Cooling System Issues?

[33gtst]

Im hoping someone can shed some light on the emo cooling system in my r33.

I'll give a quick rundown, prior to water pump install, it would operate at half on guage in traffic and reduce down to anywhere to around a 1/4 dependent on airflow/outside temp etc etc.

But now after the water pump install, its behaving differently, which may not be cause to be concerned but its different...and I dont like it being different.

It now sits at half all the time, and if in traffic tends to drop a little on the gauge(just under half) I am not using any coolant, and cant see any visible leaks. But after the last water pump smashing to the shit, in my paranoia all I can smell is coolant at the front of the car. But despite cleaning it, after the failure, im putting this down to residue.

I have removed the rad cap and its not showing any signs of head gasket issues, bubbles or the like. However after the failure my clutch fan did develop quite a few large cracks between the fins, but surely this wouldn't affect the temps being reduced when airflow is greater? or would it? I have an aftermarket no name radiator.

It happened not immediately after the water pump install, I went for a drive and it was sweet then all of a sudden (probably about 80kays later) the water temp increased and has slowing continued until now its always at the half mark, even coasting down a big hill in 18 degrees do not alter the dash gauge.

Any ideas as to where I might start?

With much thanks,

Danielle

[Craved]

did you do the pump replacement, or have a shop do it?

sounds from your description that the car didnt have a thermostat before and now it does, the car should sit just under half at all times, regardless of outside temp.

[33gtst]

for real?

My friend also has a 33 and his will drop down in temp subject to airflow to around a 1/4 as well. A shop installed the pump, and needed a couple of go's to get it right, there is no way they changed the thermostat, that area has not been touched on that engine ever id say.

Does any one know what the actual heat range is of that gauge?

where does everyone elses rb25 sit on the gauge?

[blind_elk]

I've got a RB25DET in my 32, and the temp gauge has always sat around the halfway mark (even 40+ with A/c on full blast).

You (and your friend) might have a sticky thermostat that doesn't open / close smoothly. I don't think it will hurt the replace it, anyway.

[gotRICE?]

The bottom line is, the temp gauge shouldnt move unless the car is warming up from cold, or worst case, everheating!

The thermostat controls the temp and keeps it at "operating temp".

[Jmaac]

Not sure if you touched the radiator cap but its possible its starting to fail or is the wrong one. Heres a lesson, an increase in cooling system pressure raises the boiling point of the coolant, this prevents the flashpoint conversion to steam when near cylinder hotspots thus better cooling (higher altitude also reduces atm pressure and lowers boiling point). That smell could be the cap opening prematurely and flushing coolant out of the overflow. Put a new stock cap in or one rated a little higher (not as cold as japan here so dont need the heat). Dont go too high because if the pressure release is rated to high it can burst hoses etc.

The clutch on the fan is could be gone also

My 2 bob

[76GTR]

Hi Danielle, My r33 temp gauge sits just under (bee's dick) halfway at operating temp. The thermostate regulates the temp of the coolent in the system. I would remove the thermostate and test it, to be on the safe side. it sound like the thermostate has been sticking open at times before the water pump was done. My fan has a couple of cracks in it as well, thats just from age. If they are really bad replace the fan. I have worked on many nissan vehciles over the years and i've found the temp gauges on various models to site about halfway or slightly under at operating temp.

Regards

Clynton

[33gtst]

Thanks for the replies.

Seems like its nothing out of the norm, so nothing to be concerned about...I guess im a little paranoid after smashing a water pump.

Yeah looks like fan is on the to be replaced list. Ah at least thats easy to do!

Cheers again guys.

[br3ndan]

mine sits at bit unde rhalf way no matter how hot or cold.

As this is the optimum engine temp.

So iwould say b4 it wasnt acting normally due to failing pump and now its fixed and working normally

How did u smash your old one? or do u mean it just failed due to age?

[TKR]

general rule with old car's water pump + thermo ( any issues with cooling cant be solved) but sounds like your thermostat isnt operating to spec maybe..

[WOO32]

by the sounds of it ur thermostat is faulty, she should stick around the half mark but seeing that were on cooling system issues does anyone know what temp the right "opperating temp" should be? i just did a thermo fan conversion and im not sure if 85c (when the fans kick in) is the optimal temp.coz ever since then she seems to be using more fuel...

[Craved]

my pfc reads constant 89C