Quote Originally Posted by wickednasty View Post
Good morning fellow tsikoteers.. hingi lang ako ng tips on how to resolve my car's cooling system problems. several months ago, my car experiences an increase in temp after 2 hours of driving.. regular yun from QC to laguna, paghinto ko bago pumasok ng gate, tumataas na temp up to 3/4. after checking under the hood, i noticed na puno ng coolant yung reservoir bottle tapos may bubbles pa na nagooverflow. then right after the engine cooled down a bit, i checked the radiator and halos wala nang tubig. after several diagnosis from different mechanics, first thing i did was to replace the reservoir bottle kasi medyo loose na yung thread nung cap. 2nd was to change the thermoswitch kasi sabi ng mechanic matagal raw bago umikot yung fan, then kung iikot man, about 5-10 seconds lang. still, those two remedies didnt solve the overheating problem. 3rd thing i did was to have my radiator overhauled and had the radiator cap replaced as well. after this, nawala na yung problem. this was done last january lang. im sure the overhaul somehow contributed something to "lessen" the problem kasi di na nagbabawas ng tubig yung radiator unlike before. di na rin nagooverheat when driving from QC to laguna.

But then last night, i drove from Roxas Blvd to Laguna, then when i stopped to get gas, while i was in queue, i noticed na tumaas nanaman yung temperature. so i turned the engine off and checked my car's cooling system, and ayun, ganun nanaman yung problem. nagooverflow yung water sa reservoir bottle. i didnt check, but im sure wala na masyadong water sa radiator. the only difference from last night compared to the onter nights where i drove for at least 2 hours was the heavy traffic. madalas kasi late at night ako bumabyahe from QC to laguna, pero last night nakipagsabayan ako sa rush hour.

another thing i noticed, bumababa yung temp to normal when the car is moving, then rises nga when idle. my thoughts about this is yung air na tumatama sa radiator serves as a cooling factor to it.

ano kaya REAL culprit sa problem na to? thermostat, cylinder head gasket and waterpump nlang natitirang pwedeng maging problema. i checked this morning, and wala nman ako nakikitang water leak na pwedeng manggaling sa waterpump.

possible kaya na sira yung thermostat kaya nagmamalfunction na rin yung bagong palit na thermoswitch? which results to the radiator fan not working properly. i also checked this morning lang, working and umiikot naman yung fan. im just not sure if its being turned on when its supposed to be spinning.

looking forward to your responses.. sana hindi cylinder head gasket yung prob.. hehehe.. medyo mahal parts and labor nun eh.. but if the symptoms above matches sa problem ng failing cyl head gasket, do tell.. pa include na rin ng estimated cost for parts and labor.. civic ESi yung car.. thanks in advance...

wicked,
to put an insight into your modern car's cooling system, they are normally designed to operate at optimum efficiency by conserving heat and at the same time prevent your engine from overheating. your car is designed to operate between 190-240 degrees fahrenheit to reduce exhaust emissions of unburnt fuel and prevent the formation of oxides of nitrogen in case of an overheat. your car's radiator contains less coolant compared to the cars of the sixties where the capacity is less demonstrated by a small single row radiator for three reasons: 1.- warmup time is reduced, 2. -the vehicle is lighter with less coolannt, 3.- the engine is not overcooled.
the system is cooled two ways; a. by the fan thermoswitch controlled fan, b. the ambient ram air when the vehicle is in motion. your description of the symptoms is that it happens when there is no ram air. things that can contribute to this vehicle stopped/engine running overheat are:
the radiator airlow is blocked by a bugscreen or nosebra, the radiator has been painted over insulating the cooling fins, the radiator fan is unable to pull or push air through the radiator or leaves or debris are present in front of the radiator.
in the case of the coolant not returning normally rom the recovery(reservoir, surge tank however you may call it), check for partially clogged hose between the radiator filler neck and the recovery bottle and for vacuum leak on the hose. you've mentioned that the radiator cap had been replaced. the normal rating for honda caps is 0.9 kg/sq.cm.(roughly 13 p.s.i.) check for pressure valve gasket or seal and the vacuum valve seal on the same cap(compound cap). for lack of complete information of your car, check to see if the cooling system needs to be bled as today's cars have lower hoodlines and the radiators are usually lower than the engine trapping air pockets in the cylinder heads.
jick