A good write up but there seem to be quite a few differences between those photos and a Commodore. We do not have a radiator drain plug or a radiator cap just to name a couple.
+1 no radiator cap on my VX. So what's the best way to totally drain and flush the system on a VX LS1?
On the VT VX #drain... have the heater set to high run the motor for a min and then get a suitable bucket place under lower radiator hose, undo the lower radiator hose. #flush take off the in and out heater hoses and with the garden hose or if possible pressurized soft water flush the heater box until it runs clear then remove top radiator hose and stick hose in lower opening and back flush the radiator, then if need be flush the block, then refit everything. and add red coolant (better for alloy blocks) mixed with soft water which include rain water, De-mineralized water and distilled water. The LS1 will self purge the air out when in park hold at 1.8k for a couple of mins with the overflow tank lid off.
I just flushed the engine with garden hose untill clear water came out. My vapour pipes that go from the heads to the radiator were completely blocked. The Ls1 is designed with an automatic bleeding system. It does not have a bleeding screw on the thermostat. Instead it has vapour pipes attached to the top of both heads (highest point of engine) which connect to the radiator. Then there is a top hose on the radiator that is higher than the vapour hose that goes to the overflow tank. Air goes to the highest point, so the air in the radiator goes to the reservior, and the air in the engine also goes to the reservior by the vapour pipes. This way the car bleeds itself. So back to the point, my vapour pipes were blocked and I had to wire clean and blow compressed air in to them to clear the blockage. If these are blocked then air is trapped in the engine and it will overheat at some point. To simply check If yours is open, just disconnect the hose from the vapour pipe end (not the radiator end) and see if coolant comes out. If not then yours is plugged. Thanks user undar8ed1, I am going to follow your instructions to purge the air like you said "The LS1 will self purge the air out when in park hold at 1.8k for a couple of mins with the overflow tank lid off."
Vy too. They went back to them for some reason on the vz. Be careful flushing with the hose in Australia, your water is quite corrosive
FIXED: Overheating. Yea it was the vapour pipes that were not allowing the car to bleed. I fixed it and I let the car sit for one hour with the AC on, and the car maintained temperature and the needle did not go up and down but was steady. The car ran cool as ice. Before it use to overheat with the ac on and the temperature use to bounce up and down.
where's the heater hoses/box and which one is in and out? How do you flush the Block? Thanks for the instructions. Sounds fairly simple except I don't know where the in/out heater hoses/heater box are located or what they look like? I do understand the steps to flush the radiator. But how do you flush the block? Sorry mate, I'm no mechanic. Closest I ever got to anything mechanical was fixing a BMX bike! If you could just fill in those details, i'd greatly appreciate it! thanks champ!
Hey I have done that exact thing and my temp gauge fluctuates. Sometimes the coolant is pressurized and will buoy up and down on throttle control, I think there's a blockage in a few pipes but I can't seem point my finger on it.. I let it idle for a few minutes and drove it for a bit and it sat under half on gauge, then just rocketed to over half.. its as if there's a block somewhere and the engines not getting enough coolant .. help ?
