[WTA]: Driving Habits

[huakenny]

been using turbo timer for few years on evo3 n wrx....so far no problem wit turbo....i think turbo timer did it jobs.....

how hot d oil is depends on d grade n type of motor oil u r running.....if u think ur oil is too hot...try to put an oil cooler..it helps....

Heh wanted to share with you guys, if you drive at high speeds for prolonged periods on a nice hot afternoon, next time stop just enough to shut your engine down and pull your dipstick. Mine was fuming... :) and no I was not running a turbo.

So think only turbo cars need to be cooled down before switching off?

The best explanation I can give is avoid rapid/subbden changes in temperature. If your have been speeding, wind down, slow down, rev down, WAY before you reach your planned shut off point. Thats my best advice. 5 mins of relaxed driving will probably cool your car far more than 5 mins of idling. Turbos timers are pretty ok. but I question how effective is the oil cooling when your not having air moving through your radiator and relying the fan only.

 

[evoX2]

sorry to tumpang this tread....i heard that in the morning when car engine is cold, it is not good to turn on the air con straight away, how true is it?

 

[huakenny]

sorry to tumpang this tread....i heard that in the morning when car engine is cold, it is not good to turn on the air con straight away, how true is it?

yea..im wondering same problem too......i did warm up..but with a/c On or Off?

 

[whatdamn]

hmm, good follow up with this thread. i let my car warm up in the morning about 5 mins...i notice there's a screeching sound when i turn my aircon on and rev up to 2-3k rpm while the engine is cool...this problem dissipates while engine heats up...can anyone pin-point this sound?

i usually off the air-con before shutting down the engine...regardless of hard/normal driving. anyone does this too?

 

[huakenny]

hmm, good follow up with this thread. i let my car warm up in the morning about 5 mins...i notice there's a screeching sound when i turn my aircon on and rev up to 2-3k rpm while the engine is cool...this problem dissipates while engine heats up...can anyone pin-point this sound?

i usually off the air-con before shutting down the engine...regardless of hard/normal driving. anyone does this too?

i nvr off my aircon before off engine....but off or on is better ar when off engine?

 

[evoX2]

i will off my air con whenever i off my car, n the morning i will let the car warm up "a little" then on the air con...but after morning warm up, i just on air con whenever i turn on my car.

I notice when u on air con it will drag down the rpm a little...

 

[whatdamn]

the fluctuating rpm is caused by the air con belt being switched on, so during that period of activation, some of ur engine's power is used to start the fan motor, thus causing the drop in rpm...it shouldn't drop too low though. i think there's a ticking sound too.

 

[cossie]

oil cooler

if there is no oil cooler installed, then how does the engine oil cool off in a N/A engine while it is being idled? if the engine oil is so hot that it will destroy the main bearings, blah-blah... then isn't the engine oil even hotter during 'heavy' engine operation?

i believe if the engine is going to be used for heavy duty, then an oil cooler should be fitted to aid the cooling of the engine oil so that the oil will be as cool as it can be during 'heavy' operation. idling the car without an oil cooler is not going to cool down the engine oil dramatically and the oil is kept 'warm' for a longer period of time. if 'hot' oil is bad for the engine, then the faster we turn the engine off (without an oil cooler installed), it should be better.

also engine oil has a lifespan. we use mileage (distance and time) as a gauge for its replacement time. if we're in the habit of idling our engines, the lubricant will age and lose its capabilites without leaving a record or a reading which we can comprehend. so if this is our practice, we must roll forward the time (reduce the interval) to change the engine oil. perhaps an hour of idling an engine is equivalent to 200km of driving distance.

 

[cossie]

...i notice there's a screeching sound when i turn my aircon on and rev up to 2-3k rpm while the engine is cool...this problem dissipates while engine heats up...can anyone pin-point this sound?

perhaps you need to replace the bearing on the idle pulley? or the size of the belt you are using is a little 'off-spec' or the alignment of the compressor to the rest of the pulleys are a bit off or there is a small oil leak that is dripping on the belt. some cases when the engine is warmed up, the leak is 'sealed' by expansion and after the oil on the belt is 'run-off', the screech is no longer audible.

the screeching sound is due to belt-slippage during the initial load from the compressor which is in the compression cycle.

i usually off the air-con before shutting down the engine...regardless of hard/normal driving. anyone does this too?

i try not to but it has nothing to do with protecting the engine. i'm protecting my comfort! :p

 

[cossie]

special way

sorry to tumpang this tread....i heard that in the morning when car engine is cold, it is not good to turn on the air con straight away, how true is it?

turning on the aircon, amplifiers, lamps and any other accessory will require power from the engine from extra loading from the alternator, compressor and re-charging the battery that has just been used to crank the engine. for this reason, some people feel it is better to keep the loads to a minimum while warming up the engine.

there is no harm if we treat our engine in a 'special way'. but i think the modern engine and components can cope with all these demands. if turning on all the accessories before the engine is warmed up will shut-off the engine, then i will look into the cold air-fuel mixture or other possible causes for the engine to 'mati' when i turn on some things while the engine is cold (applies to engines with ECU only). maybe something is causing too much drag elsewhere. if this is true when the engine is cold, then it will hamper the engine performance when i need the power.

 

[Boink Boink]

Oh yeah wanted to share.... I was driving this car with a factory fitted oil temp guage.

