thermostat for mr2 - need it?

[mrtwo]

hola peeps

i went to flush my coolant the other day and i saw this TRD thermostat. Tempted, i ask the mechanic to install it. when he open the place where the thermostat is, THERE IS NO THERMOSTAT! my mr2 does not overheat but its just that there is "foam" coming out from the spare water tank when u drive an average of 80 to 100km/h then idle.. oil temp is around 90 to 100 0c and water temp is 1/4 to 1.5/4 of the original meter.

could it be bcause there is no thermostat? is it because there is no thermostat to hold the pressure hence the coolant move freely to the spare tank? hehe dunno la...

some ppl say different things to me, eg, got thermostat better, no thermostat better , racing thrmostat better...aiyoh..i also donno who to follow. the mr2 is still running without thermostat cuz that TRD thermostat is meant for other car :(

thanks to all sifus here if u can tell me some ideas~!

cheers

 

[EDDYSW20]

The thermostat is an important component to control when the coolant starts to flow around the engine block. Its supposed to run around the block/system once temperature is high say around 65 celcius.

Only confusing statement you mention is thermostat hold pressure? coolant move freely to spare tank? You may have confused the thermostats' function with that of the radiator cap which is supposed to release coolant to the tank in case of an excess pressure. I will not install that unless I've fortified the rubber hoses and know the engine seals are new or strong, cause the pressure inside the coolant system can be pretty high and rather have that fluid release its pressure externally than internally.

Anyway, please clarify which part you do not have installed. Thermostat tarak means your coolant is super cool, no restriction from engine start, and engine block temperature rises ever so slow...... not good for sprinting a minute after starting your engine....

 

[mrtwo]

hi there eddy thatnks for ur explanation -)

i did some spirited driving last nite and what i see is the original water temp needle is 1/4..my oil temp is 100 oc .when i idle the car the watr temp is above the middle , 3/4.. and that foam came out again..it seems that the car has bubble in it... i cant think of any problem except for this thermostat thing..

yup u r right.it takes me like 5 min after starting the engine to warm up the car..normal driving is great..my problem is that when u press the engine harder, is it possible that the coolant cant be cooled enough (pass thru aluminuim radiator - forged racing) since there i no thermostat? is it possible the coolant pass thru the radiator fins too quickly, hence there is not enough time to cool? so the heat slowly builds up and eventually overheating? ( 3/4 of the meter reading)..

i planning to put racing thermostat but will it solve my problem?
and yes that reddish foam came out from the spare tank yucks..(toyota coolant)

thanks for comments ..sorry if i give lame opinions newbie for a petrol engine and mid engine car :)

---------- Post added at 01:18 PM ---------- 6 hour anti-bump limit - Previous post was at 01:17 PM ----------

after spirited driving ,cuise for 5 minutes then idle

 

[midship]

Thermostats would not have been invented if they were not needed...

 

[EDDYSW20]

Midship, thats the perfect way to think!

Mrtwo, so, temperature rises and coolant foams when you're driving with the spirits eh?!

First, pretty sure the missing thermostat was the reason, will tell you how shortly.

Second, the high temp and foam could be due to 2 reasons, 1st the coolant is full of rust and pipe water, or 2nd, you've got a leaky head gasket. The later may prevail to be true.....

Third, either reason, you'll need to flush the coolant system, fill up 2 bottles of coolant and the remainder water. Then make sure you level off the car and get the trapped air out, termed bleeding the system. Follow the manual to detail la.

So, now, why I say the later is true..... in simple terms, without a thermostat, coolant temp is low, combustion chamber is high, the difference can warp the block or at least 'shift' it. First to go is always the head gasket, then you'll note exhaust smells 'sweet', coolant loss, engine oil loss, turbo pressure loss, early morning start issues, engine idling issues, and finally engine ceases to operate. It depends which part of the gasket has leaked. Yours could be water to combustion chamber, during normal idle, the water pressure is low due low temp, but as the boost increases, combustion pressure leaks into the coolant system, causing the coolant to cook, or overheat to an extend, but due to your super-efficient-no-thermostat system, the temp is kept pretty regular hovering at 3/4, continue the rev and boost for a straight 1 minute and that would boil the water, blow the cap, and experience coolant lost. But to be sure, turn off the engine immediately, and you'll get water into the combustion chamber, by virtue of difficulty to start a minute after shutdown..... don't do that unless you have a standby halfcut!

