Jump to content
SAU Community

Recommended Posts

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!

Link to comment
https://www.sau.com.au/forums/topic/469629-water-temp-issue/
Share on other sites

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

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

  • Like 1

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. ..

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

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?

  • Like 1

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

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.

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

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. ..

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.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Harness is for a s1 Rb25det, and it is engine and lower harness.  the old harness had broken off plugs and was in very rough condition/exposed wires and splices etc. it is not able to be put back on the car, I could visually inspect to see if they had rewired any pins on the ecu plug. The fuel pump definitly isn’t turning off it’s an external pump and very loud you can hear it. Will look at the other harness tonight, am also going to pull the fuel rail and watch the injectors spray, will update here with what I find. Pretty sure at this point it has to be something to do with injectors because car will fire up on starting fluid and cas is clicking the Injectors. Fuel pressure is steady 43psi 
    • Check the injectors flow evenly, and are actually flowing what you and the ECU think they should be flowing. If it's starting up on starter fluid, you have a fuel issue. Is it possible under cranking your fuel pump is turning off?   The harness you replaced, is that the whole engine harness? Do yourself a test, and drop the old harness on and plug it into the Z32 ECU. It's possible they've wired things different. From memory S1 to S2 is different in RB25 and you may have a wrong loom
    • I haven’t pulled the injectors to watch them spray yet but they are clicking from the cas and all of the spark plugs are wet with fuel. I’ve thought the cylinders were being flooded from the beginning and was hoping fuel pressure would fix it. Tonight I am going to pull the rail and watch the injectors spray. Don’t know how to test/diagnose if the plugs are firing in correct sequence but that should be a timing thing and as far as timing goes my car still has the half moon for the cas can only install it 1 way. And my mechanical timing is 100% correct I posted photos above. Confirmed with the balancer on and off. 
    • I checked spark on all cylinders and they all visually have spark with the plug pulled and grounded, but plug 1 is the only one that fouled. This was a running swap that blew up and was rebuilt by a machine shop, put a new wiring specialties harness and did all gaskets, studs, and bolts while it was out.  compression is 135-150 across all cylinders. Aside from that from my understanding with the z32 ecu and maf the car should start regardless. The wiring for TPS and the dual 02 sensor/ dual knock sensor stuff shouldn’t actually stop the car from starting or even running well, (just slightly rich)  they just give fault codes. Car supposedly is supposed to start as long as you have z32 afm and ecu with the nistune base map and that’s info coming from a well known and trusted tuner who does a lot with SR/RB (Rsenthalpy). After more trouble shooting today where I’m at right now is that the cas is sending signal to the injectors they click while spinning the rotor, Fuel pressure is now set at 43psi, all cylinders have good compression and all of the plugs looked great (just wet with fuel) except for cylinder 1 which was very black (cylinder 1 has 150psi compression). all of the coils generate spark if pulled out and grounded out on the head. On the fuel pump car just pops into the exhaust. On starting fluid car will fire off. Hard to tell if all cylinders are firing off but definitley a couple. sounds like all of them but it’s only for 3-5 seconds hard to tell. 
×
×
  • Create New...