Temperature Issue

[Accord80]

Driving a Myvi BOT an I have this problem. After driving for some long time (2 hour+++) and stop, the temperature is rising. But, the temp will going down after drive back. Same thing also happen when driving from home to office (around 4-5 days). FYI, the head has been PnP to the max, got alu radiatior and run without thermostat. The fan is in good condition. Went for pressure test, it shows okay. What does it mean? Do I need to install an oil cooler?

 

[DanzEterna]

y did u remove your thermosthat? its there for a reason.

 

[Accord80]

Ermm....just do it according to my mech. FYI, I'm still new to turbo coz playing NA for a long time. But since this is happened (overheating) I decided to put back and still monitoring. If someone with experience can help me with these...

 

[DanzEterna]

maybe your fan not powerful enuf...do check it as well....
try to use water wetter...might decrease your water temp abit.

 

[judean]

i noticed dat some ppl like to remove their themostat...
n normally their reason is so dat their engine wud always in a low temp condition...
can anyone clarify on this...?
logically n theoretically to me it seems like it can be done...
but juz like bro danzeterna said...
it's there for a reason rite...?

 

[DanzEterna]

well im not sure bout that but im definately not removing mine, alternatively there are sports thermosthats available though.

 

[^pomen_GTR^]

well...i suspect the aluminium rads not have enough cooling capacity....



p/s:copper rads better than some aluminium rads

 

[Accord80]

Well, let's think from a negative side. Can it be the head warped?

 

[turbolover]

i noticed dat some ppl like to remove their themostat...
n normally their reason is so dat their engine wud always in a low temp condition...
can anyone clarify on this...?
logically n theoretically to me it seems like it can be done...
but juz like bro danzeterna said...
it's there for a reason rite...?

Petrol powered car needs to operate on an optimal operating temperature. Having the thermostat on all the time with the temp lower than usual will cause higher fuel consumption also.

 

[Ashyie_Ferio]

thermostat turns the radiator fan on when a certain temperature is reached i believe. correct me if im wrong.

 

[huakenny]

Thermostat valve open at certain temp degree to allows water to flow from engine to radiator........without thermostat mean ur water in cooling system is flowing all the time...that y the temp is low

If ur temp going up when idling(car x moving) and going down when moving....mostly is the fan issue....but not sure,u hv to double check d fan...add one more fan better

 

[jeremylj]

Driving a Myvi BOT an I have this problem. After driving for some long time (2 hour+++) and stop, the temperature is rising. But, the temp will going down after drive back. Same thing also happen when driving from home to office (around 4-5 days). FYI, the head has been PnP to the max, got alu radiatior and run without thermostat. The fan is in good condition. Went for pressure test, it shows okay. What does it mean? Do I need to install an oil cooler?

You mentioned tempreature will rise, how did you monitor it? External water tempreature meter? Or using your original meter? If external meter, how much is the range.? Have you checked the water level inside the radiator when cold? (Not the reserve tank)

 

[jimmyae101]

check coolant too...check any leak from water pump,raidator.....

 

[DanzEterna]

if head warped then when driving temp will rise immediately

 

[Izso]

Like what Pomen GTR said, Alu rads are not actually as efficient as copper rads. The only advantage alu has over copper is that it doesn't rust and most of the time aftermarket alu rads are made bigger so their surface area is larger. You're better off with a 2/3 layer copper rad imho.

Engine oils run at their optimum viscousity at 100 degrees celsius. So if you take out the thermostat it'll take the oil much longer to reach optimum viscousity and what does that mean? It means your engine is not getting the proper lubrication for a longer period of time. And why is that important? 90% of all engine damage occurs at cold startup. So if it's cold longer, more engine damage. We're not talking catestrophic breakdown here, just faster wear and tear of the piston rings, valves, bearings and generally most metal bits and pieces inside the engine.

In this BOT overheating case - can I ask if you are using oversized pistons? Or did you just plug and play K3VET low comp pistons? I suggest you change your radiator cap as well as the thermostat to an aftermarket thermostat. It sounds like it's not opening early enough to compensate for the larger heat the BOT is causing. Either that or your radiator is not getting enough air. Some Myvi bodykits are very restrictive and what some people do is drill holes in the front chassis bit that's blocking the radiator.

 

[turbolover]

Izso, What happens if one uses oversized piston? What are the consequence and how will it affect the temperature?

 

[mines998]

Perhaps your head gasket not fitted properly.

 

[Slowboy]

What ecu you are using? Certain aftermarket ecu have different setup for fan controller. If that is a prob, try to find an aftermarket fan controller

 

[D7zul]

Thermostat is there for a reason..

and the reason is to control devices so that the system's temperature is maintained near a desired setpoint temperature

in other words.. the optimum temperature for an engine or anything else

read this

Thermostat - Wikipedia, the free encyclopedia@@AMEPARAM@@/wiki/File:Honeywell_round_thermostat.jpg" class="image"><img alt="" src="http://upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Honeywell_round_thermostat.jpg/220px-Honeywell_round_thermostat.jpg"@@AMEPARAM@@commons/thumb/4/4c/Honeywell_round_thermostat.jpg/220px-Honeywell_round_thermostat.jpg

 

[Izso]

Izso, What happens if one uses oversized piston? What are the consequence and how will it affect the temperature?

Nothing's wrong la. Just depends on how much oversized. Cuz the alu block for the K3VE is very thin already so overboring it will make the pistons damn close to the water jacket and that in turn will heat up the water much quicker than usual.

 

[upontheriversky]

Nothing's wrong la. Just depends on how much oversized. Cuz the alu block for the K3VE is very thin already so overboring it will make the pistons damn close to the water jacket and that in turn will heat up the water much quicker than usual.

oh thats good to know. good info!

 

[turbolover]

Nothing's wrong la. Just depends on how much oversized. Cuz the alu block for the K3VE is very thin already so overboring it will make the pistons damn close to the water jacket and that in turn will heat up the water much quicker than usual.

Oh I see. Cos I bought a converted 4g63 with a 86mm pistons a while back that's why i ask. Thanks for the info.

 

[Izso]

86mm on a 4G63 I think is still do-able. I *think* that's probably still safe! Gotta go look back at the manuals again. But I do know the K3VE alu block can't take more than 2mm increase and if not mistaken the 2mm increase is already pushing it. Need pretty strong sleeving and a thermostat that opens earlier, or perhaps can try using those pure coolants (no water mix).

Anyway, where did the TS go? Has he resolved the overheating issue?

 

[D7zul]

if the thermostat & a big radiator is in place but still overheat, mayb he needs an oil cooler..

i think Izso can help DIY that

 

[Izso]

if the thermostat & a big radiator is in place but still overheat, mayb he needs an oil cooler..

i think Izso can help DIY that

Haha! Easy la that one! If the the fella wants to install a oil cooler and has bought all the bits and pieces I will go to his place and document the DIY install!