R33 Oil & coolant temp high on idle

[noperope]

The car has been running fine during everything from cruising to drift events while on the last drift event the temperatures started to run off after just 2-3 laps. The oil reached about 105C after which I took some cooling laps and got the temperature rather quickly back to 85-90C, the coolant was also increasing steadily and occasionally reached 100C while sitting on the grid, requiring some longer cooling runs. The weather at the time was about 25C.

Since that day I have had the temperatures creep up as as soon as the car is standing still will continue to increase, to the 100C and above. While cruising on the highway at 130km/h and 20C (cloudy) weather the oil sits at about 85C and the coolant about the same, but as soon as I stop the temperature starts rising again and within 5-8 minutes the oil temp reaches 100. The symtoms are the same from cold start, the temperature will continue to increase until there is air flowing through the radiator. The fan is running, not oil leaks or coolant leaks, the oil level is on par and the oil pressure is about 2bar on idle and 5 bar on 4k rpm. I'm using Greddy after market gauges. 

I'm running a RB25 with about 500hp, forged pistons, metal head gasket, GTX3076, after market radiator, oil cooler (mounted in front of the radiator).

I have tried to searching for similar threads/articles but usually find that their overheating problems are regardless of moving or not. 

Any ideas on where to start? 

Edited June 27, 2020 by noperope

[WR33KD]

I run a similar setup in my rad and oil cooler. At idle it won’t go passed 86 and after 7 hard laps I’m lucky to see 95 and after a good 45sec burnout it will hit 105 bit drop down real quick. Those are all water temps unsure what my oil gets to.

Guessing you have an aftermarket ecu? Can you log in to it and see what your fans and set to come on at?

[noperope]

5 minutes ago, WR33KD said:

I run a similar setup in my rad and oil cooler. At idle it won’t go passed 86 and after 7 hard laps I’m lucky to see 95 and after a good 45sec burnout it will hit 105 bit drop down real quick. Those are all water temps unsure what my oil gets to.

Guessing you have an aftermarket ecu? Can you log in to it and see what your fans and set to come on at?

That's what I used to see as well even during drifting. I'm running a Link G4 so I should be able to have a look what the settings are, however, I just want to point out that nothing has changed since it went on the dyno earlier this year. I'll take this into advice and see if I can maybe export some log-data while I'm at it.

[hardsteppa]

Have you tried a new thermostat?

[hotz]

Check your thermostat mate. Best wishes.

[GTSBoy]

So, it is one of a very few things. Thermostat, as advised above. Radiator compromised. Water pump vanes eroded away.

Go forth and apply the logical procedure to work out what is wrong.

[KiwiRS4T]

Are you using the stock fan? What kind of radiator do you have? Does the radiator shroud fit properly with your new radiator?

[noperope]

9 hours ago, GTSBoy said:

So, it is one of a very few things. Thermostat, as advised above. Radiator compromised. Water pump vanes eroded away.

Go forth and apply the logical procedure to work out what is wrong.

The engine was pulled apart at the beginning of last year and had the water pump changed at the same time.

 

8 hours ago, KiwiRS4T said:

Are you using the stock fan? What kind of radiator do you have? Does the radiator shroud fit properly with your new radiator?

It's the stock fan indeed but the shroud is gone since a long time, never had it.

 

11 hours ago, hardsteppa said:

Have you tried a new thermostat?

As many of you already pointed out, I will have at the thermostat and replacing it regardless since it's such a cheap part and I don't know if it has ever been replaced. I'll report back when it's done.

[Ben C34]

Kiwi nailed it. It's the lack of shroud

[GTSBoy]

20 hours ago, Ben C34 said:

Kiwi nailed it. It's the lack of shroud

 

20 hours ago, noperope said:

the shroud is gone since a long time, never had it.

 

I would have agreed with Ben, except that the change is recent and it has apparently never had the shroud. If it was the missing shroud, you would expect the problem to have always been there. That would suggest that it is something else that has changed recently. So, back to my earlier list, starting with the others' thermostat recco.

[noperope]

Having flushed out the coolant and replaced the thermostat it would appear as that has done it. The temperatures are holding steady around 80C. Never done this work before so it's been a learning experience. I'm going to test the old thermostat to see if it's completely or maybe just partially shot.

Anyho, thanks for the replies guys!

[tridentt150v]

You could have had air in the system as well?  An incomplete bleed when the radiator was last done could do that.