Water temp issue

[-S-]

Hi all. Need some feedback with my heating issue.

 

Few days ago, i finally get to drive my car after about 14 weeks. So i noticed temp was ok during spirited drives. Temp slowly climbed up during stop and go traffic. I stopped by a shop to get me a bottle of water to top up radiator. I knew its going to be a long wait before I could open the radiator so decided to tow it back home.

 

So next day decided to top up radiator and to my surprised its full. (Using a trust radiator btw)

 

So now I'm not using a thermostat (mechanic saw thermo was a bit worn) and have replaced the clutch fan with a used one. .. and still temperature is rising ONLY when not driving.

 

I'm hoping my problem is due to the clutch fan hub? Have ordered nismo thermostat for now. I thought I'll ask around for feedback/experiences. Thanks!

[Duncan]

well yes, normally when it only gets hot when moving slowly or idling you would suspect fan; but clutch fans are pretty reliable and are always going to turn somewhat when the engine does (unlike thermo fans which can be not running at all due to wiring, fuse, relay etc). It could be the fan's clutch but normally they fail the other way (ie always on, making it very noisey even at idle)

In this case it may simply be a blocked radiator or similar where the lack of airflow through the radiator is showing up the issue

[89CAL]

I have had a fan clutch start to fail the other way. Car got hot when stopped. So it can happen

Is your shroud O.K? Is there any gaps where air could recirculate around the radiator?
If the car is hot and you rev it, can you hear the fan really working?
Also, less likely, is your radiator cap sealing correctly?

As above, I would pull the radiator out, give it a good clean and straighten any bent fins then re-install. Put new coolant in and bleed properly

If this is a street car, I would strongly suggest you by a standard thermostat rather than a Nismo one

[-S-]

Anyone knows the part number for oem thermostat?

Also... is a radiator easily blocked? I've only used it for less than 30k mileage. And thing is i didn't use coolant back then -_- but since this issue, the mechanic has flushed it 3 times after every trouble shooting. Water is getting cleaner though. .. planning to flush it another 2 times or so before putting in coolant. ..

[89CAL]

Perhaps you should have mentioned that........

Look up kudos motorsport. They will sell genuine ones and have the part number with the part.

Also..... by 30k do you mean 30km or 30,000km?

I would still go over all i have suggested and more. Doesnt take too long. Definetly put some good coolant in when done flushing though

[-S-]

30,000 km... so i would have thought that its still clean just the usual rust inside. ..

[-S-]

Btw... since in not using a thermostat at the moment. .. assuming the fan clutch is working fine. .. will the water temp reading be at the usual "okay" reading? I'm curious with this one. ..

Just got back from a high way cruise doing hard pulls now and then and can confirm temp did went down. I also notice if i turn on the air conditioner the temp will rise a little faster when driving slowly...

Safe to say my issue is the fan hub?

[89CAL]

No... Your issue is air flow

It is quite likely it is the fan hub, but it is important not to just focus on that. I would still pull the radiator out, seen as it only has water in it. Get a pressure washer and clean through the fins. It is unlikely this is the issue but important to make sure air can get through the radiator easily

Do you have the fan shroud installed? Can you post a photo of the fan/radiator/shroud if possible? Might be something simply you are missing (happens to all of us)

If you are going to get a new fan hub either go genuine Nissan or Dayco. Both seem to work fine

[-S-]

[-S-]

Got bad news. Apparently idiot seller suddenly told me my nismo stat is ready to be shipped so can't cancel it. Is it really bad for a street driven car? Its not my daily but when i drive it , i usually drive it hard... who doesn't?

[Duncan]

Well, it won't make it explode into a ball of flame or anything. But the car will run colder than it is meant to which means the ECU will make it run richer = more fuel use and to a lesser extent more fuel contamination of oil. The standard thermostat is fine for street cars.

Running a colder (or no) thermostat is really just a bandaid for a cooling system with some other problem....in any case once the thermostat is fully open the temp is determined by whether the cooling system can remove the same or more heat as the engine is putting in.

[-S-]

I take it that applies to all ecu ?

[Duncan]

Generically, yes, any ECU will add more fuel when the car is cold than when it is warm. If you have a tunable ECU you could take fuel out at about 62 because that will be "warm" for your engine. Standard thermostat and tune will expect 76o

[blind_elk]

Any chance that the impeller on the water pump is failing?

Does the car still have the undertray fitted?

[iruvyouskyrine]

I may buy the Nismo Thermostat. PM me.

[-S-]

Any chance that the impeller on the water pump is failing?
Does the car still have the undertray fitted?

Yeah we did remove and check water pump too. Still looks good.

[-S-]

I may buy the Nismo Thermostat. PM me.

I might use it since i have a Tunable ecu...

[-S-]

Generically, yes, any ECU will add more fuel when the car is cold than when it is warm. If you have a tunable ECU you could take fuel out at about 62 because that will be "warm" for your engine. Standard thermostat and tune will expect 76o

Do i need to be precise with the figures ? Or just roughly? I am using an ancient ecu though if that helps... kinda regret getting this nismo. Bloody hell why did i not do my research before buying. ..

[89CAL]

Thermostats are not that expensive.......
Sell Nismo one

[-S-]

Fixed. Fan hub was the culprit. Btw i might not have noticed but Running without thermostat i was getting 65 degrees during cruise! Now using a standard oem thermostat averaging at 82 degrees . Shouldn't it be at 76 ish? never take notice on water temp til i had this issue lol.