Coolant Bubbling in block

[Quentin]

Hi,
MY2010 Calais Sportswagon 6.0 L76. Recent rebuild AFM/DOD delete with VCM532 cam, L98 lifters. Feels nice, goes well. However, the other day I did a shopping run, 6ks, so up to temp, then stops at the hardware store, supermarket, newsagent etc. 5 short stop/starts then home. Unloaded shopping then noticed what sounded like boiling at the front of the block drivers side. Gurgle gurgle gurgle. Bit of a worry after spending so much money on engine. Surprised me given a 20 psi radiator cap, gauge normal half way. I am thinking some air trapped in block after rebuild.?? How does one ensure the integrity of the cooling system on these engines, i.e a refill process to ensure 100% fluid?? Couldn't find anything useful in the manual.
Thanks in advance for any input. Quentin

 

[Immortality]

Boiling in the system is normally caused when the pressure cap fails. Replace the radiator cap for starters, bleed the system and see what it does.

 

[krusing]

Air Trapped in the block does sound correct,
And possible the Radiator Cap is faulty ?
Use the old "Head of Water" Method
Get a 2 Litre Coke or Pepsi Bottle, and cut the bottom off,
You may need to wrap some insulation tape around the neck to fit the Radiator filler, [nice fit, not a tight fit]
and turn it upside down in the Radiator,
Fill it with water, start the Car and let it get up to Temp,
You will see the bubbles disperse from the Radiator, and keep topping up the Bottle till you happy the air has escaped.

 

[lazyc]

I always crack the steam ports and then pull suction on that pipe to the radiator.
I don't trust them to bleed without help.

 

[Quentin]

I always crack the steam ports and then pull suction on that pipe to the radiator.
I don't trust them to bleed without help.

That's what I think has happened- haven't bled the system on reassembly. But unfortunately you are dealing with someone (me) fairly ignorant mechanically - where may I find these steam ports?

 

[Quentin]

Air Trapped in the block does sound correct,
And possible the Radiator Cap is faulty ?
Use the old "Head of Water" Method
Get a 2 Litre Coke or Pepsi Bottle, and cut the bottom off,
You may need to wrap some insulation tape around the neck to fit the Radiator filler, [nice fit, not a tight fit]
and turn it upside down in the Radiator,
Fill it with water, start the Car and let it get up to Temp,
You will see the bubbles disperse from the Radiator, and keep topping up the Bottle till you happy the air has escaped.

Thanks - will try the bottle method - just had a look at a 2 litre golden circle juice bottle - almost perfect fit.

 

[Quentin]

Boiling in the system is normally caused when the pressure cap fails. Replace the radiator cap for starters, bleed the system and see what it does.

hThanks - can you tell me how you bleed the cooling system?

 

[lazyc]

Front of heads at the top, 10mm bolt.
Crack em. Fluid will flow. Close em

 

[BlackVXGTS]

As far as I'm aware, you don't have to do anything special to bleed the air out of a VE V8 cooling system. The Holden VE service manual certainly doesn't show that anything out of the ordinary is required. Might be useful for the V6 but not necessary for the V8 (excerpt attached).