Vy Overheating issues

[Amy Winslade]

Back again and I'm about to go insane. The same issue is happening. Cannot take to a mechanic to "diagnose" because I just do not have the money...

Overflow tank has coolant (isn't over full) ... Coolant in the radiator also.

Top hose is boiling hot but has ABSOLUTELY NO COOLANT in it and when the hose is removed steam comes out.

There are no air locks.

Water pump has been replaced

Thermostat has been replaced multiple times and works. Has even been removed temporarily and still had the same issue.

Bottom hose is full of coolant.

Coolant is the correct colour.

System has been bled properly multiple times.

WHAT IS HAPPENING?!?!
thank you everyone for your help.

 

[Immortality]

Silly question but is the serpentine belt fitted correctly?

Failing that it would suggest there is a blockage somewhere.

 

[Amy Winslade]

I neve

Silly question but is the serpentine belt fitted correctly?

Failing that it would suggest there is a blockage somewhere.

I never thought of that. .. If it's worn or cracked or not fitted correctly this causes the water pump etc to not function as they should... Is that correct?

And if it's not that would the next bet be the radiator?

 

[Immortality]

If you have run the engine without the top radiator hose fitted with the engine up to full temp and no coolant has come out then there is a flow problem.

The owners manual has a diagram of the correct routing for the serpentine belt.

 

[Gridlocked]

Thermo fans running when aircon is on? I've replaced several fans over the 14 years I've had my VY. Temp shoots straight up if the fans are inoperative. From memory it was the large fan that is always on when the aircon is running.

 

[lowandslow]

Is there coolant in the top hose when it's cold? Stick a funnel in the top of the radiator, open the bleeder and top up with coolant until it is running out of the bleeder.
You sure the thermostat hasn't been fitted arse about?
Serpentine belt fitted the right way so it's turning the water pump the right way?
I had a bit of trouble getting the air lock out of my V6. Needed the coke bottle trick at operating temp with the heater on hot to push all the air out of the bleeder.

 

[Lachy Saunders]

Hi I am also having this issue, I own a vy sv6 and when just driving it will tend to go all the way into the red, if I was to swerve or brake aggressively the temperature needle will drop back to its usual spot, I have replaced the thermostat and water pump entirely as well as new hoses.

 

[lout]

when you cook the engine
you will think the mechanic to diagnose would have been cheap

 

[87VLCALAIS]

Back again and I'm about to go insane. The same issue is happening. Cannot take to a mechanic to "diagnose" because I just do not have the money...

Overflow tank has coolant (isn't over full) ... Coolant in the radiator also.

Top hose is boiling hot but has ABSOLUTELY NO COOLANT in it and when the hose is removed steam comes out.

There are no air locks.

Water pump has been replaced

Thermostat has been replaced multiple times and works. Has even been removed temporarily and still had the same issue.

Bottom hose is full of coolant.

Coolant is the correct colour.

System has been bled properly multiple times.

WHAT IS HAPPENING?!?!
thank you everyone for your help.

Most definitely check the routing of the belt to ensure the water pump is turning the correct direction.

To my way of thinking if there's no water in the top hose then there's probably no water around the thermostat which means it probably won't open. It also means you likely did have an air lock.

Get a plastic drink bottle cut the bottom off it and fit a piece of soft foam tubing (something like foam insulation tubing) over the neck of the bottle and jam it into the radiator filler making sure the foam tube is a snug fit into the radiator filler neck.

You need to do this so to be able to get the water level at the filler neck high enough to purge any airlock. Using a bottle in this manner allows you to partially fill the bottle thus giving a head of water at the filler.

Then run the car and top up the radiator via the upside down bottle. When hot water starts to flow in the top hose (i.e. when the thermostat opens) open the bleed screw on the thermostat housing to let out any trapped air. Once water starts flowing out of the bleeder, shut the bleeder for a while then re open to let out more air. Keep repeating this till you stop getting air at the bleeder.

One thing to check is the bleed hole inside the thermostat housing. This is beside the thermostat. If the gasket isn't fitted correctly it could be blocked. If it's blocked it will prevent the system from being properly filled and potentially leave air around the thermostat.