I've had my Sc300 for about 10 Years now, for some reason i had just replaced her with a New Water Pump, Radiator and Thermostat, and After I started it up.. about 5-10 minutes of just letting it sit.. it felt as if the top tube/hose connected to the radiator and the radiator itself was hotter than usual. This is the second time I had Replaced both the Radiator And the Thermostat and it's still feels too hot. Also today when i had let it sit 5 - 10 minutes and i removed the radiator cap suddenly white smoke was spewing out of the radiator, Sorry for the long paragraph but can anyone please help? It would be very much appreciated, thanx

 

Have you changed the coolant sensor? There's 2. 1 at the bottom part of the radiator, and another at the top of the engine, left front side of the manifold under the wires.

 

Haven't tried that yet but the temperature is fine, im just worried about it being so freakin hot all of a sudden ever since i replaced all those parts and Im worried because i don't wanna have to deal with this stuff later like breakin down on the freeway and having to have my whip towed because of something retarded also I have 2 different thermostats here, The first one i got was from Lexus Dealer it's kinda bigger/taller and i got another one from O'rielly's/Kragen and its kind of a shorter by 2'4's of an inch, I got 168k miles on it still running very strong

 

There also might be air in the system... Make sure you filled your coolant through the refill plug near the thermostat.

 

The Radiators are both brand new also, I poured water into the 2nd one i bought and the water came down freely and after I took out the 1st one i bought and the same method and it goes freely also.. So im guessing it could be the Water Pump or the Faulty Thermostats thats failing ?

 

I even tried that, I poured coolant through the hose next to the radiator cap and the hose behind the waterpump where the thermostat goes in but still its extremely hot.. Can you check the temperature on yours if you can and I will try to diagnose it again tomorrow. thanx man

 

This is what I'm talking about. When you drained the coolant out, this is where you should refill coolant in so that the air in the system would go all out. If there's air in the system it can cause the thermostat to overheat the engine... or something like that. Lol

See that refill plug beside the igniter at the thermostat neck for the lower hose?

 

Alright I'll be sure to check that out tomorrow, also I have a 2Jz. hopefully i don't have a hardtime looking for that but thanx for all the help man.. I'll get back to you tomorrow as soon as possible

 

White smoke sound like head gasket problem

 

Alright king phillip, I finally got it fixed.. thanks bro but now i have another problem.. when i closed my hood and i tried popping it up from the level under the steering wheel for some reason it doesnt wanna open the hood so i grabbed plyers and took off the bottom cover from where the coolant reservoir is and tugged it, and it opened.. but do you know why it wont open from the level under the steering wheel now? Maybe it could be the wire ? Please get back to me, thanks

 

Not too sure what can cause it to not pop open, unless your SC is lowered and the wire is being eaten by the tires... But it does sound like the wire is stuck somewhere. Check if its connected at the hood pop lever?

So what was the problem before?

 

Sometimes the hood latch sticks. just hold the lever open and have someone try to open the hood at the same time. then you can investigate further.

the white smoke also seems to me a blown headgasket. If you have access to a temp gun, see what the actual temp is vetween the two hoses. should be around 170 plus or minus at normal operating temperature. Good luck.