Should you remover thermostat?

[kompressor]

wrong past experiences can not be a basis of judgment. the automobile has leaped in technology about fifteen times from ten years ago. if somebody boasts of doing for 30 years of wrong procedure or theory, they had been wrong all that time. training and education is the key. that is why, today's auto workers are called technicians and not mechanics. there is more to the car than mechanical items

My point, exactly! No wonder super allergic sila sa mga bagong engines which are ECU controlled and have variable valve timing or common rail direct injection pag diesels.


OT:
I remember may binara akong mayabang na jeepney driver at a police station (during a traffic incident investigation). Kesyo 20 years na daw siyang nagmamaneho and baguhan lang daw yung nasabitan niya/sumabit sa kanya so I got irritated with his condescension. Hiniritan ko ng: "Nag aral ka ba? Kahit 20 years ka nang driver, kung mali mali ang pagmamaneho mo eh walang pinagkaiba yan. Maniniwala pa ako sa baguhan pero nag aral magmaneho".

[KIANTOT]

Actually, the previous comments stated na pag walang thermostat ay overcooled ang engine. Napasok lang sa discussion ang overheat kasi nga common practice ng mga "traditional" mechanics na tanggalin ang thermostat as a band-aid remedy against overheating. And ang line of reasoning nila ay "dinesign yan para sa Japan eh wala naman tayong taglamig".

Regarding your previous testimony, you should have replaced the thermostat with an OEM one instead of removing it. If there are no leaks or clogged lines in the cooling system and the thermostat and water pumps work properly, the same situation you mentioned (parked with engine and a/c on under sunlight) can be achieved even with the thermostat installed. Done them both on a Tamaraw FX (7k) and a Nissan Vanette (LD20 diesel) without overheating. Both with thermostats intact.

You also mentioned that you did notice your engine's response to be sluggish when the temp needle is below the ¼ range. That is because your oil's viscosity is not maximized if your engine's temp is not in the optimal operating temp range. This will result to premature wear and tear. You'll be experiencing loose cylinder compression earlier than those who do not remove their thermostat. Not to mention, a noticeable drop in fuel economy. Of course, thermostats are bound to fail due to wear and tear but if you're conscious about your vehicle's maintenance, you'll be aware that a thermostat is due for replacement without having to experience an overheat. Just be conscious of your temp gauge like a driving teenager-wannabe-racer who always looks at his speedometer.

Agree about what you have said about the benefits of having thermostat installed, so far my AUV is still in very good condition, I remember that I removed the T-stat before I change my timing belt about 90t kms.....last month already change again my t-belt for the 3rd time, until now, I haven't installed the new t-sat

[weisshorn]

My Own Opinion: Leave that thermostat in the engine. Kung may overheating problem ang makina dapat hanapin ang root cause at ayusin. Kung ang suspect ay thermostat, syempre i-check & test kung ang function nya ay normal ayon sa dapat, kung hindi naman eh dapat palitan.

[jick.cejoco]

in my over 20 years experience as an automotive service technology instructor aside from my experience in the shop working on any equipment that runs on the highway and automobiles, some people refuse to learn and some people never learn. let's face it, the modern automobiles require a more restrictive breed of technicians who respect training, correct information and a little advise from the experienced professionals. if in doubt, get some training and get some education. never stop learning. everyday is a new day and everyday some car manufacturer comes up with something new

[yapoy86]

we have a kia besta dati 2.7 diesel engine.. walang thermostat pero ang temp na maintain nya is 1 notch before mag half ng gauge.. hindi nag ooverheat yan.. pero kahit walang thermostat sa umaga kahit malamig ang panahon or umuulan wala pang 15 mins eh halos nasa half na ang temp nya.. tapos maintain na yung temp na yun kahit tanghaling tapat..

isa pang problem eh car manufacturers design their cars for global use eh majority ng car market eh nasa mga malalamig na bansa.. unlike saten na tropical country.. meron bang engine specifically designed for the philippines?? wala naman diba.. lahat ng engine designs came from cold countries like japan, germany, usa, korea etc....

[jick.cejoco]

once again, some people refuse to learn and some people never learn. they insist on the little wrong knowledge they might have. the boiling point of water is 212*F (100*C) at sea level up to about 1000 feet above sea level assuming you are at atmospheric pressure regardless you are in Switzerland or you are in Nairobi. the combustion temperature remains the same regardless of your geographic location. you control the combustion temperature that way you control combustion efficiency and control air pollution. not the other way around. again, study!!!!!

[kompressor]

In fairness to the others, let's try to exercise constructive criticism instead of using a condescending tone. Condescension will only invite arguments instead of healthy discussions.


BTT:

*KIANTOT, I believe you didn't experience overheats during your first 90k kms, right? It's living proof that a properly functioning cooling system does not require the removal of the thermostat. It's still better to find the root cause once an engine overheats.


