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Rb25det Running Hot - Help Please

jessr33

By jessr33,
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jessr33

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Posted

Hi Guys,

I have done a lot of research and I still feel that I need a lot of assistance on this please so I am ever so sorry if this has been posted somewhere and I have missed it.

I have a R33 GTS-T with a HKS GT2535 and plenty of upgrades running at approximately 235rwkw (safe tune).

Back when it was a bit cooler a few weeks ago my average water temp was 85 - 90degrees and now that the temperatures are in the 30's + it is now running at 95 degrees on average and has gotten up to 102 which is the highest I've seen it. I'm getting this temperature from my Power FC hand controller. My stock temperature gauge has never budged above 'average'. On the weekend I did a radiator flush and put in the best coolant on the market hoping that this would assist in cooling it down a bit thinking maybe the previous owner had diluted the concentrated mix a bit too much however this didn't assist.

I have read that the coolant is safe up to approximately 137 degrees and my oil (10W - 40) is safe up to 148 degrees and with the oil temp being an average of 35 degrees hotter then the water temp my car should be pretty safe still at the moment on the basis that it does not get any hotter!

I do not have an upgraded radiator and I am aware that the front mount intercooler does reduce air to the radiator causing these cars to be hotter then normal. I would prefer not to upgrade the radiator if there is another way around cooling my car down quite substantially. I haven't replaced the thermostat yet but it is on my to do list this weekend as well as taking my radiator to be properly serviced in case it is seriously blocked.

I have read that an Oil Cooler will divert the oil through the cooler once the oil reaches a certain temp and will cool the oil and the whole car? If this is the case then would I need to upgrade the radiator?

I do not know much about Oil Coolers and wouldn't have a clue where to start to be honest. I have read about them but nothing has pointed me in the right direction. What is better, getting an Oil Cooler that only diverts the oil once at a certain temp or one that is flowing the oil through all the time? Does anyone recommend any particular brand or 'type'? What real difference does it make as to whether I buy a 19 row, 25 row or a 50 row? Will it cool my car a lot more to get a 50 row or is it really about the amount of space I have in the engine bay?

I apologise for all the questions and would really appreciate no one bagging me out for 'not knowing enough' or doing enough 'research' as I really have tried my absolute hardest and I don't particularly want to get ripped off by some mechanic trying to bollocks me with unnecessary expenses. (the negative attitude is from people giving me crap before for asking questions! :wave:

Any assistance on this matter is GREATLY appreciated! :laugh:

Cheers Guys!

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jeffworld2 Veteran

jeffworld2

Posted
Posted

check again to see how much coolant you have, it may have gone down a bit after running a while to get air out. just happens.

if you have fresh oil, then a simple check would involve removing the thermostat all together. unbolt the housing and remove it with a flathead screwdriver, then remove the thermostat and put everything back with some new liquid gasket. if it overheats without a thermostat, then there is something pretty wrong with your cooling system.

GeeTR Grand Master

GeeTR

Posted
Posted
Hi Guys,

I have done a lot of research and I still feel that I need a lot of assistance on this please so I am ever so sorry if this has been posted somewhere and I have missed it.

I have a R33 GTS-T with a HKS GT2535 and plenty of upgrades running at approximately 235rwkw (safe tune).

Back when it was a bit cooler a few weeks ago my average water temp was 85 - 90degrees and now that the temperatures are in the 30's + it is now running at 95 degrees on average and has gotten up to 102 which is the highest I've seen it. I'm getting this temperature from my Power FC hand controller. My stock temperature gauge has never budged above 'average'.

The stocker gauge is more like a 3 way switch, not a constant smooth response, as you've seen; its moved 20 degrees on the HC, and shows nothing on the stock temp gauge. Its to stop the average commuter from freaking out.

On the weekend I did a radiator flush and put in the best coolant on the market hoping that this would assist in cooling it down a bit thinking maybe the previous owner had diluted the concentrated mix a bit too much however this didn't assist

Did you take it somewhere to flush, or do a "home treatment"?

I do not have an upgraded radiator and I am aware that the front mount intercooler does reduce air to the radiator causing these cars to be hotter then normal. I would prefer not to upgrade the radiator if there is another way around cooling my car down quite substantially. I haven't replaced the thermostat yet but it is on my to do list this weekend as well as taking my radiator to be properly serviced in case it is seriously blocked.

Stock radiator and an aftermarket IC still shouldn't really make your car that much hotter. Pull the thermostat out and test it. Procedure should be in the workshop manual; place in water on stove with a thermometer and make sure it opens at the right temp

I have read that an Oil Cooler will divert the oil through the cooler once the oil reaches a certain temp and will cool the oil and the whole car? If this is the case then would I need to upgrade the radiator?

