Preventive maintance or not?

[NSXFRIEND]

I am not experiencing any runability issues but as a preventative measure I noticed a few individuals have run a wire or toggle switch to the radiator fan to make it run all the time when the car is running. Is this a necessary preventive measure for a weekend driver?

At what temperature or time should the radiator fan turn on?
If the fan in the engine bay cools the engine what is the other function of the radiator fan? I know the A/C has its own fans.



Thanks

 

[Briank]

The fan cools the coolant which cools the engine. the engine bay fan is mostly useless and was dropped in later cars. The radiator fan turns on at a low speed at 172 degrees and goes to high speed at 183 degrees. There is really no reason to install a manual switch unless you are trying to work around a problem with the stock control system.

 

[LS1toNSX]

the engine bay fan is mostly useless and was dropped in later cars.

Oh wow! Thats a cool bit of trivia. Maybe the fan might help preserve the life of the engine bay hoses and belts a little, but Honda must have dropped it for a reason.

 

[goldNSX]

Oh wow! Thats a cool bit of trivia. Maybe the fan might help preserve the life of the engine bay hoses and belts a little, but Honda must have dropped it for a reason.

This had been discussed several times here before. The engine bay fan has been removed by Honda and so do many owners on early cars as it very very rarely gets on.

 

[NSXFRIEND]

After reading about NSX's overheating in this thread, and being a perfectionist/ADD

http://www.nsxprime.com/forums/showthread.php?t=48505

I thought it would be wise to keep the fan running at all times for longevity. I know this only applies to tracked cars but nevertheless added security is nice.

Most Porsche people add external oil coolers and now water coolers for summer days. I know the NSX has a small oil cooler and being mid-engine cool air is important.

This is also interesting thread modified engine bay fan to keep trunk cool.lol
Since the fan was deleted on later models was anything added?

http://www.nsxprime.com/forums/showthread.php?t=56305

 

[Briank]

The NSX is not a Porsche so things people do to Porsche's have no relationship to what might be done for cooling on an NSX.

If it ain't broke don't fix it applies here.

After reading about NSX's overheating in this thread, and being a perfectionist/ADD

The NSX is a very well designed car "near perfection some would say" and will run in its stock operating condition nearly forever and even cars that are tracked run fine with the stock cooling system. Messing with the fans on a stock car has no benefit and will not increase you securty. Running the fans when not required is just anouther load on the electricial system which is powered by the engine so you give up horse power which could be used to move the car down the road.

http://www.nsxprime.com/forums/showthread.php?t=56305 is a thread on keeping a PC cool in the trunk. Most of the heat in the trunk comes from the exaust system right below it and not the engine bay.

 

[NSXFRIEND]

The NSX is not a Porsche so things people do to Porsche's have no relationship to what might be done for cooling on an NSX.

If it ain't broke don't fix it applies here.



The NSX is a very well designed car "near perfection some would say" and will run in its stock operating condition nearly forever and even cars that are tracked run fine with the stock cooling system. Messing with the fans on a stock car has no benefit and will not increase you securty. Running the fans when not required is just anouther load on the electricial system which is powered by the engine so you give up horse power which could be used to move the car down the road.

http://www.nsxprime.com/forums/showthread.php?t=56305 is a thread on keeping a PC cool in the trunk. Most of the heat in the trunk comes from the exaust system right below it and not the engine bay.

I agree the NSX is amazing and I see your point about adding load on the electric. What Porsche or Ferrari does is usually as a result of its mid/rear-engine profile which requires additional cooling since there is no frontal air directed to the motor. After all NSX/Porsche/Ferrari were made to be tracked and if so it should hold up and not everheat. These cases of overheating maybe incidental and not in relation to the nature of the car. I recall the Type R racing overheating in best motoring. The NSX was tested at nordschleife and tochigi for quiet a while before going public, infact one could argue 911 is the modeled car the NSX was targeting. I wonder if any other variable is causing these few cars to overheat.

 

[L8apex32]

NSXes don't have much trouble with overheating. Mine did (past tense) becuase the radiator fins were munged after 140k miles of use. With a new radiator, no trouble.

