cooling problems

[blur]

good day mga gurus..

im driving a 99 SiR now my prob is whenever i get home i hear something like boiling under my dash, upon inspecting it yun water sa radiator pala mainit siya but hindi naman ata over heat natatapon lang sa expansion tank pero umuusok siya sa init, one more thing na na notice ko is my temp gauge doesn't go beyond 1/4. need your help kung anu dapat gawin (got the car 7 months ago)

thanks a lot

[speedyfix]

check/change the radiator cap muna.

[Brent]

There might also be a hairline crack on your radiator. Especially if its still the original one and you've never replaced it. Happened to me before.

[Accord GTR]

good day mga gurus..

im driving a 99 SiR now my prob is whenever i get home i hear something like boiling under my dash, upon inspecting it yun water sa radiator pala mainit siya but hindi naman ata over heat natatapon lang sa expansion tank pero umuusok siya sa init, one more thing na na notice ko is my temp gauge doesn't go beyond 1/4. need your help kung anu dapat gawin (got the car 7 months ago)

thanks a lot

I don't understand what you are complaining about since it is not overheating.  It sounds normal to me.  Coolant temp is really hot.  Because it is under pressure, it reaches higher than regular boiling point of water or up to 190F or more.  When you stop the engine running, the coolant temp spikes so the function of the radiator cap is it has a to relieve the excess pressure so coolant overflows to the plastic reservoir tank.  That's what you are probably hearing. Then, when the coolant cools down, the negative pressure inside the radiator sucks back the water from the reservoir to maintain the water level inside the cooling system.  Basic chemistry: increase temp = increase pressure & vice versa.  This is normal for all cars.

Just don't openthe radiator cap when it is hot like I see those gas station attendants do.  Maintain the water level between the min-and-max marks in the reservoir tank.  Drain your radiator every 6 months and replace with distilled water and coolant as well as clean the external fins.  A leaky or dirty radiator will eventually cause overheating.   

[blur]

thanks for the replies sir speedyfix sir brent and sir accordGTR,


"I don't understand what you are complaining about since it is not overheating. "
hmm kase sir nauubos yun water ko sa radiator,

i tried replacing the rad cap na rin, still the same..

what i did was took out the thermostat afterwhich okay na hindi na ngboboil yun water.. im still thinking of putting in a new thermostat... anyways thanks a lot

[speedyfix]

when in doubt replace it. mura lang thermostat and it can't hurt naman kung bago.

[Emong3]

check the type of radiator installed, dalawang klasi ang radiator ng honda, isang type-D and isang type-F. Metal top and plastic top.
radiator cap ng plastic top will fit a metal top but it will not do its job.

make syre you are using the correct radiator cap and it is 1.1 bar rating.

madami ako nakikita nagpapalit ng evercool or any metal radiator pero hindi nagpapalet ng radiator cap. overheat or kung hindi man overheat nag babawas ng tubig radiator.

[blur]

sir speedyfix sir emong thanks for the replies.....



was able to get a 1.3 bar rating na rad cap.... i seems to work out well..

i checked my radiator and plastic nga top nya...

ill be installing a thermostat soon.. you think yun low temp na thermostat is worht it??? or should i get just the regular thermostat??

hmm im using my car sa track din paminsan minsan

[Emong3]

better kung maka bili ka ng aftermarket thermostat na mas mababa ang temp rating. stock i think is 78 degC. May mga aftermarket like spoon 65 degC.

[blur]

thanks a lot sir emong.. and sa lahat ng ng reply..thanks

[speedyfix]

the lower temp thermostat can't hurt. sulit naman yung mga yun.

[blur]

got it sir speedfix again thanks a lot....

ill drop by your shop next time ill have my change oil ill try yun RP promo mo sir...

[Accord GTR]

Ok since we are talking about aftermarket radiator caps and thermostats, lets take this discussion further...

1.  Thermostat.  The function of one is to bypass or block the cooling system to your engine when your engine is below the thermostat temp opening point.  When your engine is cold, the oil has a hard time circulating or is still thick and will give less protection to your bearings and piston rings as well as give you less compression.  Also the engine runs leaner and if you try to put load or give it high throttle, you can damage your engine. 