I do not know much about Oil Coolers and wouldn't have a clue where to start to be honest. I have read about them but nothing has pointed me in the right direction. What is better, getting an Oil Cooler that only diverts the oil once at a certain temp or one that is flowing the oil through all the time? Does anyone recommend any particular brand or 'type'?

An oil cooler is an oil cooler, it doesn't redirect anything. Your thinking bout a oil thermostat, or Oil Stat... but most people in Oz don't need / use em.

I apologise for all the questions and would really appreciate no one bagging me out for 'not knowing enough' or doing enough 'research' as I really have tried my absolute hardest and I don't particularly want to get ripped off by some mechanic trying to bollocks me with unnecessary expenses. (the negative attitude is from people giving me crap before for asking questions! :wave:

Any assistance on this matter is GREATLY appreciated! :)

Cheers Guys!

"Use the search button noob"

..

...

Haha, just joshin man, you've clearly done your looking and are desperate to get the issue fixed.

Good luck, let us know how you go

RANDY Veteran

RANDY

Posted
Posted

Well... if an auto skyline is like an auto Commodore, the radiator cools the oil also.

In which case, an oil cooler could very well help depending whether you hook it up to the in or out side of the radiator. Ignore this if you're a manual though, hey?

I would guess also, that if the oil is cooler, the water won't get as hot trying to cool the block? So it might be valid anyway?

I guess your last few things to try would be to have a mechanic inspect your waterpump, and check the flow of the radiator.

You might be able to self-test the radiator flow... if you touch (quickly) the upper and lower radiator hoses, and they're the same temp (hot), then it's probably fair to say that the coolant is making it through the whole system, and that the waterpump is doing its job. (and that the thermostat *is* actually opening)

If one side is much much cooler to the touch, then it could be one of those three things: stuck thermostat, faulty waterpump, or a blockage in the core of the radiator.

Well.. it's a free test, might be worth a quick check? (Check after some normal driving, and the temps are up to what you don't like. Then engine off, if you're sticking your arm down the inside of the radiator!)

jessr33 Collaborator

jessr33

Posted
  • Author
Posted

Thanks so much for your assistance Guys!

I did the flush at home last weekend, I enjoy doing these things myself :P

I am going to take the Thermostat out this weekend and see whats going on and from there if there are no improvements I'll try some of the other suggestions.

I'll keep this up to date with where it all takes me, hopefully it won't be too complicated or expensive to fix not that it really matters cos after all it is my life, my pride and joy :laughing-smiley-014:

Cheers once again! :)

GeeTR Grand Master

GeeTR

Posted
Posted
Thanks so much for your assistance Guys!

I did the flush at home last weekend, I enjoy doing these things myself :)

Np.

Keep in mind, the home flush treatments are nothing compared to a proper tank dunk by a radiator specialist.

jessr33 Collaborator

jessr33

Posted
  • Author
Posted

Okay, here's the go, Lazy Jess didn't take out the Thermostat on the weekend.... BUT I've noticed something that might assist in pointing out what the problem is!

As you all know my car gets HOT, first thing is, if I'm driving at 100kms constant it will sit at around 97-99 degrees but when I'm driving at 70-80kms an hour it cools down to 93-95.

Now the biggest thing I've noticed is, when my car gets above 97 degrees I now turn my heater on, I put it on 32degrees full blast and within 5 minutes my car always cools down to 90degrees or sometimes lower and just stays there, does this say anything in particular?????

Any thoughts are appreciated, I think my overall answer is to just upgrade the damn radiator, I'm not intentionally being lazy, just have a lot going on :ph34r: and I guess I am big time procrastinating too but hey if the heater is cooling my car down when it gets really hot then its not too much of a huge problem right this second as such (just trying to excuse my laziness! :rofl: )

Thanks Guys!

  • 5 months later...
bumble_bee Rising Star

bumble_bee

Posted
Posted
Now the biggest thing I've noticed is, when my car gets above 97 degrees I now turn my heater on, I put it on 32degrees full blast and within 5 minutes my car always cools down to 90degrees or sometimes lower and just stays there, does this say anything in particular?????

yeah, cars do that..wen using the heater that is fully cranked up..full fan speed..and the highest temp..

that the engine does cool quicker...

its good if u just bein doing drags or bein doin burnouts for a while..o do this if u want ur engine to cool down quicker....

i dont have a rough idea why..but maybe??

wen the temp. switch or climate control to the hottest temp. eg. 32degree's....

the blower motor is using engine heat..

which is being suck in through the cowl cover(air vents)???

which causes ur engine heat to sucked away..is this correct??lol

just a theory..lol

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