Also, fans behind radiators are only useful in city driving. Cars on the track have much more air going through the radiator(s) than a fan can move. A race car would be likely to delete the radiator fan than to add one.

 

[Briank]

What Porsche or Ferrari does is usually as a result of its mid/rear-engine profile which requires additional cooling since there is no frontal air directed to the motor.

Cooling of the motor from air flow around it is miniscule compared to the amount of heat that needs to be dissipated. So a front location has no benefit over a mid-engine in direct cooling of the engine. Not to mention the engine is not a radiator. Location of and air flow through the radiator is a major factor and coolant flow between the engine and radiator is the other on how a cooling system performs. Mid-engine cars can be harder to cool because of the distances involved getting the coolant from the engine to the radiator and the losses involved in moving the coolant through the extra plumbing.

 

[goldNSX]

Mid-engine cars can be harder to cool because of the distances involved getting the coolant from the engine to the radiator and the losses involved in moving the coolant through the extra plumbing.

Yes, they're more difficult in mid-engines but the cooling system on the NSX is well designed as long as it's well maintained.

Adding to this: The major problem with mid-engine colling system is their complexity and possibility of small leaks like o-rings and gaskets. See Wolfgang's post http://www.nsxprime.com/forums/showthread.php?t=48505 from post #111 on (Gerard). He lost pressure in the system just because of a ridiculous $0.01 O-ring. So it's no waste of money to revise the complete cooling system after 10+ years if you NEED the full cooling capability.

Adding a blower to the system won't help much because the cooling efficiency of water is much higher than the one of air. So being a perfectionist (like I try to be too :wink would be better to give the cooling system a revise.

 

[hofffam]

My 97 runs perfectly cool even in hot Texas temperatures. My car ran too COOL in the winter because of a failed thermostat. It seems NSX thermostats fail "open" instead of "closed."

 

[goldNSX]

My 97 runs perfectly cool even in hot Texas temperatures. My car ran TOO cool in the winter because of a failed thermostat. It seems NSX thermostats fail "open" instead of "closed."

I wouldn't be sure of that. I've heard both stories about the thermostat.

 

[hofffam]

I wouldn't be sure of that. I've heard both stories about the thermostat.

Maybe so. But while I searched on thermostat threads it seemed most were being replaced because the rubber piston seal had failed, allowing coolant to circulate at all times. Definitely what was wrong with mine.

The thermostat on my Jag S-type, unfortunately failed twice, in the other way. Overheating of course results.

 

[davidf]

Well that just bites. And here I replaced the radiator and radiator cooling fan motor as another precautionary, and now you say it's not really a necessity.:frown: My car only has 53000 but at 16 years old, I want it mechanicly as perfect as possible.

 

[Larry Bastanza]

I am not experiencing any runability issues but as a preventative measure I noticed a few individuals have run a wire or toggle switch to the radiator fan to make it run all the time when the car is running. Is this a necessary preventive measure for a weekend driver?

The is unnecessary.

At what temperature or time should the radiator fan turn on?
If the fan in the engine bay cools the engine what is the other function of the radiator fan? I know the A/C has its own fans.

The fans run at two speeds based on the engine temp sensor output and the A/C system pressure.

They come on at 84C and go off at 78C in low speed mode
They come on at 90C and go off at 84C in high speed mode

The engine bay fan is USELESS.

This is all managed by the Cooling Fan Control Unit located on the rear bulkhead behind the seats.

HTH,
LarryB

PS: Dave, you have too much money.
You can stop replacing good parts now, its OK.

 

[Big_D]

PS: Dave, you have too much money.
You can stop replacing good parts now, its OK.

LOL

I know, its easy to get carried away when trying to do preventative maintenance.

 

[davidf]

Huge thanks Larry. I'm embarassed to say fan cooling control unit is replaced also. :redface: The spending stops today. I guess theres is such a thing as loving your car too much.

 

[davidf]

So would you recommend removing the rad. fan assm. or just leave it all alone?

 

[davidf]

Delete that.