Do cooling fans loose much efficiency over time?
#1
Do cooling fans loose much efficiency over time?
I have had constant cooling issues with my XJR which, I suspect, led to a blown gasket a couple of years ago. Anyway, she still seems to run on the hotter side compared with the numerous reports I've seen in multiple threads here. Over the past few years I've had everything replaced in my cooling system - radiator, thermostats, hoses, expansion tank, water pump etc. She gets very hot in heavy traffic or climbing steep, long gradients (mountains) - get's very close to 221°F (105°C).
The two things I wonder about, usually in the small hours when I can't sleep, are:
1) My original cooling fans might not be nearly as efficient as they used to be? I wonder how much cooling ability they actually loose?
2) Maybe my aftermarket brass radiator is not very good? (8 years old, reconditioned 12 months ago)
The two things I wonder about, usually in the small hours when I can't sleep, are:
1) My original cooling fans might not be nearly as efficient as they used to be? I wonder how much cooling ability they actually loose?
2) Maybe my aftermarket brass radiator is not very good? (8 years old, reconditioned 12 months ago)
#2
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#4
The replacement fans cost USD$964, so not something I want to jump into if it's not going to make a difference.
#5
I can't imagine the fans even existing make much difference if you're moving at a reasonable speed so there's airflow through the rad.
I'd be suspecting the non-standard rad doesn't allow as much coolant and/or airflow resulting in it removing less heat from the cooling system.
I'd be suspecting the non-standard rad doesn't allow as much coolant and/or airflow resulting in it removing less heat from the cooling system.
#6
Ahh, I hadn't seen you mention traiffic, apologies if I missed it. I know the fan control gubbins has high & low speeds for each fan. No idea if it'd throw codes if the high speed isn't working, but that has to be worth a look if you've not already done so? I've seen diagnostic instructions on this forum before. From what I recall it goes off engine temp AND AC pressure rather than simple thermoswitches in the rad.
#7
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#8
While looking over this thread, I imagined your issues and what methods I might
attempt to determine the cause/s. If my radiator was ascertained to be circulating
the coolant and my fans were cycling on and off as intended, what would I check
next? The thought occurred that perhaps the water pump was not circulating the
coolant at the proper rate, or that the thermostat was not operating as intended.
I remember an SS396 where the thermostat would occasionally stick, and cause
it to overheat which took me a while to pinpoint.
attempt to determine the cause/s. If my radiator was ascertained to be circulating
the coolant and my fans were cycling on and off as intended, what would I check
next? The thought occurred that perhaps the water pump was not circulating the
coolant at the proper rate, or that the thermostat was not operating as intended.
I remember an SS396 where the thermostat would occasionally stick, and cause
it to overheat which took me a while to pinpoint.
#9
actually 221*F isn't that bad when crawling in traffic. Coolant will raise the boiling temp, so will pressurization. So you do not appear to be closing to boiling over.
Need to check to see if both fans are working; are you getting any knocking climbing grades? Using high test gas?
Maybe change the coolant and drive . . .
Need to check to see if both fans are working; are you getting any knocking climbing grades? Using high test gas?
Maybe change the coolant and drive . . .
#10
I have an s type r. Same engine and cooling pack. Every two years i take off the bumper cover and hose out everything. It makes a nice difference. If you want to diagnose an easy way is to get a cheap box fan. They are easier to get to grill height. Take a drive to get warmed up then park in driveway or near an elec outlet. Leave in park and put the fan on full in front of the grill. If you get a nice temp drop then your engine fan may be suspect. If not then probable debris in cooling stack. The radiator is the last in line to get the airflow so the intercooler and condensor need to be clean as possible. An outlier would be high condensor temps when using ac but that would also affect ac performance. Just noticed you have 2001 xjr. Should be same cooling arrargement but i dont know about engine
Last edited by scottjh9; 08-26-2024 at 01:40 PM.
#11
A coolant line flush with filtered water and ran without the T-stat 50 miles, heater matrix on open on hot! Evenings best.
Check the whine of the intercooler pump with ignition on.
Fresh 50/50 orange Ford spec coolant mix and a good old burp, or vac fill.
A new T-stat, and blast outside the other coolers behind the grills with compressed air if possible, jet washing with a bit of care might clear debris.
(You checked for no lines crossed?)
I used to commute in my R and on a good few occasions ran it into the both fans on high speed, which are very efficient if the bonnet is popped. It needs to be all working well in high temps for a happy engine.
I did notice Shell V-Power gave the engine a better protection from pulling timing. It should be fine in high road temp traffic.
