Overheating not even hot, apparently

[Morsolo]

Hey guys,

(Boring back story coming up... Skip this paragraph if you're not interested )

Recently stumbled across this site, an amazing resource. I've been browsing around, getting some info for my Accord. 1992 Aerodeck, it's pretty run down, but it was a gift from my brother for getting my license. I originally hated the thing... But after having it for 6 months or so, I've come to really like it... It has over half-a-million KMs on the clock (approx 312k Miles), so it's really done the hard yards, but man does this thing keep on going!

I'll get some pics today. With her peeling paint job and everything.

Anyway, getting to the actual question, recently the car has started to overheat. The car used to go through radiator coolant pretty quick, now it's using it very slowly. Some reading around on here lead me to believe it might be a busted Thermostat. Also, interestingly, the temperature gauge only ever says the engine gets about half hot, never into the red (I know this isn't the case under the hood, does a broken Thermo affect the reading of the gauge?)

I'd love some opinions here, I'm hoping it is the Thermo, cause it's cheap and easy.

[HATCHing]

Well.. you can also check the temp sensor's contact connection. Make sure it isn't loose or corrod.

[DIRTY DAVE]

a bad thermostat can cause it to over heat weather its stuck open or closed. stuck closed will cause you to not have a constant coolant flow. stuck open allows the coolant to ALWAYS flow. a thermostat is designed to open and close while vehicle is running. if its always open, it doesnt allow the coolant to stay in the radiator long enough to dissipate heat therefore you will see a increase in temp while sitting at idle for to long for instance at a red light or a drive thru. however a bad thermostat is not going to give you a false temp reading to my knowledge. i would think that would be caused by a bad temp sensor. there are 2 of them, one is on the head right under the distributor and the other is on the coolant neck for the upper radiator hose at the head.

[Morsolo]

Alright, I'm guessing the Thermostat is stuck closed, or half-way or something. (Probably not open). Either way, I'll test and replace that

As for the temp gauge, ah, I didn't even know there were sensors for it (I know, sorta makes sense that there should be... haha). But I'll check those out too, will report back later today.

Thanks guys, quick replies

[YOanthony]

Small possibility, but you may have a small split in on of your hoses. Happened in my old CB mate, my gauge inside stayed the same, but then under the hot it was hot as hell under the bonnet. So give your hoses a good looking over and make sure none of them have a split and are leaking. Apart from that, yes, try checking the thermostat!

[Flatline]

already said, but the thermostat only opens to allow flow. the temp sensor actually runs the gauge in the car and runs the relay for your cooling fan.

if you looking coolant, look at the usual suspects. Check you coolant/oil for signs of the other fluid (head gasket issue)

go over ALL of you coolant lines. that means the rad hoses, the coolant bypass lines, the IACV line, the FITV lines if those are still hooked up, etc. any of those could be cracking of even fraying at the end allowing just a tiny bit of coolant out at a time.

also check your radiator cap. if its not holding pressure it'll let coolant out into the overflow. If the rad is old it could be clogged and cause a build up of pressure that can cause the lines to break.

not too hard really, should only take an hour or so to track down the problem if you go through everything one by one.

[B l A z Ee]

a bad thermostat can cause it to over heat weather its stuck open or closed. stuck closed will cause you to not have a constant coolant flow. stuck open allows the coolant to ALWAYS flow. a thermostat is designed to open and close while vehicle is running. if its always open, it doesnt allow the coolant to stay in the radiator long enough to dissipate heat therefore you will see a increase in temp while sitting at idle for to long for instance at a red light or a drive thru. however a bad thermostat is not going to give you a false temp reading to my knowledge. i would think that would be caused by a bad temp sensor. there are 2 of them, one is on the head right under the distributor and the other is on the coolant neck for the upper radiator hose at the head.

Thanks bro this helped me out i been having this issue for awile now i havent been able to figure it out =]