Y62 Operating temps

Printable View

1st March 2025, 07:42 AM
hsbashraf

Y62 Operating temps

I have a Y62 Nissan Patrol with the VK56DE (320hp) engine, GCC spec. Recently, I installed headers, a high-flow exhaust, and a new intake. After these modifications, I took the vehicle for a full tune-up, including a dyno tune with an ECU flash.

I was experiencing overcooling issues and found that my thermostat was damaged. I replaced it with an OEM 82°C thermostat. However, after the replacement, the engine temperature at idle or in traffic now rises to 98°C (with ambient temperatures between 18-28°C). The fan never produces a roaring sound, but the temperature drops slightly after reaching 98°C. On the highway, the engine runs at 89-90°C.

I replaced the fan clutch, but it made no difference. My tuner believes these temperatures are too high and are causing performance loss. I would like to know the normal operating temperature range for the VK56DE engine. Additionally,considering patrol fan is ECU controlled, should the fan behave like a typical viscous fan, roaring at startup and locking up as the engine reaches operating temperature? Currently, I can easily turn the fan by hand, even when the engine is at operating temperature.

For reference, during a dune bashing session, engine temperatures stayed around 90-95°C. Any insights or recommendations would be greatly appreciated.
2nd March 2025, 11:30 PM
hsbashraf

Any help people
3rd March 2025, 10:05 AM
mudnut

Quote:

Originally Posted by hsbashraf

I have a Y62 Nissan Patrol with the VK56DE (320hp) engine, GCC spec. Recently, I installed headers, a high-flow exhaust, and a new intake. After these modifications, I took the vehicle for a full tune-up, including a dyno tune with an ECU flash.

I was experiencing overcooling issues and found that my thermostat was damaged. I replaced it with an OEM 82°C thermostat. However, after the replacement, the engine temperature at idle or in traffic now rises to 98°C (with ambient temperatures between 18-28°C). The fan never produces a roaring sound, but the temperature drops slightly after reaching 98°C. On the highway, the engine runs at 89-90°C.

I replaced the fan clutch, but it made no difference. My tuner believes these temperatures are too high and are causing performance loss. I would like to know the normal operating temperature range for the VK56DE engine. Additionally,considering patrol fan is ECU controlled, should the fan behave like a typical viscous fan, roaring at startup and locking up as the engine reaches operating temperature? Currently, I can easily turn the fan by hand, even when the engine is at operating temperature.

For reference, during a dune bashing session, engine temperatures stayed around 90-95°C. Any insights or recommendations would be greatly appreciated.

Welcome to the forum. Did you test the thermostat before installing it?
3rd March 2025, 05:53 PM
hsbashraf

Quote:

Originally Posted by mudnut

Welcome to the forum. Did you test the thermostat before installing it?

Thank you for the response. I actually did not test it since it was new OEM part I considered it as good. Do you think this fan behavior is normal what i explained.
3rd March 2025, 06:18 PM
Plasnart

Did you see the request to put up an intro? This is not Facebook. You will get so much more detail if you just be a normal human.
3rd March 2025, 07:15 PM
hsbashraf

Quote:

Originally Posted by Plasnart

Did you see the request to put up an intro? This is not Facebook. You will get so much more detail if you just be a normal human.

What Intro?
3rd March 2025, 08:00 PM
mudnut

This link for intro. https://www.nissanpatrol.com.au/foru...-Introductions

Over the years I've had a couple of brand new thermostats fail. I hope a Y62 owner can answer your question.
3rd March 2025, 08:37 PM
hsbashraf

Quote:

Originally Posted by mudnut

This link for intro. https://www.nissanpatrol.com.au/foru...-Introductions

Over the years I've had a couple of brand new thermostats fail. I hope a Y62 owner can answer your question.

