Garden hose and running engine?

[Clacker]

I'm about to change coolant on my VS and my bro's VY. His water is particularly dirty so I want to flush it properly to get all the shit out.

I'm gong to clear out the block, radiator and heater core as written here but I'd like to then run the engine with the hose to really give it a good flush.

I know the heater core on the VS does not get hot unless the vacuum opeated switch is engaged (I assume this is the same with the VY) so I figure the engine has to be on to be able to fully get all the old coolant out.

Question is, is mains water pressure more than adequate to ensure the water pump doesn't dump it faster than what the hose can add?

I was planning on pumping the water in through the thermostat cover (removed) and exit from the bottom outlet on pass side of the car.



Any thoughts or suggestions?

Thanks

[HICOMPVN]

garden hose pressure is not enough to flush!!!!

[azzfox]

whoa whoa hold up. thats not necessary. all your doing with the engine running is driving the water pump. now, the water pump collects water from the LOWER radiator hose, so reverse flushing (hose in top of motor) has fail written all over it. plus cold water circulating through a motor thats trying to heat up isnt a good idea at all. it doesnt take much for cast iron to crack.

I suggest reverse flushing with thermostat removed, flush the heater core separately, remove the radiator and reverse flush that too. then put it all back together, fill with water and bleed. go for a short drive with the heater on full until the car warms up. allow to COOL again before dumping the water and replacing with coolant. you may also repeat the flushing process again depending how dirty it is. oh, and dont let it sit dry for a long time, especially the radiator.

[HICOMPVN]

i suggest you head to super cheap/repco/burson's etc and enquire about getting a radiator flush kit, uses water and compressed air to flush all the shit out, used to use one all the time when i used to work at justtoyota in moorabbin, i think there not to expensive. here's some links

"Radiator Products" (scroll to bottom of page)

Prestone :: Products : Prestone®Flush N Fill Kit

or Go to your local auto parts store and tell them you want a coolant system flush kit

[Clacker]

Thanks guys, this was the info I was after.

Getting the coolant out of the heater core was why I wanted to run while engine on but I'll fill with clean water and then start to open tap and circulate, let it cool down and repeat until clean.

[azzfox]

Just pull one heater hose off and stick the garden hose in it, which a plain garden hose fits quite well. I just usually pull the hose off the pipe at the pump (heater return), then just let the tap water flow though the heater core, into the motor and out the lower radiator hose like the rest of the old coolant. Just remember to set the heater controls to full hot. There will be enough vacuum left in the system to allow the heater tap to stay open without the need to start the car.

[aceventura]

Heater tap is actually open under atmospheric pressure - it closes under vacuum.

[Clacker]

Thanks guys.

That's great the heater tap isn't an issue when the engine is off.

The top heater pipe seems to connect just below the thermo housing at the top of the engine. Does that mean I could use that connection to flush both the heater core and block?

Thanks

[subieboy]

Use the search function mate! Its the first thing I found on this site when I got my VS and it has step by step instructions.

How To Flush A V6 Cooling System