VE SS Overheating idling any help be grateful

[Skaa]

I havent driven this car much lately probably twice a month Id take it out the garage. Was driving around for about an hour running a few errands and she just overheated into the red n threw a coolant temp high warning while I was sitting in idle at some traffic lights. I got moving and the temperature came back to normal as to be expected.

Was no coolant missing when I let it cool down n took radiator cap off.
I did notice only the drivers side cooling fan was working even when the temperature climbed up again toward the red at idle the passenger side cooling fan never kicked in at all.

I let it cool back down
I started her up from cold, idled it for 10minutes no problems at all temp just stayed at normal,
I then drive a couple kms n pull over again to let it sit in idle another 10 minutes temperature still sat at normal,
I drive another few kms then stop n let it idle again and after a few minutes suddenly the temp gauge goes up into the red again

Iv got a Hi Flow thermostat in it probably be a few years old now
Anybody got any ideas as to whether I have a cooling fan issue with passenger side fan not kicking in or whether it just works at highway speeds not sure bout that 1
Or a thermostat sticking or faulty radiator cap I'm not too sure why its playing up n overheating on idling sometimes and not all the time I'm idling

 

[Benboy]

If the cooling system has not been regularly maintained (flushed etc) it is likely that your radiator or water jacket may be blocked or flow impeded - perhaps because the car has been sitting unused. You may have to go to an Engine Cooling Specialist for a flow test etc. Good luck.

 

[Skaa]

Yea I did an engine rebuild recently on it but forgot to change the water over to the coolant again after I ran it in n checked for leaks. Water did look pretty ****. You're prob right on the mark there, il get it flushed out thanks man. That passenger side fan is it meant to work with drivers side or comes on separately?? I couldn't remember off hand

 

[Bigfella237]

Why did you start two separate threads ten minutes apart? Perhaps contact a moderator to see if they could combine the two for you?

(see other thread here: https://forums.justcommodores.com.au/threads/ve-ss-overheating-idling-any-help-grateful.256037)

There could be many reasons behind this behavior but after reading about your recent rebuild, the first thing I'd be looking at is air trapped in the cylinder heads, are the steam vent tubes connected and not blocked?

Do you still have the heater circuit connected (to bypass the thermostat when it's closed)?

Both fans are connected to the same circuit in a VE but each relies on the resistance of the other to run in low-speed mode so if one fan is disconnected you will get full speed or nothing at all on the other.

From the VE service manual, this is the wiring diagram for the cooling fans:

And this is the circuit active when the ECU commands low speed:

Note that the two fans are connected in series. And this is the circuit active at high speed:

Note that the two fans are now connected in parallel.

 

[Skaa]

Lol I'm not too sure why I ended up replying to 2 separate threads. Iv Stuffed up somewhere there. Thats great thanks for that info, I ran engine up with water n forgot to put the coolant back in, water looks brown n prob clogged up my radiator sitting il run a chemical flush thru it get the water clean again n put coolant bk in it. Iv driven it for 1000kms round Sydney since no overheating till now

 

[Steven01]

Have you checked your Radiator cap and your Radiator fins for damage. To me sounds like Radiator cap may be stuffed and worn rubber seal and spring can pushing itself into cooling line and restricting flow.

One way to test if fans are working is on passenger side on the block is a cable pull it off and both fans should run at full speed when you turn car to acc or even start car.

 

[redvxr8clubby]

If it's only a problem at idle, I would think checking the fans would be a good place to start. Once you start moving and the temp comes down would suggest fan problem.

Excellent detailed post by bigfella with the fan diagram, I think that would be very useful, not only to the OP, but also for anyone doing a future search, well done bigfella, very useful info there.

 

[pebbs]

Re engine rebuild, can you tell us how many Ks were on the vehicle prior to the re build please and the cause of the re build , eg poor servicing?
Just interested in how a late model car needs a re build so quick.

 

[Skaa]

The rebuild was done at 180,000kms cos a pac valve Spring broke less than 20,000kms later n dropped its valve on my new cam. The retailer payed up for some of the parts. I sleeved the stuffed cyl and replaced with dual valve springs