Coolant Level And Over Heating

[bodean]

I have a 1990 ls 400 first started out not heating until i got the rpm's way up.

Now iam starting to over heat, i replaced the thermostat still got the same problem!

I'm a fairly good mechanic but, i have never worked on a lexus, and i have figured out they are a differant breed of car! would someone care to throw a few pointers my way??

thanks, Bodean

[landar]

Its most likely:

A. Low on coolant.

B. Needs air purge, especially after Tstat change.

C. Cap is bad.

There are many (and I do mean MANY) threads dealing with issues such as yours.

Just do a search on "coolant" or "thermostat" and you will have hours of pleasurable reading ;)

For starters, see this thread---> http://us.lexusownersclub.com/forums/index...showtopic=52768

Enjoy!

[don corleone]

what do you mean you got the RPM's way up. were you driving in ECT mode? were you just revving the engine? did the RPM's go into the RED? how high does the temp gauge go? my temp gauge is broken. sorta. it moves within the same range as normal it just starts higher than normal. oddly this happened in the Rocky Top mountains of tenn. it seems that the temp gauge can be fixed by taking out the cluster opening it and pushing the temp gauge down to normal while the engine is cold. could be your prob. like i said the temp gauge stops like it is at half but it's really about 2/3 or 3/4. also you could've broken your water pump. check for leaks. if you did than it's probly time you changed it anyways. my last water pump timing belt combo lasted about 8 yrs and an ungodly amount of miles. i've even heard of LS' going 300k+ on original parts.

[bodean]

just wsnted to say thanks!! this input should get me where i need to b with this issue. i'll let yall know how it turnes out.

thanks again, jeff

[bodean]

just wsnted to say thanks!! this input should get me where i need to b with this issue. i'll let yall know how it turnes out.

thanks again, jeff

[bwilterink]

just wsnted to say thanks!! this input should get me where i need to b with this issue. i'll let yall know how it turnes out.

thanks again, jeff

Yea it seems my coolant is only running through the engine when I gun the engine while I'm driving also my heat only works when I gun it. Could that really be air trapped in the system? How much does an air purge coat and can I do it my self?

[AzHotLS]

Yea it seems my coolant is only running through the engine when I gun the engine while I'm driving also my heat only works when I gun it. Could that really be air trapped in the system? How much does an air purge coat and can I do it my self?

You can do it yourself so the cost is zero. With the engine cool....

1) Remove the tank cap

2) Set heater temp on high (85)

3) Let engine warm up to normal operating temp (to open the thermostat)

4) Rev engine between 2000 and 2500 RPM for 5 minutes (at some point you may see some fluid "blurp" (technical term) out as the air escapes)

5) Turn off engine and let engine cool

6) Add fluid to the tank as coolant is drawn back into radiator (don't let tank get empty)

7) When engine is totally cool, add fluid to full level

8) Replace cap

These are the steps to follow after draining and refilling the radiator.