Overheating issue

[ETH4N]

Hey guys, i have a VS Vacationer V6 Automatic, its been over heating, it got a new radiator, and when the aircon was on, it would stay nice and cold, but the aircon has stopped working, and now when i idle at lights once the car stops, it rises, and gets hot, until i start driving again, and then it cools back down, so only heats up on idle when warm... sounds like the fans are kicking in, but im just wondering, what are the main causes for this?

 

[HamaTime™]

This is normal. Airflow is not the best on VS's, and it's normal for VS's to creep up to 3/4's on the Temp gauge when sitting in traffic. The Thermo should kick in around then and cool it down. The reason why the aircon keeps it cooler is because the fan is on which keeps the motor cooler.

Keep a close eye on your radiator fluid level, and your overflow bottle level. Keep them topped up and flush your cooling system every 15-20,000.

Keep them well maintained and they don't break.

 

[ETH4N]

Oh really?, i thought it should stay low like when the ac is on....ok, ill just sit and watch it

 

[HamaTime™]

It does. It stays slightly cooler when the AC is on for obvious reasons.

 

[hako]

It's normal for many VS temp gauges to register 3/4 when stationary before the fans kick in, whilst normally the gauge may read 1/4 when the car is moving. What you describe sounds pretty normal.

 

[tim005]

my vs ute does this exact thing.
goes 3/4 to the top when stationary, even when its marginally warm weather.
i start driving and it goes back down again, its so so so annoying.
i have got a new radiator and water pump a few months ago.
got it pressure tested, no leaks.
my mechanic is stumped, we have no idea.
i have to live with filling it up once every week in warm weather and once every 2 weeks in colder weather.
next step is taking the thermostat out for summer, when we bought it was stuck open.
maybe thats the answer?

 

[delcowizzid]

its normal the fans dont come on till over 100 degrees

 

[Brett_jjj]

Ive read on here that a few people have changed temp senders and this has fixed the problem.Apparently holden released a revised temp sender unit for the VS because some senders were showing too high of a reading on the temp gauge. I wouldnt like my temp gauge running up there at 3/4, it doesnt leave much room for error .Id be worried that I wouldnt notice it in time.My VS sits around a quarter,maybe up to half way when idling for a while,never over that though..

 

[hako]

my vs ute does this exact thing.
goes 3/4 to the top when stationary, even when its marginally warm weather.
i start driving and it goes back down again, its so so so annoying.
i have got a new radiator and water pump a few months ago.
got it pressure tested, no leaks.
my mechanic is stumped, we have no idea.
i have to live with filling it up once every week in warm weather and once every 2 weeks in colder weather.
next step is taking the thermostat out for summer, when we bought it was stuck open.
maybe thats the answer?

When you say that you fill it up every week in warm weather, do you mean the radiator is empty, or down a bit, or do you mean the overflow is empty? If you are concerned about it reaching 3/4, you can fit an over-ride switch and manually turn the fans on when you think it is getting hot.
The coolant must be going somewhere. I've found it easier to check an engine for coolant leaks in the dark with a torch....do this with the engine running but keep clear of the fanbelt!
Have you checked the heater tap and the heater element for leaks....also if it's running a bit rough every now and then it could be an inlet manifold leak.
Removing the thermostat will achieve nothing and possibly make it run hotter - google thermostats and read why you should not remove them.

 

[tim005]

When you say that you fill it up every week in warm weather, do you mean the radiator is empty, or down a bit, or do you mean the overflow is empty? If you are concerned about it reaching 3/4, you can fit an over-ride switch and manually turn the fans on when you think it is getting hot.
The coolant must be going somewhere. I've found it easier to check an engine for coolant leaks in the dark with a torch....do this with the engine running but keep clear of the fanbelt!
Have you checked the heater tap and the heater element for leaks....also if it's running a bit rough every now and then it could be an inlet manifold leak.
Removing the thermostat will achieve nothing and possibly make it run hotter - google thermostats and read why you should not remove them.

the overflow tank is almost to the point where it is bone dry, the radiator takes in water but not full capicity.
the car never runs rough, we initially though an inlet manifold gasket but after a visit to the mechanic he said all that was tip top.
it has us stumped...