Running hot problems

[Tom_1569]

The ute seems to run a little to hot, cold weather it sits at a 1/4, but as soon as your in traffic, it sits at half way and above (to the next little line) where the thermo cuts in, but takes no more then 20 seconds for it to get that hot, its very quick.

Yesterday in the hot weather it sat just under half on the highway, and would get hotter if air-con was on.
It doesnt go past that little line above half way, so its not exactly over-heating, but Im not comfortable with it running that hot all the time.

So far the following has been replaced:
Radiator hoses, heater tap and core.
Genuine Coolant
New radiator (got worse, but old radiator was cracked)

Next on the list is Thermostat,
Confirm thermo cuts in at appropriate times (can someone tell me when its suppose to cut in)
Water Pump
A better radiator.

Any ideas, help?

 

[RATTLEHEAD88]

maybe a water jacket is partially blocked in the heads or block.

 

[Vee-ard]

Thermo cuts in at whatever spec thermo you buy.

You can get 88 deg. Celcius right through to 93 deg. easily

A reverse flush of the block is in order I would say.

 

[hako]

The theory is that a 82 deg thermostat begins to open at 82 deg......it will be fully open as the engine fully heats up but can be anything from closed (going down a long hill) or fully open (climbing the hill) and anywhere in between. It will constantly vary the size of it's opening depending on how hot the coolant in the block is. You can test it in a saucepan.
Commodores are designed to run rather hot - it's all to do with efficiency....so maybe what you are experiencing is normal.
Thermostats can test OK in a saucepan but when installed can be slow to react or stick and it's always possible for one to be faulty straight out of the box.

 

[Tom_1569]

maybe a water jacket is partially blocked in the heads or block.

That did cross my mind, but if thats the case, it can stay like it lol.

Thermo cuts in at whatever spec thermo you buy.

You can get 88 deg. Celcius right through to 93 deg. easily

A reverse flush of the block is in order I would say.

Reverse flush has been done.

The theory is that a 82 deg thermostat begins to open at 82 deg......it will be fully open as the engine fully heats up but can be anything from closed (going down a long hill) or fully open (climbing the hill) and anywhere in between. It will constantly vary the size of it's opening depending on how hot the coolant in the block is. You can test it in a saucepan.
Commodores are designed to run rather hot - it's all to do with efficiency....so maybe what you are experiencing is normal.
Thermostats can test OK in a saucepan but when installed can be slow to react or stick and it's always possible for one to be faulty straight out of the box.

Sorry, I meant what temps the Thermo fan comes in, not thermostat, I use genuine Thermostats, and its going to be replaced when I have time as I have a brand new one sitting here.

 

[Tom_1569]

Also, I noticed if I put the Aircon on before it gets hot it will run very cool in traffic and wont get near half. Yet if I put Aircon on, on the highway it sits just under halfway.

 

[linz]

sounds alot like what my car it doing atm and i have already replaced the thurmostat and flushed everything at the same time and new coolent but still dose the same thing.

 

[old mate]

i find my ute runs warmer in traffic, but the thermo fan does its job well so i dont worry about it. all the vs's i've been in seem to run warm in town, not sure on highway.

might be just how they are.

mine runs too cold on the highway, i think a new thermostat is in order.

 

[Tom_1569]

i find my ute runs warmer in traffic, but the thermo fan does its job well so i dont worry about it. all the vs's i've been in seem to run warm in town, not sure on highway.

might be just how they are.

mine runs too cold on the highway, i think a new thermostat is in order.

Yeah thats quite possible to, just doesnt seem right to me. The VT doesnt get as hot, and its pretty much the same running gear engine wise, just the VT has different cooling system.

 

[Not_An_Abba_Fan]

I had a VS for 5 years and what you describe is how mine ran. They run about 1/3 to 1/2 on the gauge, it's normal. VS gauges are not known to be terribly accurate either, they are just a guide. Maybe get a proper temp gauge and see what temp the coolant is actually at. But it sounds like a normal VS to me.