How do i check the source of my car overheat?

**joseph_abri** · October 10th, 2010 01:40 PM

how do i check the source of my car's overheat problem, its a chevy optra... here: the temperature rises up to almost 3/4 or even higher of the temp gauge... even with a bit short distances. it is gulping water every trip. it just happened a couple of days ago, both fans (auxiliary and radiator) working, replaced the auxiliary fan lately, and the thermostat... there is extreme steam pressure in the upper radiator, its hotter than the other hose, based from my touch, (this is where the thermostat is located), a day ago, there was steam coming out of the radiator reserve cap, replaced the cap now its ok, when i replaced the aux fan yesterday i removed and returned the upper rad hose connecting to the radiator, and clamped it, perhaps the clamp is not sealed enough as of today i can feel the steam pressure escaping from the hose that is connected to the radiator, might come back to the mechanic who put them yesteday to tighten the clamp... but i am not sure if that solves it, because there is still the overheat problem to think of,. how do i solve it...

the rad months ago was replaced along with the aux fan and thermostat not more than 3 months ago, with chevy service center, if it continues heating the engine it might destroy the engine so i wanna pinpoint the problem.. and diagnose it correctly, i dont like the idea of replacing everything, just to make it work... if one can diagnose where is the source, well be answering the problem right on..

**joseph_abri** · October 10th, 2010 01:52 PM

if i put the aircon heater at the hottest temp, the temperature goes back to its normal below half level... but without it, lets say i put a cool airconditioner, it goes high, or when there is none, as well but a bit slower

**desert fox** · October 10th, 2010 04:28 PM

Baka Cylinder head gasket na problema ng kotse mo bro....

**jick.cejoco** · October 10th, 2010 08:03 PM

Originally Posted by joseph_abri

how do i check the source of my car's overheat problem, its a chevy optra... here: the temperature rises up to almost 3/4 or even higher of the temp gauge... even with a bit short distances. it is gulping water every trip. it just happened a couple of days ago, both fans (auxiliary and radiator) working, replaced the auxiliary fan lately, and the thermostat... there is extreme steam pressure in the upper radiator, its hotter than the other hose, based from my touch, (this is where the thermostat is located), a day ago, there was steam coming out of the radiator reserve cap, replaced the cap now its ok, when i replaced the aux fan yesterday i removed and returned the upper rad hose connecting to the radiator, and clamped it, perhaps the clamp is not sealed enough as of today i can feel the steam pressure escaping from the hose that is connected to the radiator, might come back to the mechanic who put them yesteday to tighten the clamp... but i am not sure if that solves it, because there is still the overheat problem to think of,. how do i solve it...

the rad months ago was replaced along with the aux fan and thermostat not more than 3 months ago, with chevy service center, if it continues heating the engine it might destroy the engine so i wanna pinpoint the problem.. and diagnose it correctly, i dont like the idea of replacing everything, just to make it work... if one can diagnose where is the source, well be answering the problem right on..

have a pressure check on your cooling system. seems like you guessed all the way through and yet the problem persists. with a system pressure check, any and all minor leaks appear. if your system can not hold and maintain pressure, it will overheat

**joseph_abri** · October 10th, 2010 10:12 PM

bakit kaya ganun pag nilagay ko sa full ung aircon tapos naka heater mode... me hot at cold kasi ung aircon ko, biglang bumababa ung temperature, as in super bilis, bumabalik sa normal..

sabi ng kuya ko, sabi daw ng mekaniko ng nissan (para sa serena nya) at toyota (para sa vios nya) e pwede daw tanggalin ung thermostat.. wala ng thermostat un daw kadalasan rason ng overheat kasi nag stuck up at di nagbubukas ung themostat.... kaya alisin na daw kasi di naman tyo cold weather at tropical tyo so di na kailangan un, kailangan lang daw un sa mga nagfrefreeze ung oil, and water sa lamig... para mabilis uminit, sa pinas di na daw.. totoo ba to.. alisin ko?

eto pa.. kakapalit lang sa kasa ng thermostat... sa chevrolet. aug 25 alam ko meron ata nitong 3 month warranty... kasama kaya to .. palitan kaya nila.. baka sabihin lang nila iba cause ng sira palitan ito, ito, at ito baka mapamahal pa ko sobra..

at ano ba ung nabasa ko dito na thermostat switch? san un, meron ba ang optra nito.. malakas kutob ko thermostat..

pero thermostat nito e kasama na hose housing... di sy ung thermostat lang, so nasa luob sya ng plastic elbow .. so pano na to.. maalis ba to?

sa casa worth 1550 pesos ang isa nito, sa labas naman e 700 pesos ito.. both orig. naman. hirap kasi makahanap replacement nito sa labas...

kung bumili ako at palitan to, would it solve the problem?

kasi nagprepresure na naman sa kotse... e so sinira na naman nya ung rad cap ko.. grr.. P329 pesos pa naman bili ko nito kahapon lang.. ok pa naman pero parang pinuwersa ng steam na naman...

how would you know kung sira ang thermostat? me way ba macheck? other than baklasin ko at palitan agad? gusto ko na maayos ito kasi kung mag overheat palagi yari ang engine ko nito

ung radiator ko e nagawa na, so copper na ung taas nito, ang orig at replacement nito e plastic lang... kakapagawa ko lang nito nung aug25....

me fuse ba sa radiator? o purely mechanical un... na palitin...

me warranty ba un? ung thermostat.. o parang supplies lang un na me wear and tear?

