I drive my car for like 5 min and the temp stock temp guage is almost at H. if i keep moving it doesn’t get too high but still high. when it is around H, the lower rad hose is perfectly cold and the rad is just slightly warm. i can touch it with no problem. however, my overflow is boiling.
to me this means either the thermostat isn’t opening or there is an air bubble in the water pump. is this correct to assume or can anyone think of anything else it might be?
Wait, that doesn’t make sense…
Isn’t the overflow reservoir piped out of the rad?
Could the rad be partially blocked by deposits? :dunno:
yes. thats the part that doesn’t make sense to me either. the thing is, the overflow is controlled by the rad cap. it will only release into the overflow once the rad had reached a certain pressure. maybe thats just the normal temperature of the rad when its hot that i felt.
buy a new rad cap and test the thermostat in a pot of boiling water with a thermometer.
be sure the thermostat is seated properly in the housing so it doesnt crack when you try and tighten it up again
if thermostat isnt fully open its time for a new one, just throw one in your pocket in a junkyard and be done.
get a new rad cap and t stat… and bleed the system…
run the car with the rad cap off untill the car comes up to normal temp
wait untill the t stat opens and let the coolant bubble untill it stops bubbling over (that measn all air shoudl be gone)
shut the car off.
top up coolant
replace rad cap and drive.
that SHOULD fix your problem
it did with mine… only thing i had issues with is that the fc has 2 rad caps due to the placement of the upper rad hose… other than that same same.
GT
hey bro, don’t drive your car man, a simpe over heating problem can turn into a nightware, fix your junk now before it’s too late (it may already be too late)
and I’m talking about cracked head gasket / other damages. I had the same problem with my '89 honda, only I didn’t fix it 'cause I’m budget racing, next thing you know head gasket is cracked and now my over heating problem is beyond just replacing $10 parts.
faaack 
eric, do what greg says, BUT when burping the system, elivate the front of the car, so that the rad IS garenteed to be the highestpoint of the coolant system, this will cause any air trapped in to evacuate the lines.
it’s as simple as parkin on a hill.
hey i just had this issue and posted up on on how to fix the issue as i go along lol…
the problem can be the thermostat and the rad cap. When then resovoir is over flowing that means your rad cap isnt keeping the pressure in the system soo its a cheap fix. Id say get a rad cap and drive it and see how it goes if you dont have much time to work on your car. If its fixed then great… if it still has an issue then go for the thermo and bleed your rad system and refill.
I changed the thermo but i still had an issue… i changed the rad cap and it worked properly ever since for the last week or 2… So id say get a rad cap for now.
hes just lazy
i told him t odo this 10 times already
so i raised up the front and refilled the system and then let it bubble with the rad cap off. the thermostat didn’t even open. them got up to normal operating temperature and the heat just started to seap back to the rad through the top rad hose into the rad. the bottom rad hose was stone cold but the coolant was boiling out of the top of the rad. to me this says thermostat. its brand new from CTC so i dunno why its not working. i went to nissan but they didn’t have any in stock. i guess ill go get another ctc special. 160* should be fine?
mm interesting my car does the samething but it takes much longer to
get really hot i had my overflow filled to the top one time…
160 is to low for the winter, and cars run better around 180-195.
minimum run a 180 if you ask me.
eric did u remove ur clutch fan?