- I have a 2001 Lexus es300 automatic with 246,000 miles .
seems that coolant tank is overflowing and engine is overheating. The fans won’t even turn on sometimes. I was thinking it had to do with the cooling system. I have changed the radiator cap, thermostat, water pump and done a coolant flush. I’ve ordered a new radiator which is on its way. Engine was running very healthy. A friend mentioned me it might be a blown head gasket, I was doubting him but I could be wrong. Any tips or advice?
It's easy to gather information on the head gasket. Scotty has a video on that procedure: https://www.youtube.com/watch?v=v0U8Iyf0kk4
I also suspected a head gasket leak in my 22 year old Ranger, as I was losing coolant with no obvious leaks. There was also milky oil on my oil filler cap.
When you do Scotty's test, make sure you drop the coolant a good inch or two in the radiator. You will get a false positive when the thermostat opens if you don't get enough out. I tried the test and my gut sank when it turned yellow, but the level also rose in the tester, so I tried again after siphoning more coolant out. 30 minutes later, my test stayed negative.
I figured out I had two problems, the radiator cap wasn't properly grabbing and latching onto the filler neck, and the shop I paid $250 to replace valve cover gaskets didn't put my PCV valve back in the valve cover, thus the milky stuff on the cap. I slowly worked the radiator cap on, got it to grab, and haven't lost any coolant in 6 weeks.
More obvious head gasket problem signs are milky oil, white exhaust, and spark plugs that look like they've been steam cleaned. Usually you can smell burned coolant in the exhaust. I had none of these symptoms, other than the milky stuff on the oil cap.
