My radiator coolant is yellow/brown also. I don't want to take it to the dealer unless it's a matter of life and death.
Anyone have a car with the yellow coolant that's still yellow (in the radiator overflow)??
Anyone have a car with the yellow coolant that's still yellow (in the radiator overflow)??
Mine turned orange...course that was after I dumped in the red Water Wetter. 
Mine was built June, 10th and now has 4K on it. My coolant has also turned a brownish color. No cooling problems, no overflows even in the 105+ degree summer heat of July and August. It was starting to bother me, but now sounds "normal". If it gets any darker I may take it in though.
Originally posted by mosconiac
Mine turned orange...course that was after I dumped in the red Water Wetter.
Hahahha me too i did that today!
OK. Cool.
I guess the later cars have the yelow turned to brown stuff. Mine was built in July...
I guess the later cars have the yelow turned to brown stuff. Mine was built in July...
My car is an July 02 car. This is an old thread...........I guess since this has reapeared that it seem to be working as designed. My car now has 6,000 miles and it never got any darker.
It is normal, as you have determined.
There is a TSB out for discolored coolant. Brought my car in for various things and the coolant discoloration is normal. The TSB was put out to inform people that the discoloration is normal.
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