2JZ Radiator Flow?

[love ke70]

Linden, if you read, and read properly you would understand.

The issue was that when the HOT coolant from the top of radiator got to the thermostat the radiator had cooled it soo much that it would shut the thermostat, thus causing the coolant in the engine to get hotter and hotter.

Anywho... Ive ripped the guts out of an old thermstat and threw it in. Surprise surprise it now runs at around 82°. Cold start doesnt last long, about 2 minutes, then the coolant temp is up to 40°, go for a casual drive for 5 minutes and its up to 72°. Start giving it a bit, stop and then idle and the highest it got to was 90° then it came back down to 82° very quickly. Ive let it idle for 10 minutes and it stayed right at 82°. Drove at 70kph and it was 76° and stayed there. 100kph it dropped to 72°.

So from the anaylsis its simple. The thermostat i had was set to open too late in the temp range. I need to either find another low temp thermostat, 70° or similar, or leave the current set-up in place (which id rather not).

Anyway, im off to jamboree!

Big thanks to all that helped, oldcorollas, you are the man
Ben

linden, what is the issue?

sbyder, i had a similar issue in my 1g ke70, no reason for it to be overheating but it was. went from a 89 to a 82 thermostat and the problem is fine now. it was either getting heat soaked and couldnt drop the temps, which i doubt, or like you said, not opening because of the watet coming back to it.
hope you can sort your problem
if you take the thermostat with you, into whatever automotice store and see what they list in that design but of a colder range.

g/l with it

[CrUZida]

Thermostat is in the correct way, ive triple checked that as well as testing it and it opens at 82 degrees like its meant to and opens all the way to 8-9mm at 100 degrees.

Thermostat should be fully open within ~10degrees of setting.

If its taking 20degrees to open fully then its faulty.

[cambelt]

Well just a note the JZ thermostats are bypass thermostats and i dont think they make a lower temp version,
Dave

[Dieseltrain]

The TRD Thermostat is a 70something temp thermostat for 1JZ engines... Available from toyota.

[sbyder]

Sard and a few others also make 68° thermostats. Just gotta wait on shipping from japan unless i can find a local dealer.