Engine Heat Or Lack Of It

[chamindaa]

I did a quick google search and came up with the common causes of engine overheating. In summary it can be any one of a low coolant level or a coolant leak, poor heat conductivity inside the engine because of accumulated deposits in the water jackets, a defective thermostat, poor airflow through the radiator, a slipping fan clutch, an inoperative electric cooling fan, a collapsed lower radiator hose, an eroded or loose water pump impeller, or even a defective radiator cap.

Now my question to the experts here is what happens if the engine gets too cold. Eg. If i replace my cooling fan with a little more powerful one.

Will the thermostat go bust. Given the fan is little more powerful than the previous one it need not be switched on as frequently as done previously.

What happens when the AC is on, the fans run at this time and will it make the engine colder ?

What about the HP gain or loss ?

What are the repercussions to the engine?

Now for the grand scenario. I drive a Nissan Cefiro A32 petrol version. The engine started to boil but the temperature gauge never went above the middle mark. Hooked the car to the consult and found out my low in the radiator fans were not working and was told to replace it. I found the fans from an equivalent diesel version and I replaced my faulty fans with them. Now the temp gauge is just a notch lower than the middle. The car performs well and the AC is good.

[Sumiya]

Hi Chamindaa

Remember for an engine to run smoothly it needs a level of

temparature , even if you fit more powerfull fan it will not give you

an advantage becasue if your car cooling system is functioning properly

car will come to minimum temp required to run it within 5 to 10 minutes normal driving

, if your car is runing cooler than normal temp , you may loose your fuel consumption as

well as life time of your engine

thanks

Regards

Sumith

[harshansenadhir]

Will the thermostat go bust. Given the fan is little more powerful than the previous one it need not be switched on as frequently as done previously.

What happens when the AC is on, the fans run at this time and will it make the engine colder ?

What about the HP gain or loss ?

What are the repercussions to the engine?

as fellow member replied, running too cold is not advised as there's an adverse impact towards fuel efficiency. Now, fixing a powerful fan, I assume it consumes more power than the standard. True it may cut off quicker than the previous one but it consumes high electricity means adds more load on the alternator hence engine.

if your thermostat valve is not in place, yes engine may run cooler due to the new fan provided that it runs continuously. Running on lower temp can be corrected by let the fan to operate through a thermostat switch which trigger the fan only when engine reaches working temp.

There will be slight HP loss if the fan consumes higher electricity.

[Edward]

as fellow member replied, running too cold is not advised as there's an adverse impact towards fuel efficiency. Now, fixing a powerful fan, I assume it consumes more power than the standard. True it may cut off quicker than the previous one but it consumes high electricity means adds more load on the alternator hence engine.

if your thermostat valve is not in place, yes engine may run cooler due to the new fan provided that it runs continuously. Running on lower temp can be corrected by let the fan to operate through a thermostat switch which trigger the fan only when engine reaches working temp.

There will be slight HP loss if the fan consumes higher electricity.

Hi experts,

You may remember, I wrote few weeks back some problems in my Ae 110, I got all the problems sorted out, except engine speed, I noticed the engine speed comes to normal, when the temperature is normal, but when the engine is cold the speed is more. Is this normal? Also comparing to my previous cars, this car takes more time to come to normal. My office is only 5 km,s from my home, until I reach office the temprerature is not normal. I need to drive atleast 8 to 10 km to get the normal temperature. What may be the problem?

[Miyuru Daminda]

Hi experts,

You may remember, I wrote few weeks back some problems in my Ae 110, I got all the problems sorted out, except engine speed, I noticed the engine speed comes to normal, when the temperature is normal, but when the engine is cold the speed is more. Is this normal? Also comparing to my previous cars, this car takes more time to come to normal. My office is only 5 km,s from my home, until I reach office the temprerature is not normal. I need to drive atleast 8 to 10 km to get the normal temperature. What may be the problem?

May be your thermostat valve is not properly working ( always open ) and that cause coolant to flaw through radiator even in cold start. Also check radiator fan, is it starting before engine reaches normal temperature? if yes then check your thermostat switch

[Rebel]

Hi experts,

You may remember, I wrote few weeks back some problems in my Ae 110, I got all the problems sorted out, except engine speed, I noticed the engine speed comes to normal, when the temperature is normal, but when the engine is cold the speed is more. Is this normal? Also comparing to my previous cars, this car takes more time to come to normal. My office is only 5 km,s from my home, until I reach office the temprerature is not normal. I need to drive atleast 8 to 10 km to get the normal temperature. What may be the problem?

Hi I'm no expert. I think the engine works at a higher RPM till the engine reaches operating temp and I don't think that km is adequate time for the engine to reach operating temp.

Anyways best to wait for the experts to reply

[Mani]

Hi experts,

You may remember, I wrote few weeks back some problems in my Ae 110, I got all the problems sorted out, except engine speed, I noticed the engine speed comes to normal, when the temperature is normal, but when the engine is cold the speed is more. Is this normal? Also comparing to my previous cars, this car takes more time to come to normal. My office is only 5 km,s from my home, until I reach office the temprerature is not normal. I need to drive atleast 8 to 10 km to get the normal temperature. What may be the problem?

Biggest culprit would be a stuck open Thermostat valve. The whole purpose of the Thermostat is to regulate engine temperature. As such, if the valve is stuck open, it will not allow the engine to be brought up to temperature quickly assuming your gauge is functioning properly.

chamindaa, your problem could be the opposite of the above assuming the rest of your cooling system is free of foreign matter buildup.

Inspect the cooling system to make sure no hard water build up is present. Inspect the Thermostat for proper function.

Lastly, in SL you don't need the 50/50 coolant to water ratio. You can go to 80/20 in favor of more water than coolant . You only need enough coolant to lubricate the water pump. Water does a much better job of conducting heat than coolant. 50/50 ratio is critical only if the environment the vehicle operate is cold, as in freezing temperatures.

Good luck to both of you.

Edited June 23, 2009 by Mani