Antifreeze/coolant Levels

[wwest]

My wife complained yesterday that she thought she could smell anti-freeze in our 2001 AWD RX300.

So when we got home I checked the coolant level in the expansion tank/reservoir. It was a tad above the "hot" full mark but the interesting thing was that there was moisture visible around the reservoir fill cap, just a little, but enough to be a bit worrisome. Additionally there was a "crusty" surround on the top of the reservoir all the way around the fill cap but at a distance of 1" or so.

IMMHO the "crust" buildup is obviously an indication of a (recent) "history" of coolant overflow

Just went out this morning to check after the engine has cooled all night and the coolant level in the reservoir is still above the "hot" fill mark...

Took the radiator cap off and the coolant level is right at the top in there too.

I have NEVER had/seen any indication of the engine overheating and insofar as I know the coolant system has not been "opened" since leaving the factory in ~2000.

What gives...?

Anyone...?

[lenore]

Is it possible that someone overfilled it? Mine when cold is down at the min mark, and hot moves upward. If it were overfilled it could goe past the max and out the overflow. By the way I think it is time to have it changed. The Antifreeze is only good for 5 years max.....

[wwest]

Is it possible that someone overfilled it? Mine when cold is down at the min mark, and hot moves upward. If it were overfilled it could goe past the max and out the overflow. By the way I think it is time to have it changed. The Antifreeze is only good for 5 years max.....

As I said, I'm pretty sure no one but me has had access. The RX has only been at Lexus once since I bought it new and that one time was because the ABS seemed to be not working.

What is it about anti-freeze that makes you think, believe, it only has a half-life of 5 years?

I didn't change out the factory anti-freeze in my 92 LS400, now at 170,000 miles, until a few years ago, 3 at the most, and only then because it looked a bit murky. Freeze point, specific gravity, and Ph were all still within reasonable range.

[lenore]

Antifreeze is contaminated with metal breakdown, and constant heating and cooling. Though it be a closed system there is still the formation of rust in the engine block.... I am mystified by your increase in coolent unless the radiator is clogging and there is less volume in the radiator for the coolent to flow therefore more in the expansion tank... Only thing I can think of at the moment unless a engine passageway is blocked. Possible there is a overheating condition that the temp gauge is not seeing or your wife didnt notice...good luck West.

[wwest]

Antifreeze is contaminated with metal breakdown, and constant heating and cooling. Though it be a closed system there is still the formation of rust in the engine block.... I am mystified by your increase in coolent unless the radiator is clogging and there is less volume in the radiator for the coolent to flow therefore more in the expansion tank... Only thing I can think of at the moment unless a engine passageway is blocked. Possible there is a overheating condition that the temp gauge is not seeing or your wife didnt notice...good luck West.

A friend suggested that I might have a leak within the ATF cooling section of the radiator and I checked the transaxle ATF level but it seems fine.

Mystified is the operative term.

[lenore]

West, best case scenario your coolent should be replaced at 100k or 5 years. It is possible that its properties for preventing higher temperatures has broke down. Because of this it is expanding when reaching higher temps and causing what you are experiencing. If it were me I would do a coolent change with the non silicate 5 year long life red fluid (toyota or aftermarket) and see if it makes a difference. I know mine is do again, and I am thinking of change hoses as well as the radiator cap. I just read some write ups on coolents, and The Red high life fluid is what was put in our Lexus RX300...

[mikey00]

West, best case scenario your coolent should be replaced at 100k or 5 years. It is possible that its properties for preventing higher temperatures has broke down. Because of this it is expanding when reaching higher temps and causing what you are experiencing. If it were me I would do a coolent change with the non silicate 5 year long life red fluid (toyota or aftermarket) and see if it makes a difference. I know mine is do again, and I am thinking of change hoses as well as the radiator cap. I just read some write ups on coolents, and The Red high life fluid is what was put in our Lexus RX300...

I pretty sure the RX 300 has Toyota Long life red which is good for 30,000 per the manual. My 2000 and 2001 both definetly had this. Toyota now has super long life pink which is good for 100K.

[wwest]

West, best case scenario your coolent should be replaced at 100k or 5 years. It is possible that its properties for preventing higher temperatures has broke down. Because of this it is expanding when reaching higher temps and causing what you are experiencing. If it were me I would do a coolent change with the non silicate 5 year long life red fluid (toyota or aftermarket) and see if it makes a difference. I know mine is do again, and I am thinking of change hoses as well as the radiator cap. I just read some write ups on coolents, and The Red high life fluid is what was put in our Lexus RX300...

