Coolant issues

[HPF Chrisk]

Most of you will see the topic title and think this is another person ranting on about how there rb overheats, well actually i have the oppisite problem. I have a rb25 swaped s13 with a koyo radiator and 2 10 inch pusher fans. Heres my prob

If i disconect both fans while driving the car gets up to 170 degress, if i do any spirited driving and or high way pulls it will get to 168 and lower. But if the car idles it will get up to 196 max with no fans on. so at this point i have the fans coming on at 185 but the problem is the car never gets this warm and so its idle never kicks down and its in warm up mode all the time or something because while crusing the air fuels are any where from 11.9 to 12.8 and i am going throug a tank of gas every 4 days or so. The gas mileage does not bother me that much but i would like the car to idle down. I do have a fmic to and i figured that would make the car run a bit hotter due to less air flow but it does not.

Currently the car has no bumper on it but tonight i am going to try to mount my bumper and see if that changes anything to do with the temps but i dont think it will cause i had my bumper on for about with the same problems listed above. I dont know what water pump or thermostate are in the car because i did not change them when i did the swap. I took it apart and the water pump looked fine and it said it had just been changed when i got the motor. I also never took the oil pump off and changed it or the timing belt or tensionrs. I am going to do all of this this spring but now i am worring about the short crank problem (not sure if i have this) and dont want to have to tear the bottom end apart to fix it if i do have a short crank snout. Any ideas on my coolant issue would be great. Thanks in advance and sorry for the huge post

[Joe]

i dont remember what the "warm" temp for the RB is but i think its lower than 170.

have you verified output of your ECT sensor? if its bad it can always read cold (totally seperate sensor than your cluster sensor fyi)

[HPF Chrisk]

i have not verified the output of the sensor, i can do that today to. but last summer i put a new one in. I am reading the temps off of a aem water temp gage and the sensor is located in the top radiator hose.

[Joe]

i would definitely at LEAST verify the voltage of the sensor. check it when cold, and as the car idles/warms up. it should obviously show a resistance change as engine temps change (i dont have the numbers, sorry. check the FSM)

[240z4u]

My car did that when the T-stat was not seated perfectly, leaked water around it. Car would get downright cold after highway driving.

Evan

[ANVIL]

sounds like the tstat is stuck open. try replacing it since you didnt do it initially.

[HPF Chrisk]

i dont think the t stat is stuck open because the car comes up to 170 degress and sticks quickly. it warms up fast, i still have not been able to check the sensor voltage, will try to do tonight