Hey there
I guess I'm the newest dude on the block here. Have had my 92 LS for a few months and have been browsing CL long before that, but never got around to signing up. But here I am!!

My question is to due with my Cooland level. Whenever I fill it to the recommended level (between the black lines on the res.) it overflows when the car gets warmed up. After a week of driving, the coolant is only filling a quarter of the res when cool. Gauge on the dash always reads the same normal temp weather it's freezing out or hot and humide......and on highway or city.
Any Ideas???

 

Welcome to the Lexus family.

Check your oil, if it looks like chocolate milk it is bad news.
If that is okay, replace the radiator cap as these are relatively inexpensive. Any signs of leakage from the radiator itself?

 

TooPhat,

Welcome to CL! Regarding the radiator, the lines in the reservoir are deceiving on this series. I have a 91 LS and I made the mistake of trying to keep it at the upper line or close to it. It overflowed every time. My advice is to only trust the line when it is completely cool (at least 1/2 day of not being used) and then check it. Only add if below the lower line. Since I started doing it that way about a year ago, it has been fine. Haven't had to add any in a very long time. Yours probably overflows out of the top of the reservoir, right? Very common problem on these cars. You can fix it with some adhesive or replace the reservoir if it bugs you. I just clean it off whenever I wash the car if needed, it seeps a little bit from time to time, but nothing major.

Also, the temp should be about the same irregardless of outside conditions. That is the thermostat doing its job. Maximum fuel economy and performance is achieved when the temperature stays in a narrow range. Other cars I have had have had a much wider range, but my Lexus always stays under 1/2 way no matter the outside temp, a/c or no a/c, etc.

 

Thankfully I've never had the chocolately milk syndrom. But for future reference...what does this mean....I've guessing blown seals or gaskets eh? And no there's no rad leakage. When it's full it leaks where the top part of the res joins the bottom half.

I think GA400 hit the issue on the spot. Sounds like you've had the same problems as me and I'll try your advice. Thankx everyone

 

The chocolate milk syndrome means that you have probably blown a head gasket which means that your oil & water have mixed.

 

I'm going to have bad dreams and nightmare's of chocolate milk.

 

Hopefully, you won't ever have water mixing with oil or oil mixing with water. You will know by examining the coolant or the engine oil.

When looking at the coolant, it will have drops of oil floating around in it.

However, If you have coolant mixing with the oil, you will have chocolate milk......

Jeff