MT Photo

If it's the headgasket, I'm going to flip out so hard.

Och

iTrader: (3)

Ok, my LS400 started overheating a while ago (same engine as the SC), and I first checked for leaks, and as there weren't any apparent leaks, I replaced the thermostat and thermostat o-ring. However after the replacement the thermostat housing started to leak, even though I tightened these bolts pretty damn hard. I had to apply some high temperature red silicone around the housing - its sold at the autozone, pep boys, etc. The leak stopped immediately.

However, replacing the thermostat did not cure the overheating problem. It turned out to be the water pump, and I've spend several weekends replacing it, finally succeeded last week. I'm pretty sure your car is overheating because of the water pump as well, you should replace it, and only use an OEM one. Also, if it was the headgasket, you would be blowing all kinds of smoke from your exaust, your antifreeze would be mixed with oil and vice versa.

MT Photo

No mixed fluids, just rises pretty high in temperature and stays there.

I'll take a picture when I get a change.

Scotty93

has there been any coolant level loss? if so, check for fluid around the head. had a blown head gasket on my Supra, after replacement - took care of the problem. Good luck!

smarshall9

Man did I screw up, I was attempting to tighten up the housing on the thermostat and I broke the bottom bolt to the housing that holds the thermostat.. I called Lexus and the part is not in stock, pirce is $70.. Called Auto Zone they can have it for me tomorrow at noon, price $12.. Should I use the one from Auto Zone or wait for the one from Lexus which can be here by monday.. I think I will also try replacing the water pump... Also is it hard replacing the housing unit...

bigmalik00

12 for the bolt or the housing cover? I think the Autozone part should be fine. Try a junk yard. That cover and bolts are on SC's and LS's....you should be able to find one of the two in a junkyard.

smarshall9

Oh well, I got the leak stopped, but its still over heating. I guess the next step is to replace the water pump.. Is replacing the water pump a do it yourself job or should I seek a professional....

Luke_in_SD

it involves a lot of work, removing front engine cover and timing belt

camberSC

iTrader: (17)

My car just over heated tonight, now I have to check the hoses, radiator for cracks, and so on..... Happy Mother"Fn"s Day to me!!!!!

ihiryu

iTrader: (7)

are you guys sure the fans are even coming on?

camberSC

iTrader: (17)

Okay checked the hoses on sunday, no leaks. Monday, changed the thermostat, radiator cap, and filled up again... Drove around the block, started over heating again, brought it back in, started pulling everything apart and I noticed a leak coming from the corner of the radiator. Started pulling everything apart and when I pulled the fan shroud off, BAM!!!! Bigass crack (maybe 6" long and 1mm wide)....

Started looking for a radiator, got a few quotes, I got a cheap quote from Gazi (thank you) but unfortunately I needed it asap.

Picked up a oem radiator yesterday, installed, filled with orange tang, lol, and we are back in business!!!!

xxtoobsxx

iTrader: (4)

I have the same symptoms. I too had a bigass crack same size right where the uper fan shroud and radiator meet/touch. I replaced the radiator but started leaking water. When the car is moving its fine, if it idles too long it gets hot. Hasn't overheated as i have shut it off before its gets close. But i notice after a good 20 mi drive on the freeway when I shut down get a pool of water under the car comming from the bottom, no apparent leaks elsewhere. So i deduced water pump, not to mention a few guys on here said my initial coolant loss was due to the water weeping through the weep hole! Finaly ordered the parts today! hope to be rockin' soon!!