My assumption is that you may be using a good multigrade oil that adjusts to your engine's temperature that's why I also assume that your engine's compression is still in very good condition even after the mileage it incurred. However, did you notice a slight difference in your fuel economy after the thermostat is removed? Just like what was said earlier, a diesel engine is very dependent on the combustion chamber's compression and TEMPERATURE. Diesel injected at the same compression ratio but with a lower temperature will have a different burn compared to diesel injected at an engine's optimal operating temp vis a vis with its matching compression ratio. Just like with my experience, I consumed more diesel before I found out that the mechanic removed the thermostat. The difference is not that much during highway (however, still noticeable) driving but really mattered on city driving. Pag mas mababa kasi ang temperature, the more you need to step on the throttle to attain more power but at the cost of smoke and fuel economy.

[yapoy86]

well the point is the thermostat is there to 1. reach operating temp as fast as possible and 2 maintain that temp during the operation.. but again some engines cooling system like the one we have in the kia besta can do that without the thermostat..

[miked]

isa pang problem eh car manufacturers design their cars for global use eh majority ng car market eh nasa mga malalamig na bansa.. unlike saten na tropical country.. meron bang engine specifically designed for the philippines?? wala naman diba.. lahat ng engine designs came from cold countries like japan, germany, usa, korea etc....

afaik, automotive engineers design these vehicles with regards to the ambient conditions of the targeted market place even if they are designed and assembled at colder countries.

[miked]

well the point is the thermostat is there to 1. reach operating temp as fast as possible and 2 maintain that temp during the operation.. but again some engines cooling system like the one we have in the kia besta can do that without the thermostat..

yes. maybe. but at a cost. like slow murder of the engine.

[KIANTOT]

In fairness to the others, let's try to exercise constructive criticism instead of using a condescending tone. Condescension will only invite arguments instead of healthy discussions.


BTT:

*KIANTOT, I believe you didn't experience overheats during your first 90k kms, right? It's living proof that a properly functioning cooling system does not require the removal of the thermostat. It's still better to find the root cause once an engine overheats.


My assumption is that you may be using a good multigrade oil that adjusts to your engine's temperature that's why I also assume that your engine's compression is still in very good condition even after the mileage it incurred. However, did you notice a slight difference in your fuel economy after the thermostat is removed? Just like what was said earlier, a diesel engine is very dependent on the combustion chamber's compression and TEMPERATURE. Diesel injected at the same compression ratio but with a lower temperature will have a different burn compared to diesel injected at an engine's optimal operating temp vis a vis with its matching compression ratio. Just like with my experience, I consumed more diesel before I found out that the mechanic removed the thermostat. The difference is not that much during highway (however, still noticeable) driving but really mattered on city driving. Pag mas mababa kasi ang temperature, the more you need to step on the throttle to attain more power but at the cost of smoke and fuel economy.

Sure bro no problem for me at all, Im always glad to read everyone's idea's just only share what I have experience, just want to clarify also, I'm not saying "it's better not to put the t-stat"

BTT:

I did'nt experience overheating at all since I left my AUV, the cooling system is always good that time I have been using it, it is properly maintain that's why never experience din na "Tumirik" or nasiraan sa daan. Ang naging cause na lang kaya nangyari na nag overheat for 3 times kase negligence ng driver (brother ko) to check the water and never look on the temp gauge, pinatuyuan ilang beses, Yes it is not the solution to overheating problems by removing the thermostat, sure na may problema yung cooling system.

but I think not the oil that I have been using pero usually I'm using it always with in the city beacause it is " for hire" all day imagine kahit tanghali tapat, that's why heavy duty use, na encounter ko lang naging sluggish siya down the hill kapag ang route ko antipolo at umuulan sa gabi, true kapag nga mababa ang temp the more you need to step on the throttle kapag walang t-stat, pag dun lang ako napunta, pero the rest ok naman kahit sa FC walang pagbabago dahil sa city lang madalas ang route ko.

[tip_tipid]

once again, some people refuse to learn and some people never learn. they insist on the little wrong knowledge they might have. the boiling point of water is 212*F (100*C) at sea level up to about 1000 feet above sea level assuming you are at atmospheric pressure regardless you are in Switzerland or you are in Nairobi. the combustion temperature remains the same regardless of your geographic location. you control the combustion temperature that way you control combustion efficiency and control air pollution. not the other way around. again, study!!!!!

agree, even desert sold cars are equipped with standard T-stat.

