r34 RB25NEO ALWAYS Overheating - HELP

[Dil-Dog]

Hello Everyone, 

I have:
New Mishimoto Radiator
New Mishimoto Electric and Shroud (came with ONE fan)... wired professionally from a ignition source from the Fuse Box and wired with its own fuse and relay. 
New Mishimoto Colder range Thermostat

and YET! it still overheats in 10 mins on the street with regular driving either and day 29 degrees C or Night 27 degrees C

The Dash Board's Temperature gauge will slowly climb to about 75% to the top and then at a certain point will start slowing jumping up and down and up and down from 75% to 95% (overheating).

I was told that: 
-The single electric fan is ass and cant cool the radiator so go back to the clutch fan and shroud.
-The Thermostat is faulty/not working. replace it and one guy even said dont even use one. I live in the Caribbean by the way... 
-When switching over to a GReddy Forward Facing Plenum, the coolant temp sensor could have been damaged/stop working. But the engine bay is HOT!

 

[KiwiRS4T]

First of all why did you change the radiator? If it was ok before then revert to the stock set up and sell the Mishimoto.

While you have it apart remove the thermostat and back flush the block.

Fit a stock thermostat. Then test the new one to see if it was faulty. Even if it is not, a low temp thermostat just opens earlier. Once open it has no effect what so ever on the running temps of the engine.

[Dil-Dog]

  On 07/11/2019 at 7:52 PM, KiwiRS4T said:

First of all why did you change the radiator? If it was ok before then revert to the stock set up and sell the Mishimoto.

While you have it apart remove the thermostat and back flush the block.

Fit a stock thermostat. Then test the new one to see if it was faulty. Even if it is not, a low temp thermostat just opens earlier. Once open it has no effect what so ever on the running temps of the engine.

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Well i was obviously looking for better cooling capabilities out of this upgraded set up.... I have a feeling it may be the Thermostat possibly not opening? i am not to sure, how could you find out if a thermostat is doing its job?

[TerryP]

Several things can contribute to this, however since you have recently replaced the radiator:

1. Ensure ALL the air has been bled out of the coolant system, there is a 10mm hex head bolt near the front of the plenum for this purpose.
2. You did not mention if the water pump was replaced, as per the manual this should be done every 100,000 km at the same time as the CAM belt.
3. If you have access to diagnostic software and equipment for this car check the O2 sensor, if this is faulty your engine may run lean to 'compensate' for a bad reading, the leaner the fuel mix the hotter it will get.

[TerryP]

  On 07/11/2019 at 8:51 PM, Dil-Dog said:

Well i was obviously looking for better cooling capabilities out of this upgraded set up.... I have a feeling it may be the Thermostat possibly not opening? i am not to sure, how could you find out if a thermostat is doing its job?

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To test a thermostat, remove it from the vehicle clean it, put it in a pot of cold water with a temperature gauge and slowly heat it on a stove. It should reach its maximum valve travel at the temperature it is rated for and stop moving, if it does not stop moving or does not fully open it needs to be replaced.

To find out the specs look up the part number of the manufacturers website, there should be a datasheet indicating it's travel values

[Kinkstaah]

It is also worth noting that generally speaking, the cooling system for R chassis is actually pretty decent. Even if you're doing 30 min track abuse sessions the stock fan/shroud does the job, let alone street driving. I know it's already been suggested but getting back to a known good setup is recommended.

To be fair a decent thermo setup shouldn't cause issues for street driving either.. but its safe to say the stock Nissan Fan/Shroud/Radiator/Simple Rad upgrade that bolts to OEM positions/gear won't.

[GTSBoy]

Didn't bleed the cooling system properly. No need to consider any other option.

[Dose Pipe Sutututu]

Mishimoto fans are junk, throw it into the bin.

Use the stock 250kW (or whatever your motor is making) fan you have, if you don't have it go buy a SPAL electric fan to replace that Mishimoto junk.

[wildeagle44]

+1 mishimoto fans are no good. Been there done that. 

Also check with an aftermarket gauge or plug into the ecu to verify your temps

[georgev]

I experienced the same problem with Mishimoto rad and fan on my R33.  I put a stock fan back on and the problem was solved.  The factory fan blows a lot more than the little Mishimoto fan.  Both rad and fan are a downgrade. 

[Dil-Dog]

UPDATE: 

For those who care and for anyone who may be able to learn and get help from this post for their projects... the problem the god awful mishimoto electric fan.
 

Its sucks booty butt cheeks and is better off being a fan for a computer or somthing... the stock clutch fan is honestly 10 times better in terms of air flow.

[GTSBoy]

Yes. But shit fan or not, it still shouldn't overheat while just driving around. Low power + moving car should be enough air through the radiator.

Also shit radiator.

[Dose Pipe Sutututu]

  On 11/11/2019 at 10:44 PM, GTSBoy said:

Yes. But shit fan or not, it still shouldn't overheat while just driving around. Low power + moving car should be enough air through the radiator.

Also shit radiator.

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Not in city traffic though, especially with a FMIC in front.

And like I said earlier Mishimoto fans are junk, also have said it in the past too but people get butt hurt and get all defensive lol

[TerryP]

Never had any trouble with the standard viscous clutch fan myself, wouldn't even consider swapping it unless it broke and I couldn't find a replacement....

[BoZZa17]

Mishimoto? sounds like some Mitsubishi after market brand....  aint none of that going on my Nissan.

+1 for stocko clutch fan.

 

only reason to change a clutch fan is if ur cold startin an e-series falcon and setting off in the morning.

(falcon sounds like ur doing 300km/hr......people look out their windows.... and see u...……... doing 3)

[niZmO_Man]

Yeah my R32 sounds like that, makes people move out of the way lol

[kowalatea]

As I've read so far most all would rather stay with the factory clutch fan....... buuuut if one was going to take the time to wire in a set of electric fans. Which ones should be avoided or not even considered( like said mishimoto)

[KiwiRS4T]

  On 25/02/2020 at 5:21 AM, kowalatea said:

As I've read so far most all would rather stay with the factory clutch fan....... buuuut if one was going to take the time to wire in a set of electric fans. Which ones should be avoided or not even considered( like said mishimoto)

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All of them.