Introduction done. Dont you think if thermostat is bad the fan should be roaring when engine is going above the set temps?
3rd March 2025, 08:40 PM
PeeBee

@MudRunnerTD, any thoughts after your performance upgrades?
3rd March 2025, 10:31 PM
Plasnart

Holy farrk.. headers done, new exhaust, intake changed, thermostat changed, fan clutch changed, now it’s misbehaving with temps. Why are people so shocked when their motor cracks the shits after being fucked around with? Why are you doing all this to a proven and reliable V8 grunt god? Keep it simple stupid. How many times do I have to say this? What are you trying to build?

Yes the VK56DE fan roars on startup. That is normal. Read your user manual as to the ECU engine startup sequencing, and don’t frig around with a proven donk (although I did put a nice cat-back exhaust on mine for the tunes!) lol
3rd March 2025, 10:49 PM
Plasnart

This motor also runs 4 X O2 sensors. The front 2 control engine tuning. So if you’ve replaced your headers you’ll need to recalibrate your front O2 sensors. The rear O2 sensors are just advisory and have no input into engine management.
4th March 2025, 12:57 AM
hsbashraf

Quote:

Originally Posted by Plasnart

Holy farrk.. headers done, new exhaust, intake changed, thermostat changed, fan clutch changed, now it’s misbehaving with temps. Why are people so shocked when their motor cracks the shits after being fucked around with? Why are you doing all this to a proven and reliable V8 grunt god? Keep it simple stupid. How many times do I have to say this? What are you trying to build?

Yes the VK56DE fan roars on startup. That is normal. Read your user manual as to the ECU engine startup sequencing, and don’t frig around with a proven donk (although I did put a nice cat-back exhaust on mine for the tunes!) lol

I dont remember asking your opinion on what to do with my V8. If you can answer the question answer it or move on. Be respectful.
All mods are support mods for better breathing in the desert heat. There is nothing fucking around with the engine unless you put a blower on it and start pushing more power. That roar is mot there may be tuner messed up with the fan speed chart. My only question was what are the normal operating temps for y62.
4th March 2025, 01:05 AM
hsbashraf

Quote:

Originally Posted by Plasnart

This motor also runs 4 X O2 sensors. The front 2 control engine tuning. So if you’ve replaced your headers you’ll need to recalibrate your front O2 sensors. The rear O2 sensors are just advisory and have no input into engine management.

The only reason for a tune was to fix the AFR. The O2 sensor are working within normal range.
4th March 2025, 09:35 AM
Plasnart

Quote:

Originally Posted by hsbashraf

The only reason for a tune was to fix the AFR. The O2 sensor are working within normal range.

Good. Move along then.
4th March 2025, 05:21 PM
pollenface

why are you being a dick, he's just asking a simple question.

If I had a y62 I'd give a better answer, but I typically see 92-95c up hills and 87-89c around town with a 3.0L CR
4th March 2025, 06:25 PM
hsbashraf

Quote:

Originally Posted by pollenface

why are you being a dick, he's just asking a simple question.

If I had a y62 I'd give a better answer, but I typically see 92-95c up hills and 87-89c around town with a 3.0L CR

Thank you. For me it is other way around. Pushing full throttle on dunes temps are 92-93, in traffic it goes up to 98c than comes down 93-95 and keeps cycling.
5th March 2025, 07:31 AM
PeeBee

Quote:

Originally Posted by hsbashraf

Thank you. For me it is other way around. Pushing full throttle on dunes temps are 92-93, in traffic it goes up to 98c than comes down 93-95 and keeps cycling.

I dont see any issue with this variance, its completely normal. If the numbers were 120 degC, yes you have a problem. The temps will rise as a function of the energy you are putting into your 'system'. A typical radiator will shed 10 - 14 deg across the core. If the ambient temps are high the efficiency drops in the heat transfer. Whilst the engine is running high speed , on the dunes you have airflow stripping away the heat. In traffic, you are reliant on the fan to suck air over the coil, and you are stationary so the efficiency goes down. Add an a/c heat load and the numbers increase. Heat can be dissipated by conduction radiation and convection. Tine bay effectively like when moving, so you end up adding the heat to the already hot engine bay, and it becomes a heat dump. As stated above the best heat transfer sitation is when the air temps are far apart, such as 1 degC air temp and 40 degC air temp , but when the car is stationary, the block temp could be 150degC , the water is 95degC, and this pushes the water temps up, and the little radiator with the heat load from the a/c and ambient temps of 40 degC say, you run the system on the limit. Anyway, in summary, if it isn't boiling and blowing radiator hoses and caps and sitting where you say it is, I dont think its a problem.
6th March 2025, 03:06 AM
hsbashraf