On cruie on highway speeds at about 120km/h - it showed 120 degC

On full speed runs at 190+km/h the guage showed 160degC.

When we slowed down back to our cruise. It went to 170 degC before coming back down to 120degC or so.

That said. Yep sound is your air con belt slipping. Go buy new one lor and cehck tension. but just live with the screech la, then neighbours know you going to work mar.

 

[12oY]

if there is no oil cooler installed, then how does the engine oil cool off in a N/A engine while it is being idled? if the engine oil is so hot that it will destroy the main bearings, blah-blah... then isn't the engine oil even hotter during 'heavy' engine operation?

i believe if the engine is going to be used for heavy duty, then an oil cooler should be fitted to aid the cooling of the engine oil so that the oil will be as cool as it can be during 'heavy' operation. idling the car without an oil cooler is not going to cool down the engine oil dramatically and the oil is kept 'warm' for a longer period of time. if 'hot' oil is bad for the engine, then the faster we turn the engine off (without an oil cooler installed), it should be better.

also engine oil has a lifespan. we use mileage (distance and time) as a gauge for its replacement time. if we're in the habit of idling our engines, the lubricant will age and lose its capabilites without leaving a record or a reading which we can comprehend. so if this is our practice, we must roll forward the time (reduce the interval) to change the engine oil. perhaps an hour of idling an engine is equivalent to 200km of driving distance.

if no oil cooler the engine oil still can cool by water when idled... the engine block have build in water jacket but i take time abit longer to cool down compare to those engine have oil cooler...

 

[whatdamn]

cossie,
wow very informative! am contemplating an oil cooler, however, it isn't a priority item. but thanks for the info on the screeching sound...i also noticed that once the screeching kicks in, the rpm is left constant even with revving the engine...will check with my mech on this.

 

[tajulsans]

I'm not sure bout belt slippage during cold start, i'm quite sure that its due to excessive friction between the belt and pulley.. my remedy is to apply some belt dressing or silicon spray that is available at acccesories shop, or the cheaper method is by rubbing some candle to the belt side.. my mech tells me that the reason for extra friction during cold start is because the belt have become tensioned abit as its cold, later when it has warmed up it will expend abit thus the friction disapeare loh..

 

[tajulsans]

if no oil cooler the engine oil still can cool by water when idled... the engine block have build in water jacket but i take time abit longer to cool down compare to those engine have oil cooler...

this is so true.. u must first understand the function of lubricant in internal combustion engine.. lubricating the moving parts in the engine is its main function, but it also function as heat storage that absorb heat (biproduct of combustion).. but if the heat is maintain in the engine, it will slowly increase temperature and the engine will kaboom.. thats where another heat exchanger is required and water come into the scene.. the coolant water will circulate in ur engine, absorb heat and release it to the environment via the radiator (moving air is required of course)..

then why turbo car or highly tuned car need oil cooler u may ask.. in turbo application, engine lubricant will also be used to lubricate the turbine and absorb heat from turbine (if turbine gets too hot it will also kaput maa).. since turbine is far hotter as it absorb heat from hot exhaust gasses, the lubricant temperature will increase due to storing too much heat and the coolant is not sufficient to transfer the heat.. thats why oil cooler is required, to assist the function of our good ol radiator...

by the way, the oil cooler will not do much help to cool down the engine while idling as there is no air circulation due to lack of cooling fan.. it will only help u when the car is in motion..

why do we need to cool down our engine after heavy revving.. metal part as u know expand when it gets hot, when u go high revving.. the temperature is hotter than normal driving thus metal parts expand much more.. let the temperature drop to a safer level before turning of ur engine off..

 

[tajulsans]

also engine oil has a lifespan. we use mileage (distance and time) as a gauge for its replacement time. if we're in the habit of idling our engines, the lubricant will age and lose its capabilites without leaving a record or a reading which we can comprehend. so if this is our practice, we must roll forward the time (reduce the interval) to change the engine oil. perhaps an hour of idling an engine is equivalent to 200km of driving distance.

every design in the world will have safety factor, if a normal engine oil is claimed to maintain its properties until 5000 km, then 5000km is where factor = 1.. in design u have to consider alot of other external, uncertained things that can affect the end product.. say like a young man driving vs old man driving.. driving in high way where engine temperature is maintained at higher for longer period vs town driving where temperature can fluctuate due to stop go trafic.. the lubricant will probably be designed with safety factor 2 or maybe 3 where it can withstand and maintain its properties until 10000 km or 15000 km.. this way u can endure that if the worst scenario happens and the lubricant life is shortened, it is still able to perform till 5000 km loh..

if idling is taken into consideration, i cant imagine u going to kl at peak hours or in rainy days, stuck in trafic jam, or stopping at traffic light.. turning ur engine off each and every time ur car stops just to make sure the mileage is correct :D

P/S: I was inform by my bro who is working at petronas, the mach 5, petronas cheapest oil was tested till 50,000 km and still maintain its properties..

 

[whatdamn]

thanks tajulsans!

anyone else care to share?

 

[Pickcell]

nice!! learn so many things hehee..

why dun u all cut it all short, and post the exact correct information in one post?

like.. After hard driving, N/A car should "this" before on, should "that" before off.

Turbo cars should "this" before on, and "that" before off.

:D