1JZ H2O Temp rose kinda high!

[suprastanger507mgte]

Hi guys/gals,

This has happened on a few occasions around the same area.

Took car for a drive and its temperature started spiking high going uphill - not a very long uphill drive.
It did it for most of my trip, so I pulled over,let it kool,and drive was without any incident except the needle was pointing above the half mark.
On my way back, I was boosting heavy and hit the same hill which is a lot longer and steeper when returning.Doing about 80mph most of the way.Weather had cooled down by now.
Gauge was pointing to normal reading all the way

Hydro fan setup and no coolant leaks.

When I pulled over, the reservoir had fluid ABOVE the "FULL" mark and I know that the radiator was full and reservoir was at the "FULL" mark exactly.
When I opened the radiator, I could not see any antifreeze but the reservoir was full to the top so I guess it pushed it back and was not able to suck it back in.
I filled the radiator and it only too about a liter of water.
Changed the radiator cap when I got to my destination with a new 13lbs cap.

My questions are :
What would cause the radiator not to suck antifreeze from the overflow?

How do I test to see if my Hydro fan is working properly as opposed to just spinning which I see it do when my engine is running?

Any help/insight would be much appreciated.
Thanks.
MOe.

 

[92SupraMan]

FYI my 1j runs at about 190-200F and I have a 6 mile grade that I go up almost everyday that makes the temp rise to about 210F. Was still at 210 the other day when it was 99deg outside.

Keep in mind that the 1j does run a little hot because of the oil cooler and the twins. I have read that an external oil cooler works well for keeping it a little cooler and it also helps the oil.

I would get a real temp gauge at least for summer so you dont have to depend on the slow response from the stock one.

I thing you would know if something is wrong with the Hydro fan, because mine is capable of sucking up misc road debris and small animals. Check your fan fluid and make sure your using the recommended ATF.

 

[suprastanger507mgte]

FYI my 1j runs at about 190-200F and I have a 6 mile grade that I go up almost everyday that makes the temp rise to about 210F. Was still at 210 the other day when it was 99deg outside.

Keep in mind that the 1j does run a little hot because of the oil cooler and the twins. I have read that an external oil cooler works well for keeping it a little cooler and it also helps the oil.

I would get a real temp gauge at least for summer so you dont have to depend on the slow response from the stock one.

I thing you would know if something is wrong with the Hydro fan, because mine is capable of sucking up misc road debris and small animals. Check your fan fluid and make sure your using the recommended ATF.

Thanks for the input. Is your fan loud enough to be heard from the inside or outside of car>
I think it maybe my fan is just spinning at a constant speed and I don't recall it being audible at all eventhough I see it spinning.
Maybe the Fan ECU is bad?

 

[92SupraMan]

All I know is that you can feel the fan pushing air out the sides of the hood and yeah, its kinda loud. Make sure you have the temp sensors wired up correctly.

 

[suprastanger507mgte]

hhhmmmmm I was just home and Unplugged the Hydro fan ecu , and did not see aany change in the fan speed, it just kep at the smae speed...and Ive never had felt the fan blow as strongly as u describe...

Thanks man, I may have a bad ecu for the fan or may the sensor in the radiator is bad...or wiring..i'll check it out..

 

[92SupraMan]

No problem, Btw when I upplug my ECU there's a major difference in speed.

 

[suprastanger507mgte]

Well , I was able to fix this problem today , and WOW!!!! what a difference the fan makes.

I tried another Solenoid but that did not help.
I looked in the reservoir and the fluid was not circulating so I thought it could be the actual pump.
Today, I decided to go the cheapest route possible and took a good look at the wiring and everything "seemed" okay, but I needed to doublecheck.
Printed out the fan's electrical circuit for the sensor and ecu and found out I was missing two important wires from my plug.

One I traced from the sensor on the radiator ( Green wire ) and the other one was the Yellow/red wire on the solenoid itself.
Found them hangin around the harness - lol
Plugged them into the plug for the fan ecu according to wiring diagram and the freaking fan fired right up to speed.
I am elated.

Thank you guys for your help on this. It made me check things I could have missed.