Look at this picture..Is this too high

[albert_ey]

yup, my 73 never goes past the halfway mark, I have an OEM Nissan thermostat. The radiator is the stock one, it stays cool all the time.

[beandip]

I don't think any one has asked. Are you using any antifreeze ? This helps cooling the engine also and provides a rust preventive. Since you live in the South maybe you haven't thought of this. I recommend on the OEM stat also. My L-24 never went past the center of the gage even at triple digit temps. Now with the ZX engine in the same car with a 2 row stock radiator she didnt over heat either . I now am running a 280 3 core and the same is still true. the old '73 radiator needed repair so I replaced it . Not because of over heating.

[deadflo]

What about the possibility of incorrect temp sensor readings? You mentioned you had just changed out the t-stat before it read high. Have you switched back to an OEM stat yet? I ask because I know have exactly the same issue. I recently switched out the stat in my 280-ZX when the aftermarket one caused it to run too hot. The OEM 180 degree stat solved the problem in that case.

My 240-Z had been running hot on the temp scale just like yours, after my mechanic switched out one that was stuck closed with an aftermarket.

So I just replaced that one with the OEM 170 degree one.But its still showing hot on the guage. I borrowed one of those laser thermometers from my mechanic.It reads around 175 at the top of the stat housing when it is warm, despite the real high reading inside the car on the guage.I assume I now need to switch out the sensor now to see if that is the culprit.

[mally002]

Still waiting on a new OEM t-stat that I ordered last week. Pulled off all the old a/c equipment and still trying to install the new electric fan...(see other thread, as I'm still having trouble). Hopefully by next Wed all will be back on and the results will be good.

I'll post how it works soon.

Thanks

[Mat M]

What about driving without thermostat?????????????

Here is the HybridZ approach to running an L28 with no thermostat:

http://forums.hybridz.org/showthread.php?p=775386#post775386

No consensus there, either.

[Arne]

Here's an interesting addition to this thread. I drove my yellow car a bit today. It has a stock L24, and the entire cooling system is new. New 3 row radiator, all hoses, heater core, sending unit, thermostat and housing, everything. Has a larger diameter 260Z fan. But the thermostat is not OE, just a cheap aftermarket that came with the parts car when I bought it. With my entirely new cooling system, my gauge runs about where yours did in the first picture. That's at 80 degrees (F) outside. If the OE thermostat helps yours, I'll be after one as well.

[mally002]

Arne,

I just tracked the shipping of my oem thermo and it will be here on Thursday...a 160 degree. Hopefully I'll have it in and running by Friday and let you know how how it performs.

On a side note, I did run the car about 8 miles this weekend without any thermostat and it ran cool until I had to stop and idle for about 45 secs. In that time it got hot again, not 3/4 over but a little past halfway. I'm sure the new thermostat will help, but I'm also replacing the radiator and installing an electric fan.

[bandoni]

I replaced my thermostat for an oem 180 degree thermostat, and replaced my fan clutch and i am still a overheating a little. like about a little bit over the halfway mark, after highway driving about three quarters to hot. ambient temp outside was 110 with little humidity. any ideas?

[deadflo]

Hmm, well if I got that right the guage reads at three quarters when it was 110 degrees outside? That doesnt seem to be overheating in my book, Again, I wonder how accurate the guage is. There was that link in this thread to calibrating your temp sensor by the resistance reading.

You could try using one of those laser thermometers and pointing it at the top of the ermostat housing when it is wamred up and seeing what your reading is. To me overheating is when the guage reads REAL hot. But I dont think it sounds like overheating with the reading your getting and it's 110 degrees outside.