Jump to content
SAU Community

Recommended Posts

Hi,

My car has recently begun to overheat.

Initially the first instance presented as very high oil temperature reaching 110 degrees.

a couple of minutes later, after passing 110 mark I noticed the water temperature begin to rise above half way.

Once I reached home I noticed the overflow full of coolant. Mind you it was old coolant.

So after changing the thermostat, coolant, and radiator cap I tested its stability under load.

and sure enough the oil temperature does still reach 110 eventually.

Originally I thought this might just be due to thrashing around abit.

So I decided to go for a run on the freeway. 100 kmh for 30 minutes.

Sure enough the temperature reach 110 again, but water steady.

My questions are, and I apologise for my ignorance.

1) Is the oil heating the water? or is the water heating the oil?

2) if the oil is heating the water, why is it reaching such a high temperature?

3) if the water is heating the oil, what could be causing this?

Thanks

Link to comment
https://www.sau.com.au/forums/topic/461511-high-oil-temp-r34-gtt/
Share on other sites

Hi, My car has recently begun to overheat. Initially the first instance presented as very high oil temperature reaching 110 degrees. a couple of minutes later, after passing 110 mark I noticed the water temperature begin to rise above half way. Once I reached home I noticed the overflow full of coolant. Mind you it was old coolant. So after changing the thermostat, coolant, and radiator cap I tested its stability under load. and sure enough the oil temperature does still reach 110 eventually. Originally I thought this might just be due to thrashing around abit. So I decided to go for a run on the freeway. 100 kmh for 30 minutes. Sure enough the temperature reach 110 again, but water steady. My questions are, and I apologise for my ignorance. 1) Is the oil heating the water? or is the water heating the oil? 2) if the oil is heating the water, why is it reaching such a high temperature? 3) if the water is heating the oil, what could be causing this? Thanks

there's a factory heat exchanger which keeps the water and oil temp inline.. benefits of this.. cools down the oil when it gets too hot and also brings oil temperature to operating temps

Draw backs, if the oil temp exceeds the water temp, it will bring the water temp up. A way around this is to increase your cooling capacity by installing a decent radiator which should theoretically keep the water temps in check and also keep the oil temps a little lower.. but real world says you need to also install an oil cooler to bring the overall temperature of both oil and water down.

People often look for highly technical reasons for overheating..

My first thought always is to take the radiator (or the whole car if you are so inclined) to a radiator repair shop. They will take the top tank off and clean out the core, replace the top tank if necessary (many are plastic) and tell you if a recore is indicated. They can flush the block and replace the thermostat.

If you haven't done this in recent history it is worth doing anyway and will very often fix your problem.

The oil heat exchanger serves 2 purposes.

Firstly it helps get the oil up to temp quicker by pulling heat of of the water and transferring it into the oil and secondly it works the other way around by transfering heat from the oil back into the water once the oils too hot.

Ideally the oil and water temps should be at the same temp as the factory thermostat.

Now if your water temp is good but your oil is getting too hot, there's something wrong if your just cruzing.

Start by checking the oil temp sender and wiring (and possibly gauge).

A bad connection may be causing too much resistance which may explain the high temp readings.

  • Like 1

Due to the water/oil heat exchanger I'd say you are just seeing your water temp reflected on the oil temp gauge.

On my R33 with a blocked radiator the factory water temperature gauge sat at half way from 70C all the way up to 105C - it never budged. Only when you head up north towards 110C the water temp gauge starts to show it getting "a bit warm" - IMO 105C is already way too warm!! (was checking actual WT values using Consult tool).

Blocked radiator, blocked/faulty thermostat, or bad water pump.

As a point of reference my R34 GTT handled continuous abuse on the track and the highest I think I saw was 103C on the water. You should not be reaching that sort of temperature on the street.

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

    • ok so if i wanted to go 18's i would go for 8's  in front 30+ or 32+ off set at front and the back 9 would be ok? what offset should i aim for.. then can i do some  hunting for wheel rim choices..    If i get this - will this fit all around: Size: 18 x 8.5 +37 - n what tyres size tyre should i get for front n back?  
    • Absolute f*cking nightmare. I had to take breaks constantly, and I was always pissed off when I got home. The line split in Italy on day 2 (we drove from the Netherlands), lol. Driving any narrow European town was... well, sh*t.   Appreciate it man. Here, I'll just drop a favourite from the load I took on Saturday.   I'll update here when things happen with the car, the thing is, with stock power and almost everything chassis-wise taken care of, there really are no problems. 268,000kms now and counting.  
    • Ah! I actually managed to snag a lightly used set.... that aren't so suitable for me right now. They don't work on a GTT without some cutting or creative heat moulding. I thought about reselling them myself cause I didn't want to murder them, but it looks like I'm probably going to attempt to murder them/melt them because I may as well. @GTSBoy @PranK can somebody close this thread?
    • Hey mate,  I have a set, one is slightly damaged but wont be noticable once installed.  Shoot me a message if your still after them 
    • I couldn't wait But, the black constant tension hose clamps were too thick and there wasn't enough clearance at the T/B and I couldn't get it to seat properly, so I had use a silver one there I also added some 3" silicone over the alloy bit that goes through to hole on the radiator support as it looked like it was sitting on the edge of the hole in the radiator support, I never noticed a rattle or anything, but there was a witness mark It is basicly done, and I can live with the silver hose clamp at the T/B, I will get a black clamp for the head vent though where it is attached to the bulkhead fitting  It never stops...LOL, only issue now with the shock tower brace is it slightly touches the under bonnet liner now, if I leave it it will either wear some paint off the brace where it touches, or damage the liner, so I removed the liner to see what I have to work with, with the liner removed I have about 20mm of clearance, but sadly the middle part of the underside of the bonnet is only dusted with paint and looks crap, so I cannot have that, but.... as I have a roll of Carbuilders premium under bonnet insulation in the garage laying around that is only 5.5mm thick (we were going to use it on the boys Patrol, but he crashed the front of it a few months and it was written off, hence why he now drives my old Honda Accord Euro), I'll use the OEM liner as a template and get the Carbuilders stuff fitted up to cover that dusted paint up
×
×
  • Create New...