I pretty sure the RX 300 has Toyota Long life red which is good for 30,000 per the manual. My 2000 and 2001 both definetly had this. Toyota now has ultra long life pink which is good for 100K.

If I partially fill a bottle with water, heat/cool cycle it daily for a 100 years is it still water?

What components do they put in anti-freeze or coolant that "wears out" or changes chemical composition with long term use?

[mikey00]

West, best case scenario your coolent should be replaced at 100k or 5 years. It is possible that its properties for preventing higher temperatures has broke down. Because of this it is expanding when reaching higher temps and causing what you are experiencing. If it were me I would do a coolent change with the non silicate 5 year long life red fluid (toyota or aftermarket) and see if it makes a difference. I know mine is do again, and I am thinking of change hoses as well as the radiator cap. I just read some write ups on coolents, and The Red high life fluid is what was put in our Lexus RX300...

I pretty sure the RX 300 has Toyota Long life red which is good for 30,000 per the manual. My 2000 and 2001 both definetly had this. Toyota now has ultra long life pink which is good for 100K.

If I partially fill a bottle with water, heat/cool cycle it daily for a 100 years is it still water?

What components do they put in anti-freeze or coolant that "wears out" or changes chemical composition with long term use?

Don't know, don't care. Maybe it's not a chemical wearing out but some other reason the change is required. I am just quoting what Lexus, Toyota and other companies claim. I stopped using the Toyota stuff when it got up around $20 a gallon. I get Prestone from Walmart for about $6/gallon so a coolant change is fairly inexpensive insurance.

[wwest]

West, best case scenario your coolent should be replaced at 100k or 5 years. It is possible that its properties for preventing higher temperatures has broke down. Because of this it is expanding when reaching higher temps and causing what you are experiencing. If it were me I would do a coolent change with the non silicate 5 year long life red fluid (toyota or aftermarket) and see if it makes a difference. I know mine is do again, and I am thinking of change hoses as well as the radiator cap. I just read some write ups on coolents, and The Red high life fluid is what was put in our Lexus RX300...

I pretty sure the RX 300 has Toyota Long life red which is good for 30,000 per the manual. My 2000 and 2001 both definetly had this. Toyota now has ultra long life pink which is good for 100K.

If I partially fill a bottle with water, heat/cool cycle it daily for a 100 years is it still water?

What components do they put in anti-freeze or coolant that "wears out" or changes chemical composition with long term use?

Don't know, don't care. Maybe it's not a chemical wearing out but some other reason the change is required. I am just quoting what Lexus, Toyota and other companies claim. I stopped using the Toyota stuff when it got up around $20 a gallon. I get Prestone from Walmart for about $6/gallon so a coolant change is fairly inexpensive insurance.

But along with a coolant drain and fill comes the possibility of a vapor lock/"air pocket" being left somewhere in the hoses or engine and not long after your engine is TOAST...!

[mikey00]

West, best case scenario your coolent should be replaced at 100k or 5 years. It is possible that its properties for preventing higher temperatures has broke down. Because of this it is expanding when reaching higher temps and causing what you are experiencing. If it were me I would do a coolent change with the non silicate 5 year long life red fluid (toyota or aftermarket) and see if it makes a difference. I know mine is do again, and I am thinking of change hoses as well as the radiator cap. I just read some write ups on coolents, and The Red high life fluid is what was put in our Lexus RX300...

I pretty sure the RX 300 has Toyota Long life red which is good for 30,000 per the manual. My 2000 and 2001 both definetly had this. Toyota now has ultra long life pink which is good for 100K.

If I partially fill a bottle with water, heat/cool cycle it daily for a 100 years is it still water?

What components do they put in anti-freeze or coolant that "wears out" or changes chemical composition with long term use?

Don't know, don't care. Maybe it's not a chemical wearing out but some other reason the change is required. I am just quoting what Lexus, Toyota and other companies claim. I stopped using the Toyota stuff when it got up around $20 a gallon. I get Prestone from Walmart for about $6/gallon so a coolant change is fairly inexpensive insurance.

But along with a coolant drain and fill comes the possibility of a vapor lock/"air pocket" being left somewhere in the hoses or engine and not long after your engine is TOAST...!

I have been doing coolant changes for 40 years on my private vehicles without toasting any engines. I have also never heard of this happening to anyone or discussed on any forums but I guess anything is possible. You may have a greater chance of getting get hit by lightening after a coolant change.

[mehullica]

I'm sure the "crust" is just water vapor that carries a little coolant in vapor form to vent out the reservoir and deposit on the cap area. The liquified grease in the coolant that lubes the seals on the waterpump will wear out at times, Ph, freeze points etc, are still ok, but the grease is gone after a few years.