V8 Temps, Should I be concerned

[IRON8]

i bet it just needs a good bleed but will be worth replacing the thermostat

 

[wraith]

Do the simple things first.

 

[someguy360]

i bet it just needs a good bleed but will be worth replacing the thermostat

Yeah, will replace the thermostat and see how things go.

How would one bleed the V8 cooling system, I know they don't have a bleed nipple like the V6

 

[IRON8]

dunno, i normally have the engine running and drip feed the coolant down the heater hose which is the highest point of the motor until it gurgles all the air out but the last time i had a mechanic do it and its been mint..

 

[Trayner]

Yeah, will replace the thermostat and see how things go.

How would one bleed the V8 cooling system, I know they don't have a bleed nipple like the V6

I normally had mine parked in my drive way which is on a slant , with the radiator cap off with the engine running for a bit.

Mine never went past 1/2 thou , would be lucky even to see 1/4 on the dash at all

 

[wraith]

Yeah easiest way is to have the radiator as the highest point let the thermostat open and the coolant will drop put more in done.

 

[BlackVXGTS]

Sounds like you need to replace your water (coolant) pump. Make sure you get a genuine GMB (not GMH) pump. Relatively cheap (around $70 on eBay) and easy to replace yourself.

Don't take advice from V6 owners, the cooling system on Holden V8s is different to the V6. You don't need to bleed the cooling system as such. Because of the relationship between the engine and the radiator, any air in the cooling system makes its way into the coolant reservoir within a couple of days. Just fill the radiator up, turn the engine on with heater set to max and radiator cap OFF, and keep topping it up as the air bubbles to the surface in the radiator. When the coolant begins to overflow from the radiator, replace the radiator cap and top up the coolant in the reservoir to the MAX line. Over the next couple of days you may have to add some more coolant to the overflow tank as any remaining air is purged from the system, but after that the level in the overflow tank will stabilise. The level should be at around the minimum level when cold and the maximum level when hot.

 

[Deuce]

My gauge used to read 1/4max and even fall back off the gauge on the highway at nights.
I replaced the sender and now reads just over half and sits constant once up to temp.

Went over 3/4 and almost red once.
I had a full car, trailer on the back with VR4 Legnum on it (approxs 1800kg) and going up really long hill into high altitude. I could fell the power getting sucked out of it as the temp rose. Pulled over real fast to let that cool off!!

How does your power feel when your temp gets up?
What colour does your fluid look?

 

[someguy360]

Went over 3/4 and almost red once.
I had a full car, trailer on the back with VR4 Legnum on it (approxs 1800kg) and going up really long hill into high altitude. I could fell the power getting sucked out of it as the temp rose. Pulled over real fast to let that cool off!!

How does your power feel when your temp gets up?
What colour does your fluid look?

Fluids are all good.

To be honest I haven't noticed a loss in power when it gets hot

Thinking at this stage its either going to be Thermostat or Water Pump (the water pump is quite old)

Found the GMB ones on ebay for around $55 so might do that and the thermostat in one hit next weekend

 

[Immortality]

Could also be an airflow issue. Standard from the factory there is a plastic piece below the radiator that has a 90° bend (downwards). I was once told that this lip is there to assist with air extraction from the engine bay. The body kit on my Senator has this lip as well on the front so I guess it must do something?