Coolant frustration: new thermostat installed wrong way?

seabun · 2017-07-05T21:55:28+00:00

Try to keep exposition short as I can Driving to San Antonio from OK, engine overheating. Once in SA, Alamo Toyota tells me: 1. radiator is leaking (cheapy aftermarket put in 2-3 yrs ago in a pinch) 2. intake manifold gasket is leaking (gasket to thermostat?) 2 days, $$ later, I get: 1) new radiator (16410-AZ011, OEM but says Denso?) 2) water inlet gasket (16325-62010) 3) thermostat (90916-03075) 4) 1 gal of toyota red coolant (assuming they mixed it w/ water so actually put in 2 gal) Back on road, turn on Torque app and while driving at night, no A/C, temp is hovering around 205°, and idlng in driveway it reaches 208°. That seems too high. When it was overheating on drive down, it was getting into 225°+. Research on here says most of you see temps around 190°, maybe closer to 200° on hot days with the A/C blasting. I've also read a bunch about Thermostat jiggle valve placement. Consensus says to clock it at 6, or downward. My copy of the FSM confirms this. I check with Alamo and they tell me the new thermostat was installed at 12 and is supposed to be at 12. WTH!? Please somebody help me out. Our Thermostats are supposed to be set at 6, right? Do diff years have different specs? (Mine is a 1999). Should I take it back in and make sure they flip the Thermostat around before I head back to Oklahoma, which I was planning on doing tomorrow, or say F-it and just do it myself when I get back home? On an otherwise pain-free ownership, coolant issues on this 4R have been my achilles heel. It makes one of the best things about owning one, roadtrips and excursions, an anxiety-ridden struggle bc I fear anytime I hit the highway I will, like this trip, get stuck midway. Maybe the last thermostat I had, which was also installed at Alamo a yr ago btw, was also clocked at 12?? In conclusion, Radiator+thermostat+gasket are brand new, water pump+timing belt are 1yr old...truck should be ready to ride for many miles (just hit 190k)...but not if it overheats. Will flipping the thermostat ease my worried mind?? Thanks for any and all thoughts!!:usa2:

Thread starter seabun
Start date Jul 5, 2017

TheDurk

Elite Member

Aug 8, 2017

verbutani said:
Would you recommend factory 12 o'clock for the 3RZ-FE based on your ten years' experience here?

FSM recommends up to 15° on either side of aligning the valve with the "protrusion of the water inlet housing" (appears to be roughly one o'clock--I just checked.) I've never seen anyone recommend anything different, but there is not that much 4 cyl discussion.