Quote:

Originally Posted by PeeBee

I dont see any issue with this variance, its completely normal. If the numbers were 120 degC, yes you have a problem. The temps will rise as a function of the energy you are putting into your 'system'. A typical radiator will shed 10 - 14 deg across the core. If the ambient temps are high the efficiency drops in the heat transfer. Whilst the engine is running high speed , on the dunes you have airflow stripping away the heat. In traffic, you are reliant on the fan to suck air over the coil, and you are stationary so the efficiency goes down. Add an a/c heat load and the numbers increase. Heat can be dissipated by conduction radiation and convection. Tine bay effectively like when moving, so you end up adding the heat to the already hot engine bay, and it becomes a heat dump. As stated above the best heat transfer sitation is when the air temps are far apart, such as 1 degC air temp and 40 degC air temp , but when the car is stationary, the block temp could be 150degC , the water is 95degC, and this pushes the water temps up, and the little radiator with the heat load from the a/c and ambient temps of 40 degC say, you run the system on the limit. Anyway, in summary, if it isn't boiling and blowing radiator hoses and caps and sitting where you say it is, I dont think its a problem.

I think you are right. The last time on dunes i pushed the engine but temps never went above 94-95 c even on full throttle, and i also heard a brief fan roar may be 3,5 seconds tops. This seems to me Nissan way of doing things with the ECM controlled fan. Will see how it operates in summer heat since currently ambient temps are at 20-30c.

I would love an input from y62 owner on the normal temps.
8th March 2025, 08:56 AM
hsbashraf

I have left the vehicle on idle the fan always turns on at 98c. I dont think 98 c is normal at idling in ambient temps at 20c. I am going to tuner to return ecu to stock. I think tuner messed up the Cooling Fan graph.
9th March 2025, 06:52 PM
hsbashraf

Quote:

Originally Posted by hsbashraf

I have left the vehicle on idle the fan always turns on at 98c. I dont think 98 c is normal at idling in ambient temps at 20c. I am going to tuner to return ecu to stock. I think tuner messed up the Cooling Fan graph.

Update: the ECU was returned to stock but it made no difference. Now if hold the fan i can hold is no resistance. Even with temps at 99,100c. The fan is barely spinning if i let it go. But strangely if i restart the vehicle the fan starts to run on full speed…. I am lost here…
9th March 2025, 07:46 PM
Plasnart

I say nuffink.
10th March 2025, 12:38 AM
hsbashraf

Quote:

Originally Posted by Plasnart

I say nuffink.

What are you trying to say.
15th March 2025, 12:30 PM
MudRunnerTD

Quote:

Originally Posted by hsbashraf

Update: the ECU was returned to stock but it made no difference. Now if hold the fan i can hold is no resistance. Even with temps at 99,100c. The fan is barely spinning if i let it go. But strangely if i restart the vehicle the fan starts to run on full speed…. I am lost here…

What year and series is your Y62? I assume you are in the UAE because of the mention of desert.

What is the factory water temp guage showing? If it's in the normal range I would not be super concerned.

The Series 5 (and maybe earlier models) has a know fault with the viscous fan, the fault has them locking up though. You said you replaced the viscous though yeah?

Surely your Tuner can shed some light on it. If he doesn't know then maybe he shouldn't be tuning it?
16th March 2025, 07:13 AM
hsbashraf

Quote:

Originally Posted by MudRunnerTD

What year and series is your Y62? I assume you are in the UAE because of the mention of desert.

What is the factory water temp guage showing? If it's in the normal range I would not be super concerned.

The Series 5 (and maybe earlier models) has a know fault with the viscous fan, the fault has them locking up though. You said you replaced the viscous though yeah?

