93 civic ex coupe. everything is pretty much stock.

my car over pressurizes and the water steams out of the reservoir.
no leaks in the hoses, and the radiator seems to be okay, nothing blocking it.
i've changed the termostat, and bled the system. and i've noticed that it only does it when i'm still for too long, (e.i. stuck in traffic, doesn't matter if its cold outside or hot.)

sometimes it'll go for days without it happening. i've been putting water now because coolent gets expensive, but it still did it when i've had coolent. it just started doing this recently. the motor feels strong, so i don't really know what's up.


can anyone help me out here?
thanks everyone!

 

is your fan even working? and it could be meny things water pum head gasget warped head. check these things

 

pretty much the same thing is happening to me. i had to keep adding water in the reservoir like you. i changed the thermostat and radiator and when i try and let the fan cycle with the cap off, water starts to shoot out of the top even before the fan turns on. i changed the relay. and temporarily hooked the fan up straight to the battery and it still does it. so i'm thinkin its not the fan. what else could it be. i don't want to change the water pump until i know for sure what it is.

 

yeah mrharmonic, fan is okay. i dont want to change the water pump until i'm sure also. how do i check if its bad? also how do i know if my head gasket is warped? there's no oil in the water.

 

Blown head gasket, it ain't too bad to change.

 

Water steaming out of your radiator is a bad head gasket? Hopefully none of you work at auto shops...

Is there any ethelyne glycol in your radiator now or is it just water?
Is your radiator cracked?
Is it the stock, plastic radiator?

More info needed.

 

water is steaming out of the reservoir, not the radiator itself. its just water, no more coolant. the radiator seems to be fine, it does not leak. there are no leaks in my cooling system (other than the over pressurizing.) it is the stock radiator that comes with the ex.

 

had this problem before in my ITR when I re did the head gasket and used new studs. Basically your head gasket is probably leaking into one of the coolant passages. Pull the head and get some used studs... if you do not get used and buy new make sure you re-torque them cause they do stretch. I would just buy used and torque them once and call it a day.

Best of luck!

 

Dude, half the reason why your car is over heating is because you're using water.

You need the green stuff called, "ethylene glycol" in your radiator to increase the boiling point of the water in the coolant.

http://en.wikipedia.org/wiki/Ethylene_glycol

Flush all that tap water out of your radiator, fill it up with a proper mix of distilled water and antifreeze (I recommend 80% water, 20% antifreeze), bleed your radiator properly and let us know how it goes.

 

i agree with Koopa Troopa, get good coolant in it . two major things that turn good hondas bad: neglecting the oil and neglecting the coolant. skimping on a few bucks worth of fluids can end up costing you big bucks when that engine needs replacing.

i don't think it's "over pressurizing" though (maybe not possible with stock water pump) i think it's boiling over/over heating. you said it happens when you're sitting still... i say check that fan! you can jump the two pin connector for the water temp sensor to confirm good wiring and fan motor. to check the sensor the car needs to be started and run untill it heats up and the fan cuts on.

as for the jumping to conclusions about head gasket failure... sure excessive coolant in the overflow can be a side effect of combustion gasses leaking into the coolant, but it should be checked to confirm it's headgasket before jumping into the job. check for bubbles in the coolant, test for presence of CO2 with detector...

 

I've personally seen a couple that had no other symptoms. Car ran fine, didn't overheat. No coolant in the oil, no oil in the coolant.

 

i stand corrected, thanks. i edited my post, hopefully to more accurately convey my point.

 

use 50 50 80 20 is much and a little expensiv.

 

nvm i saw it was 80 water 20 anti lol thats good lol

 

I'm telling you it's a blown head gasket, get a new one and some new studs, preferably arp's and it will be fixed, I would put money on it.

 

hey guys, i think its the fan. haha

seems to not be working.