[MrQ5]

once again, some people refuse to learn and some people never learn. they insist on the little wrong knowledge they might have. the boiling point of water is 212*F (100*C) at sea level up to about 1000 feet above sea level assuming you are at atmospheric pressure regardless you are in Switzerland or you are in Nairobi. the combustion temperature remains the same regardless of your geographic location. you control the combustion temperature that way you control combustion efficiency and control air pollution. not the other way around. again, study!!!!!

ang alam ko po pag mataas na altitude bababa ang atmospheric pressure, need to review my chemistry nakalimutan ko na din eh

[s10pao]

ang alam ko po pag mataas na altitude bababa ang atmospheric pressure, need to review my chemistry nakalimutan ko na din eh

tama sir kasi mas manipis (in terms of volume) ang hangin habang pagtaas ng altitude

[miked]

ang alam ko po pag mataas na altitude bababa ang atmospheric pressure, need to review my chemistry nakalimutan ko na din eh

right on. the boiling point also decreases as well.....

[Smoked2020]

Very interesting topic indeed. i might also share my insight on this one, i own a honda city type z, as we all know city are well known for low fuel consumption, (of course it depends on the driving habit, traffic condition etc,) a year ago i had a problem with my radiator and my mechanic also remove the T-stat because as he said it is already faulty and told me that it is not really that important and so on. since then i have experienced a very significant increase in fuel consumption. fuel consumption was in about 12-13 km/l before but now it's barely 8-9 km/l. maybe this could be the cause of it. I don't know much about cars so it is a good thing that we have this forum. I've learned a lot from this topic and should bring my car to the shop and have my T-stat replaced soon. hope it would resolve my fuel consumption issue... dahil nag babadya na naman mag taas ng 2 pesos ang Gasolina. Ouch

[kompressor]

Very interesting topic indeed. i might also share my insight on this one, i own a honda city type z, as we all know city are well known for low fuel consumption, (of course it depends on the driving habit, traffic condition etc,) a year ago i had a problem with my radiator and my mechanic also remove the T-stat because as he said it is already faulty and told me that it is not really that important and so on. since then i have experienced a very significant increase in fuel consumption. fuel consumption was in about 12-13 km/l before but now it's barely 8-9 km/l. maybe this could be the cause of it. I don't know much about cars so it is a good thing that we have this forum. I've learned a lot from this topic and should bring my car to the shop and have my T-stat replaced soon. hope it would resolve my fuel consumption issue... dahil nag babadya na naman mag taas ng 2 pesos ang Gasolina. Ouch

Did you observe where your temp needle stays after the thermostat was removed? If it stays in the 1/4 and below level, then you'll be running rich since the ECU will operate in "enriched" mode.

You might also want to do a spark plug reading. My guess is, dark colored ang plug tips mo and not golden brown after the t-stat was removed.

[Smoked2020]

Did you observe where your temp needle stays after the thermostat was removed? If it stays in the 1/4 and below level, then you'll be running rich since the ECU will operate in "enriched" mode.

You might also want to do a spark plug reading. My guess is, dark colored ang plug tips mo and not golden brown after the t-stat was removed.

yes, the temp needle never went up over 1/4 level or if it does, it wont go up to the middle. the spark plugs was replaced about 5 months ago when i had a tune up, so i am not sure how it looks like today.

the thing is i did replaced my thermostat, it has been 2 weeks now and i have not seen any improvement on my gas mileage. i have had a half tank of gas, i've reset the meter and now i have 125km reading and the needle pointer is almost at the bottom. i have not been stocked to traffic so i guess it's not counted anymore.

what can you suggest guys, mkikita ba agad ang problem kapag pina diagnose? any idea kung how much ang padiagnose? TIA

[isa1023]

Did you observe where your temp needle stays after the thermostat was removed? If it stays in the 1/4 and below level, then you'll be running rich since the ECU will operate in "enriched" mode.

You might also want to do a spark plug reading. My guess is, dark colored ang plug tips mo and not golden brown after the t-stat was removed.

Upon removing the thermostat, we assume that the engine will never reach ideal operating temperature in ideal time on normal driving conditions.

On EFI systems, the ECU will run rich mixture on "closed loop" after cold starts.

Does that mean it will always run "closed loop", ie not all sensor signals considered, when you remove the thermostat?

[jick.cejoco]

Upon removing the thermostat, we assume that the engine will never reach ideal operating temperature in ideal time on normal driving conditions.

On EFI systems, the ECU will run rich mixture on "closed loop" after cold starts.

Does that mean it will always run "closed loop", ie not all sensor signals considered, when you remove the thermostat?

correction:
the engine runs on open loop when you first start it and remains in open loop until the coolant temperature signal reaches about 170 degrees fahrenheit. if the CTS is bad (high resistance), the controls remain in open loop regardless you have been driving all day. it also remains in open loop if the engine is overcooled. when you press the throttle above 40% it goes to open loop from closed loop. the closed loop happens when the parameters such as warm engine, throttle not above 40% and there are no problems that would affect the controls to go on limp mode