opinions needed. Is my car too hot

DouglasB

DouglasB

Member
opinions needed. Is my car overheating or lying

So got myself a new car. It's a 1JZ s13. Car has a digital dash and an aftermarket temperature sender in the outlet pipe at the top of the rad. I've checked the sender in boiled water and it reads fine.

The car has just had a new supercool rad and 2 12 inch mishimoto fans. It's also had a new thermostat. All done by me in the last 2 weeks. The car still appears to be running hot but I'm convinced it can't be. Driving along normally it reads 92* then I boot it and it shoots up to 105* sometimes a little more (106/7). If I do a donut or skid a closed course roundabout it will go even higher.

I'm convinced it can't be overheating. There's no leaks in any pipes and everything is new that could cause a problem.
I'm thinking it's just shooting up because the temperature is being read from the outlet pipe rather than the factory sender on the water pump which is just off the inlet.

Am I right in saying the water SHOULD be fine going in but then obviously the heat from the boost has to go somewhere.. water Is then going through the engine being heated up and being shown on the temp sender at the outlet?

Got my first drift day with it tomorrow and don't want to blow it up :(

Any opinions are welcome
 
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* I bought the car from Southampton with an 8 hour drive home... surely if it was actually overheating it would have blown by now? This was before any cooling modifications*
 
its possible it could be overheating, I'm currently building a R32 1JZ although its not running yet I've been forewarned about it running hot.

JZ engines are usually in a larger engine bay with a lot more circulation than that of an S/R body.

I've gone for 4 fans two either side of the rad as unfortunately I cant run the viscous.

I wouldn't be surprised that when your going sideways its getting hotter to be honest.
 
I've cut holes in the bumper and put a bit of pipe from fog light hole to rad.

The whole front end is tubbed so plenty air SHOULD be getting in ha. Really hoping to move the temp sender even if it was to the inlet pipe. Not sure if that would work though?

Just replace the top pipe and put the T piece in the bottom pipe?
 
I'm confused.

It is overheating? 105 is way too hot for a bit of spirited driving. the fact it isn't pissing out water or blowing smoke does not mean it's not overheating! I'd have a serious look at it before taking it to a drift day

The fans working? A picture of your setup might help.

The "heat from the boost" comment I have no idea what you mean. Boost is compressed air.
 
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Will go take a picture just now. Booted it.. went to 101. Water is going into the expansion as steam so definitely overheating.

Fans are definitely working as they are on a circuit with my power steering so if they stop working so does my power steering .

Heat from boost... meaning when you go on boost the turbo's get a lot hotter making the bay/engine a lot hotter
 
Really wanting to drift it tomorrow so gonna drill my bumper behind the plate... plate off and see how that goes.

Then gonna try make a ghetto spec inner arch that will push air into the bay rather than going right under ?

If it's still running hot I'm not gonna drift but I will need a solution. Really can't think of anything else. Makes no sense
 
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Im running 2 kenlowe fans and a supercool rad on my s15.

Driving temps average around 80, but i haven't drifted it yet.

My rad is placed in the standard location but my bumper has a big undertray which might help. Also running a nismo style vent.

Edit: also i dont think i have a thermostat!
 
Running up to 110 is not unusual at all most modern cars run that hot , they don't put fans on till 100 , push fans are not as good as pull , most std gauges show middle on gauge even when over 110 , do not remove the thermostat!!!!! As the water does not travel round the engine correctly without it . Lower temps are better but I would not worry unless it keeps climbing
 
The 2 fans on just now are brand new mishimoto's. They work as push or pull. Currently working as pull fans.

Tinker... presuming that's to do with pressure that's created from the thermostat being present.

The outlet temp is reading over 100 and it's steaming into the overflow. Not feeling great about drifting it if it's boiling.

If the temp is usually read from the water pump, which I'm presuming is running a good temp, then surely the outlet reading I'm working from is irrelevant?
I've been told from a garage who regularly builds/works with JZ swapped cars (not in much detail as it wasn't why I seen him) that the temp sender is in the worst place. Could this be because it's reading an irrelevant temperature? But then to me boiling expansion tank = overheating
 
Does the radiator have a big enough surface area to adequately cool the engine? It looks pretty narrow to me. Also above, if you have 4 fans running are they all working in the correct sense, i.e. in front of the rad pushing, back of the rad pulling?
 
Reading temps from the head is normal , as that's where it is hottest , the return pipe to the over flow / header is sometimes called the steam pipe as it vents steam , the rad cap makes pressure to raise boiling point so when it vent it will be steam , if you could get rads behind rad it would be better !!
 
Spoke to the guy who built the car. Be said he's had the same sent up and only had it on track getting driven hard. Never had it over 100.

The rad is the same size as what was in before



If I could get rads behind rad? Are you meaning the fans?
Then are you meaning having the fan between the engine and rad rather than between rad and bumper? Then have the fans pushing hot air back against the engine so that heat can't reach the rad?
 
Im going to say your going to have next to no flow over that radiator and the air you have is already hot from the oil cooler or intercooler. The other thing is you have 2 big fans on the front of the rad blocking all the flow you get more air hitting the rad driving that those fans will suck.

most of the 1jz conversion s ive seen seem to run the bigger thicker rads
 
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