Water Temp Go Up To 98 When Drive In Heavy Traffic?

[bubba]

Due to the coolant properties the boiling point is about 110deg.

The stock gauge in my 32 doesn't move significantly from halfway till about 100deg.

Edited July 20, 2009 by bubba

[mad082]

first thing i would be doing is checking the thermostat. had a similar problem in a car of mine (not a skyline) quite a few years ago. radiator and clutch fan were working fine but the thermostat was stuffed. put a new themostat in it and it fixed it straight away.

not saying this is definately the answer, but i would try it first. it is something you can do easily yourself and doesn't cost much, and if it doesn't work you at least know that it is one less thing to worry about.

other possibilities are:

-partially blocked radiator

-fan not working properly (has been discussed)

-water pump not working properly/worn (pretty sure my 33 had this but it was running hot at all speeds. also had this problem with my outboard motor. impellor wasn't making a tight seal and was pretty much pumping no water at low rpm and getting really hot but was pumping a bit at high rpm but was still running hotter than it should)

[GTRNUR]

i found when the water temp go up to 98 on center gauge, the water temp only about 90 on pfc.

Yes your right, the MFD reads from the single wire temp sensor on the thermostat housings output to the radiator, and the PFC sensor reads from the temp of the water that is actually being circulated. Basicly the temp sensors are reading from diferent coolant streams.

If your aircon is on i'd be saying 90 degrees stuck in traffic is pretty normal, though getting towards the high end of hot. Hottest ive seen was about 88 on the MFD when driving in mid NSW in the middle of summer with over 40 degrees outside air temps at around 110km/h or so.

Just because you have an R34 seems everyone always offers up the things to check that are so dam expensive first. There are a lot of cheaper things to check first.

1. With the car cold, start the car and top up the radiator with distilled water, and open the air bleed on the drivers side top/front of the head to bleed out all the air. If there was air then thats probably part of the problem.

2. Check the overflow bottle has coolant.

3. Check the condition of the hose from the radiator to the overflow bottle. If its able to suck air, it will and that is filling the cooling system with air when the engine cools down, gradually making it worse.

4. Foam rubber. The radiator should be sealed to the shroud and the front of the car with a foam rubber seal, all the way round. If this is falling apart or missing all together get it fixed. It stops/reduces the fan re-circulating hot air when you are stationary.

5. Clutch fan... starts to get expensive but 2nd hand ones can be had for $50.

It definatly wont be the thermostat, pump or the radiator, as its not overheating when on the highway. The facts are the engine generates WAY more heat at highway speeds than it does when idling in traffic. And highway temps are under control. Clearly the thermostat, pump and radiator are working properly.

Cheers,

Ian

Edited July 21, 2009 by GTRNUR

[ricknismo]

Interesting read, I have had 4 GTR's now..32,33 and 2 34's and I live in central qld and I can say that all of them have reached 100.

Water under pressure I believe boils at about 110 but 100 was the point I'd change my driving or turn off ac etc.

[bubba]

get the radiator professionally cleaned and a new top tank. should be 230-300

they take it out, take it apart, clean out all the crap etc. good as new. a new OEM or nismo thermostat is a good idea at the same time. The generic ones are very flimsy in comparision. nissan is ~50$ trade price. 82deg where the nismo is 72deg

Most of the RB's run a 72.5deg thermostat, Neos run 82deg (it was done for emissions reasons and 34gtr is the same era so it might too), Nismo thermostats are 62deg but unless you have a track car with custom management, they aren't that good an idea.. e.g. VCT on my Neo engine doesn't operate until the engine is over 70deg

Normal operating temp for all the RB's I've had seems to be about 80deg, except the Neo which likes to sit at 85deg. I would be slightly concerned if temps were nearing 100 and would be looking at the routine cooling system maintenance referred to by others above. Personally I've seen 105deg in the 32 after a thorough torching of the tyres on a 40deg day.. didn't even throw any coolant out

Edited July 27, 2010 by bubba

[Kinks]

98deg water temp is ok, it is a little high (check basics) but it wont kill the engine etc

just drive it normally once you are able to and the radiator has some airflow

once you drive it normally with airlfow, the temp should drop pretty reasonably to mid 80s

the ECU has correction based on water temp and will start taking out timing above certain levels

if water temp is near 110deg i would be worried - the stock guage cluster should be near 3/4 at this level

yep - i had a blocked radiator and didn't know about it until a spirited drive had the needle climbing. after that i checked with a consult cable and I was sitting at 94C in normal driving, sitting still it got up to 104C and the needle was still at the halfway point that is much too hot for my baby!! poor thing must be about to pop an o-ring by the time the needle even starts to move. that said they are bloody strong motors.

new radiator = steady 85C which is what the thermo opens at from memory.

also, if your radiator is blocked the clutch fan will not engage because the clutch senses air temperature from the radiator's hot side. blocked rad = cool air = no clutch fan. mine started working again as soon as i changed the radiator.

[KiwiRS4T]

9 times out of ten if your car is overheating its a blocked radiator. Its almost worth doing any way take the radiator (or the car if you prefer) to a radiator shop and get them to open it up and clean it out (flushing won't do it) and if they recommend a new core get one - its worth it.

[Titan457]

How big is your front mount, might be time for a rad upgrade, we ran a huge trust kit in ours and with a PWR rad, and SPAL thermo fans, fixed the problem, no more worries.

[bubba]

new radiator = steady 85C which is what the thermo opens at from memory.

No it doesn't.. RB25Neo is the highest Nissan thermostat I have seen at 82deg. RB20/25/26/30 should be 72.5deg.

[ricknismo]

A strange thing. My altenator earth was a bit dodgy.

I fixed at all my temps dropped a bit

[NewKleer]

Interesting read, I have had 4 GTR's now..32,33 and 2 34's and I live in central qld and I can say that all of them have reached 100.

Water under pressure I believe boils at about 110 but 100 was the point I'd change my driving or turn off ac etc.

higher than 110, maybe 115 or so. or maybe 125 or so if it actually has 'coolant' like it should and not 100% water.

people think 100 is dangerous cause they know normal water under atmospheric pressure boils at this. but things change a lot with pressure and when you use coolant.

the fan in my pulsar doesnt come on till 95C, thats how 'normal' those kind of temps are.

i wouldnt be worried if you're hitting 100C, id only be worried if you're hitting temps you never have before, as that could indicate something has changed/is malfunctioning etc.