Good news though, this is easy to check, do a combustion chamber pressure check, all should read the same pressure. Check the oil for sign of water or bubbles, and check the water for sign of oil or reflection off the coolant surface. Just for assurance...... get back to us once you've done these..... we can diagnose it further......

 

[xtremeleo]

if its a question of needs, yes sir, ur engine needs the thermostat to operate at its optimum capacity

 

[mrtwo]

aiite.. dat coolant no oil, that engine oil no water, no sweet smell, no idling issues..i drove last nite and one thing i realize, when i turn off the engine (turbo timer equipped) the two fans running at maximum speed..and i keep an eye of the water temp and it slowly drops including the oil temp..i put 6 minutes and the foam no more and the engine is just fine..but when i turn on the engine, i realize the fan run slower..i decided to check them today and i found out that the fuse isnt working for the right-hand fan.wireman says that da right fan will always on, while the left fan detects heat temperature from the engine.. i dont know how far true this conclusion is but he changed dat fuse..(boxy - look)and the right fan works perfect! now i can hear the fans loudly.. i will test it again ..and hopefully its only that boxy fuse is the cause of that foams.! (heat dissipation)..meanwhile i will source thermostat~ midship, extremeleo and eddy, u are right ;this thermostat will not be invented if it is useless~

 

[EDDYSW20]

Huahahahaha...... Are you talking bout bubbling at the overflow tank? Hayaaa, I kena con oredi laa.... hahahaha.... Well, the fan not running and the fact that your engine was shutdown with insufficient cooling-down period fits the description of a gurgling or bubbling sound from the bottle/cap area..... Good news, yes, fixing the fan and increasing you cooling down period to >3 minutes before shutdown will solve this concern. Make sure your bottle if filled with coolant and you're ready to sprint!! Hahahahaha..... cheers....

 

[alvin24]

whoa... more than 3 minutes for turbo timer... not too long ka?
Surely get disgruntled neighbours... lolz

 

[EDDYSW20]

Only if trashing the car.... petrol wasted a little, but neighbours no problem..... standard pipes all the way.... its pretty quite..... I think..... hahahaha...

The best practice is to drive relaxed 2 minutes before approaching your home, slowdown around housing area maaaa....... donch want your blow off to wake the neighbours kid! Sure disgruntled laaa..... hehehehe

 

[mrtwo]

hi peeps...yup that fuse is the main problem ~!

thanks for the advise..i drove up to SS2 - klia- putrajaya-home without problems ~

i attached the fuse pixs to share with...note that there is a dark (burnt) surface on top of the brown fuse ...

dun care what the neighbours will say, my baby needs to rest!

thanks

 

[mrtwo]

so, how much is trd thermostat for mr2? where can i get it?

 

[xtremeleo]

the pix on the right, is a relay sir..

 

[mrtwo]

oh ok ok.yup relay..!

thanks

 

[EDDYSW20]

Superb!! Yet again, the MR2 proves to have simple fixes for a potentially chronic defect..... I think we should have a thread on them la.... chronic defects..... simple fixes..... I've got a few.....

 

[mrtwo]

aiiite..drove up to seremban to meet khoo and had a wonderful curry mee and back to kl with no problem..so that relay is the problem :)

aiite eddy why dun u start a new thread !

 

[EDDYSW20]

Yeah la.... will do la....

 

[andersen]

That is true explain " Thermostats would not have been invented if they were not needed..." and I agreed this.

But.... that is only important at Winter country and start your engine very early morning.

for mine "2" did not uses Thermostat for pass 13 years.

1st, I always start my engine after 8 am, and my engine is not a stock engine. lol
and 3SGTE engine usually could heat up very quick once your REV above 2k rpm continues for 3 to 5 minutes.

P/s: I dont even have Cool injector attach on ;-)

But stock engine is not recommended to run without thermostat, if you want run without it, you have to knew what is your act on your "2", just 2 cents ;-)

 

[EDDYSW20]

Anderson,

The thermostat is not specifically for winter or summer operation.

Please appreciate the fact that thermostat at full open does not let water flow as free as if there is no thermostat at all..... meaning your water is cooled very quick, meaning engine is cooled very quick too.

The implications of not having a thermostat is..... you have a very very cold engine block..... definitely lower than designed operating temperature, meaning after 13 years, you should have enough gunk in the valve cover and oil pan that can only be removed with crap remover..... or maybe a screwdriver!!

Try flushing your oil the next oil change, it should be fascinating.....

Just because it looks fine, do not assume all is fine...... wait till the gunk within the lines are thick enough to block the oil flow within the engine..... then all hell will break loose!!

Take care guys!!