The reason why the Honda thermostat opens at 78C is because the best operating temp for a Honda engine is around 80-90C.  When I dyno'd my engine, it makes more power when its actually closer to 90C than 80C.   So I don't know why you have to put a Spoon thermostat that costs so expensive and opens at a lower temp.  Opening at a lower temp does nothing for your engine nor will it make it run cooler.  If you have a problem with cooling, chances are it is not the thermostats fault anyway.  You can remove the thermostat but this will make the engine warm-up longer, which can wear out your bearings, piston rings, valve guide seals, etc.  sooner than later.

Another function of the thermostat is to keep your engine at "operating temperature" during cruising or low load conditions or cold weather.  When you are on the highway for a long time, the engine coolant can go below 78C so the thermostat closes to allow the engine to heat up again and thus operate at its most efficient level.

Re: Spoon thermostat...68C (coolant temp) is too cold for a Honda engine IMO.  Maybe you guys should try it on the dyno next time...dyno a cold engine at that COOLANT TEMP (68-80) then dyno when its warmed up to 80-90C and you will see what I mean.  Heat is good for an engine so long as it is within a certain range.  So long as your stock engine temp gauge is normal, don't worry about it.  of course, if you have a leak somewhare then that's another problem.  For racing, you can remove the thermostat if you want but this isn't really necessary.

2.  Radiator Cap.  The function of the radiator cap is to keep the cooling system under pressure and release that pressure to the overflow or reservoir tank if the pressure goes above a certain point.  The stock cap is 1.1 bar.  Again, I dunno why people have to replace that with a 1.3 bar cap.  That only puts added pressure on your cooling system which would increase chances of springing a leak somewhere.

Emong was right...critical to use the correct cap in reducing coolant leak.  For this reason, I would not recommend going to a local radiator becaus they may not have the right cap available.  Also I do not recommend the stock Civic half-width radiator as it is too small.  I recommend using a full-length Honda radiator like surplus Integra or City.  Critical is mounting...if there is a large gap around the radiator, air will escape through that gap and not THROUGH the radiator fins.  This will reduce cooling efficiency drastically. 

If Honda thought a colder thermostat or stronger radiator cap was good for your engine, they would have put it on there.  i just use stock in my race car that races at VTEC till 9000rpm for about 24 minutes in 50C heat or more without overheating.  With a surplus Integra radiator my engine runs a cool 90C or lower even in the hottest of days at Subic.

Water boils at 100C at normal atmospheric pressure.  With a 1.1 bar radiator cap, plus alcohol coolant added, the boiling point is raised to around 110C.  When the coolant turns into a gas, it does not circulate and cool your engine anymore so this is the "overheating point".  The main causes of overheating are only 4 main categories:

1.  no engine oil lubrication or breakdown of oil viscosity.
2.  no airflow thru radiator or clogged radiator
3.  no coolant circulation or low coolant
4.  lean air/fuel mixture or detonation

All the other reasons will fall into the above categories or it can be a combination of 2 or more problems.

[aid03]

if its a daily then, imo, i don't think it matters whatever you put in there. accordgtr is right though, why spend more if a regular part will do the same thing. and, pushing a warm engine is better than pushing a cold one.

[stoked92]

good day mga gurus..

im driving a 99 SiR now my prob is whenever i get home i hear something like boiling under my dash, upon inspecting it yun water sa radiator pala mainit siya but hindi naman ata over heat natatapon lang sa expansion tank pero umuusok siya sa init, one more thing na na notice ko is my temp gauge doesn't go beyond 1/4. need your help kung anu dapat gawin (got the car 7 months ago)

thanks a lot

usok means steam and steam comes from evaporated water (boiled/overly heated)... there might be something wrong in there.
anyways, had the same problem before. i had no leaks, water pump was ok.. and then i noticed, my rad fan wasn't working. it's just that i'm lucky that i didn't experience any traffic jams that's why the air coming outside was the one cooling my rad while i was cruising at 40-80kph. further inspection revealed that my rad fan relay got busted, so i just bought a new one and replaced it.

check if your rad fan / main fan is working, if not, then it might be something else.

hth.