Surely your Tuner can shed some light on it. If he doesn't know then maybe he shouldn't be tuning it?

Thank you for your response. My vehicle is a 2016/06 model, but I’m not sure about the series. I am located in the GCC, specifically Saudi Arabia.

I recently replaced the fan, and the old one wasn’t locked up—the only issue was that it would start pulling air only when the coolant temperature reached 98°C. The new fan is behaving exactly the same way. However, the difference is that there’s no “roar” at startup which used to there before i started playing around with vehicle. It only locks up at 98°C and immediately slows down when the temperature drops to 95°C. The needle goes slightly up the normal notch (2nd notch) when temps are at 98C.

I also replaced the thermostat with a low-temperature one, and now, on the highway, the coolant temperature stays between 78-84°C. According to my tuner, there is no available tuning parameter for the fan speed in this model, although the platinum-spec (400hp) version does have that option. I even returned the ECU to stock, but there was no difference.
There is no overheating despite alot of dune driving in low gear.

Now, I’m considering installing two electric fans in front of the condenser that I can turn on manually when needed.i would prefer the simple mechanical fan over this contraption from Nissan.
8th April 2025, 11:46 PM
MudRunnerTD

Quote:

Originally Posted by hsbashraf

Thank you for your response. My vehicle is a 2016/06 model, but I’m not sure about the series. I am located in the GCC, specifically Saudi Arabia.

I recently replaced the fan, and the old one wasn’t locked up—the only issue was that it would start pulling air only when the coolant temperature reached 98°C. The new fan is behaving exactly the same way. However, the difference is that there’s no “roar” at startup which used to there before i started playing around with vehicle. It only locks up at 98°C and immediately slows down when the temperature drops to 95°C. The needle goes slightly up the normal notch (2nd notch) when temps are at 98C.

I also replaced the thermostat with a low-temperature one, and now, on the highway, the coolant temperature stays between 78-84°C. According to my tuner, there is no available tuning parameter for the fan speed in this model, although the platinum-spec (400hp) version does have that option. I even returned the ECU to stock, but there was no difference.
There is no overheating despite alot of dune driving in low gear.

Now, I’m considering installing two electric fans in front of the condenser that I can turn on manually when needed. i would prefer the simple mechanical fan over this contraption from Nissan.

Honestly, i think it is functioning perfectly. The temperature parameters you are quoting sound exactly correct. the temp gauge is perfect and the fan coming on and off at those temps is exactly what id want my fan to do.Perfect.

I have just re-read the thread. I think PeeBee hit is pretty right mate. Although the fan should not be needed at idle on a 20c day it is not the end of the world especially on a tuned engine. I would re-fit the old fan and give it another go. do the idle test and see if the fan comes on. Note the Temp gauge will have a massive dead spot in the middle where it wont move between standard running temp and the temp set from factory of the Thermostat opening. It is considered normal range so Nissan leave it to Not Move withing this range.
12th April 2025, 02:19 AM
hsbashraf

Quote:

Originally Posted by MudRunnerTD

Honestly, i think it is functioning perfectly. The temperature parameters you are quoting sound exactly correct. the temp gauge is perfect and the fan coming on and off at those temps is exactly what id want my fan to do.Perfect.

I have just re-read the thread. I think PeeBee hit is pretty right mate. Although the fan should not be needed at idle on a 20c day it is not the end of the world especially on a tuned engine. I would re-fit the old fan and give it another go. do the idle test and see if the fan comes on. Note the Temp gauge will have a massive dead spot in the middle where it wont move between standard running temp and the temp set from factory of the Thermostat opening. It is considered normal range so Nissan leave it to Not Move withing this range.

Thanks for the response. I think you are right. I have changed the fan relay and fuse and i think it improved the response of the fan. But you are right this is normal operation of y62 fan. I was out today in desert with ambient temps at 40C alot of 1st,2nd gear driving and no over heating. The temps never went above 98C. I am still planning to add 2 electric fan infront of the AC condenser to manually turn on while in Desert. Thank you all.