**jick.cejoco** · October 11th, 2010 07:08 AM

Originally Posted by joseph_abri

bakit kaya ganun pag nilagay ko sa full ung aircon tapos naka heater mode... me hot at cold kasi ung aircon ko, biglang bumababa ung temperature, as in super bilis, bumabalik sa normal..

sabi ng kuya ko, sabi daw ng mekaniko ng nissan (para sa serena nya) at toyota (para sa vios nya) e pwede daw tanggalin ung thermostat.. wala ng thermostat un daw kadalasan rason ng overheat kasi nag stuck up at di nagbubukas ung themostat.... kaya alisin na daw kasi di naman tyo cold weather at tropical tyo so di na kailangan un, kailangan lang daw un sa mga nagfrefreeze ung oil, and water sa lamig... para mabilis uminit, sa pinas di na daw.. totoo ba to.. alisin ko?

eto pa.. kakapalit lang sa kasa ng thermostat... sa chevrolet. aug 25 alam ko meron ata nitong 3 month warranty... kasama kaya to .. palitan kaya nila.. baka sabihin lang nila iba cause ng sira palitan ito, ito, at ito baka mapamahal pa ko sobra..

at ano ba ung nabasa ko dito na thermostat switch? san un, meron ba ang optra nito.. malakas kutob ko thermostat..

pero thermostat nito e kasama na hose housing... di sy ung thermostat lang, so nasa luob sya ng plastic elbow .. so pano na to.. maalis ba to?

sa casa worth 1550 pesos ang isa nito, sa labas naman e 700 pesos ito.. both orig. naman. hirap kasi makahanap replacement nito sa labas...

kung bumili ako at palitan to, would it solve the problem?

kasi nagprepresure na naman sa kotse... e so sinira na naman nya ung rad cap ko.. grr.. P329 pesos pa naman bili ko nito kahapon lang.. ok pa naman pero parang pinuwersa ng steam na naman...

how would you know kung sira ang thermostat? me way ba macheck? other than baklasin ko at palitan agad? gusto ko na maayos ito kasi kung mag overheat palagi yari ang engine ko nito

ung radiator ko e nagawa na, so copper na ung taas nito, ang orig at replacement nito e plastic lang... kakapagawa ko lang nito nung aug25....

me fuse ba sa radiator? o purely mechanical un... na palitin...

me warranty ba un? ung thermostat.. o parang supplies lang un na me wear and tear?

if i'm not mistaken, there is a bleeder plug close to the thermostat housing. most newer cars have the radiator lower than the engine that's why the manufacturer includes a bleeder screw at the highest point of the cooling system, usually the thermostat housing. as per the thermostat check, this can be done by boiling water and immersing the thermostat in it while observing with a thermometer as to how hot the water is when the thermostat begins to open. most manufacturers recommend using oil for this but is safer and more convenient to use water since you would not want motor oil in your cooking pots and is a fire hazard when you use an open flame stove

**ARB** · October 11th, 2010 07:53 AM

normal lang yan if you put sa heater ang aircon lalamig ang temperature since the cold air frm the aircon passes thru the heated hose galing sa rad mo. maybe there is air in the system. anong coolant/water mix gamit mo

**rmpmla** · October 11th, 2010 08:41 PM

Originally Posted by joseph_abri

if i put the aircon heater at the hottest temp, the temperature goes back to its normal below half level... but without it, lets say i put a cool airconditioner, it goes high, or when there is none, as well but a bit slower

ibig sabihin nyan sir ay nag function as a radiator yung aircon heater mo kaya bumaba ang temperature reading mo. may linya kasi ng coolant galing ng engine ang pumupunta sa aircon heater.

Check mo sir baka naman mahina yung buga ng radiator fan mo at hindi nya kaya palamigin yung coolant sa radiator. May instance kasi na umiikot yung radiator fan pero di malakas ang buga.

**phezthie** · October 11th, 2010 09:34 PM

Originally Posted by jick.cejoco

have a pressure check on your cooling system. seems like you guessed all the way through and yet the problem persists. with a system pressure check, any and all minor leaks appear. if your system can not hold and maintain pressure, it will overheat

yup, have a pressure check first.. that way you can determine if its a cooling system problem. otherwise, perform a leakdown test to know if engine trouble is the culprit, ie. cyl head leak, gasket, or valve problem...

**benchman** · October 13th, 2010 10:28 PM

hmmm... napalitan na yung thermostat, aux fan(for the condenser?), rad cap....nag-iinit pa din?
how about the rad fan blowing/facing the engine, working po ba? is it still pushing good amount of air?

posibleng sa cylinder head(gasket, valves etc...) kung ruled out na yung mga nasa itaas.

about the thermostat, strange that those alleged Toyota/Nissan CASA mechanics suggested to take out/disable your thermostat? sila lang yata ang CASA na narinigan ko na nagrekomenda nang ganon.. old school mekaniko pwede pa siguro, yung hindi alam or hindi naiintindihan ang talagang trabaho ng thermostat ng engines.

you did it right sir na pinalitan mo yung thermostat, but how come? positive for failure na po ba sya? genuine po ba yung ipinalit nyo?
regarding thermostats, advisable po talaga na genuine na ang ipapalit nyo kung sira na talaga para sigurado.
may certain temps and pressure limits(PSI) po kasi yung mga thermostats for each car make/model para gumana sya ng normal.

kung nasa inyo pa po yung old thermostat, pwede nyo po syang i-test kung working pa sya by;
put the thermostat in any kaldero na may tubig then put it on stove, let the water boils and observe the spring/valve if it will open/moves, pag no movements at all... sira na nga sya.

my advise lang po... wag nyong tanggalin yung engine thermostat ng kotse nyo

malaki po talaga ang trabaho nyan sa makina naten...
those engineers will not burn their asses sitting/thinking to design and install those thermostats at our engines without any cause?

though i'm not an expert nor a mechanic here to convict pero based na rin po sa experience at sa inputs na nakuha ko sa competent na mekaniko ko at sa CASA mechanics.

just my 2 cents lang po...