The RealGauge offered by our forum member is a great tweak.
https://www.thejagwrangler.com/xk8--...realgauge.html
Check the whine of the intercooler pump with ignition on.
Fresh 50/50 orange Ford spec coolant mix and a good old burp, or vac fill.
A new T-stat, and blast outside the other coolers behind the grills with compressed air if possible, jet washing with a bit of care might clear debris.
(You checked for no lines crossed?)
I used to commute in my R and on a good few occasions ran it into the both fans on high speed, which are very efficient if the bonnet is popped. It needs to be all working well in high temps for a happy engine.
I did notice Shell V-Power gave the engine a better protection from pulling timing. It should be fine in high road temp traffic.
The RealGauge offered by our forum member is a great tweak.
https://www.thejagwrangler.com/xk8--...realgauge.html
Last edited by Sean B; 08-26-2024 at 03:26 PM.
#12
While looking over this thread, I imagined your issues and what methods I might
attempt to determine the cause/s. If my radiator was ascertained to be circulating
the coolant and my fans were cycling on and off as intended, what would I check
next? The thought occurred that perhaps the water pump was not circulating the
coolant at the proper rate, or that the thermostat was not operating as intended.
I remember an SS396 where the thermostat would occasionally stick, and cause
it to overheat which took me a while to pinpoint.
attempt to determine the cause/s. If my radiator was ascertained to be circulating
the coolant and my fans were cycling on and off as intended, what would I check
next? The thought occurred that perhaps the water pump was not circulating the
coolant at the proper rate, or that the thermostat was not operating as intended.
I remember an SS396 where the thermostat would occasionally stick, and cause
it to overheat which took me a while to pinpoint.
#13
actually 221*F isn't that bad when crawling in traffic. Coolant will raise the boiling temp, so will pressurization. So you do not appear to be closing to boiling over.
Need to check to see if both fans are working; are you getting any knocking climbing grades? Using high test gas?
Maybe change the coolant and drive . . .
Need to check to see if both fans are working; are you getting any knocking climbing grades? Using high test gas?
Maybe change the coolant and drive . . .
Maybe I'm just being paranoid after dealing with a 2 year period of overheating and coolant loss that resulted in a blown head gasket - I started to get obsessed with monitoring the coolant temp (OBD2) all the time.
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#16
You can test the X308 cooling fans that they both come on to highest mode
On the X308 it does have a similar fan control relay module to control both fans which in turn is commanded by the engine ECM
You should have a coolant temp sensor ( and not a temp switch as in the X300 ) that can be removed and tested with a hot water bath )
The target temps on the X300 inline 6 engine are low mode 86 C and high mode100 C
You need to confirm that both fans run high at your engine's high need
Just need to see high mode
The fan relay control module can be mounted upside down , connector has to be on the bottom
The power contacts inside ( sealed ) can be corroded not delivering the current to properly power the fan motors
Both these fan motors have a ground terminal somewhere
On my X300 , it was full of water as mounted connector side up
Your X308 fan relay control is black in color and not white for the X300
There is a coolant hose misroute the Motorcarman has seen plenty of and has the details
Module location under car left front wheel
On the X308 it does have a similar fan control relay module to control both fans which in turn is commanded by the engine ECM
You should have a coolant temp sensor ( and not a temp switch as in the X300 ) that can be removed and tested with a hot water bath )
The target temps on the X300 inline 6 engine are low mode 86 C and high mode100 C
You need to confirm that both fans run high at your engine's high need
Just need to see high mode
The fan relay control module can be mounted upside down , connector has to be on the bottom
The power contacts inside ( sealed ) can be corroded not delivering the current to properly power the fan motors
Both these fan motors have a ground terminal somewhere
On my X300 , it was full of water as mounted connector side up
Your X308 fan relay control is black in color and not white for the X300
There is a coolant hose misroute the Motorcarman has seen plenty of and has the details
Module location under car left front wheel
Last edited by Parker 7; 08-27-2024 at 02:23 AM.
#17
#20
Thanks for the reference , do you have a link ( for the library ) other than what you had as this takes me to an advertisement
I do not have the X308
Quality known brand fuses ( or swap with the like cabin blower fans ) would be a cheap try other that a load test lamp on the fans or purchasing anther fan control relay module
There are 2 fuses in the system
Will be at dialysis center for a while becoming one with my purity
I do not have the X308
Quality known brand fuses ( or swap with the like cabin blower fans ) would be a cheap try other that a load test lamp on the fans or purchasing anther fan control relay module
There are 2 fuses in the system
Will be at dialysis center for a while becoming one with my purity