Hi all,

So I spent 4 hours on the weekend trying to remove the drain plugs on the block all to no avail! ?

I removed all the exhaust manifold & piping till the cat converter, I wasted about half a can of WD40 and some Permatex bolt loosening spray and they would not move. Tried using a 1/2 drive breaker bar and ratchet with a 14mm double hex socket and now the head of the bolt is a bit damaged. I've though of destroying the bolt by drilling through the centre and then replacing the bolt, but I do not have a strong enough drill or enough to space in the bay to do so.

I would like to completely drain out the coolant from the engine bay as the coolant currently running is a mixture of genuine coolant with water. I had to remove the top pipe to be able to replace the camshaft o-ring. The factory clips on the pipe gave way when I was ages from home and about 3-4L of coolant came out. All I had in the car was water so I had to use that to cool down the engine and get home.

Is there any other to fully flush out the old coolant? If I keep filling the system with water until all coolant is flushed out then I'll be left with about 4-5L in the engine block. I'm planning to use Nulon coolant in a 1 part water 1 part coolant "extreme" mix so i'm thinking of flushing through water over and over until I see now more coolant coming out of the piping and just filling the radiator straight with 3-4L of coolant so then I should have the required mix of coolant & water. Good idea or not?

Cheers,
TK
Appreciate any help with this!

There is a trick do doing a good flush, you use one of the 2 hoses going to your filler bottle on the wheel arch, put a hose in one (I think the one to the thermostat?) then drop the bottom rad hose then should flush the whole system, I've done this a few times on mine and the girlfriends falcon and worked a treat, as I haven't done it yet on the magna I can't guarantee that this method will work on a magna

Would be worth to change all hoses when doing a flush if the hoses haven't been changed in a long time, I've seen some ones with rust damage on the wire that holds the pipe shape

Is there any other to fully flush out the old coolant? If I keep filling the system with water until all coolant is flushed out then I'll be left with about 4-5L in the engine block. I'm planning to use Nulon coolant in a 1 part water 1 part coolant "extreme" mix so i'm thinking of flushing through water over and over until I see now more coolant coming out of the piping and just filling the radiator straight with 3-4L of coolant so then I should have the required mix of coolant & water. Good idea or not?


I always do it this way. Those bolts are too hard to get to, and probably seized in solid. Don't want to snap one off, or crack the block now do we?

It's a good idea to remove and wash out the overflow bottle too.

Magnas dont have wire in the hoses, this is just a stupid ford and holden thing

Secondly, the above method will not work

The bungs are hard to get to and are tight but always use a single hex 14mm, I have never had issues getting them out but it does take some effort

Flushing through the hoses will not work as the thermostat will close when cold thus there will not be any flow, only way to flush like this is with a hot motor and a flushing machine

Thanks for the responses guys - appreciate the help.

I will get a single hex 14mm socket and then use a large pole to extend my breaker bar to get more leverage on that bolt. The head is a bit damaged so I'm a bit concerned that I may end up completely stripping the head. If that occurs I'll probably head down to my mates place and we'll weld on a spanner I don't care about and try to get it off like that.

Failing that I'm thinking of just disconneting the top hose and placing the tap hose into the raditor and run the engine until I only see clean water coming out the top hose. Once the water is in the engine, I was thinking of disconncting the tap hose and running the engine until no more water comes out of the top engine hose in which case I pour 4-5L of the coolant into the bottom pipe and the rest in the radiator. I can't imagine the engine will overheat if its missing a bit of water/coolant for few minutes. My fear with this tactic is starving the water pump?

Just remove the thermostat - leave the thermostat cover off whilst flushing. Also make sure you flush the heater. I'd stick the hose in each and every entry point on the engine...stuff rags around the hose to seal it and turn the hose on full. You can bet your bottom dollar that when you get a service and it includes "coolant replacement" they only drop the bottom hose.

I didn't know what coolant had previously been put in my wagon, other than it was green (excessively green, I thought).
So I diluted it by removing the bottom hose from the radiator, draining what I could & replacing it with plain tank water.
After a run I repeated this step.

The third time I drained the radiator, I also connected a length of garden hose to the throttle body. (The throttle body coolant hose has to come off anyway when refilling to expel air.) I used the hose that connects the garden-hose reel to a garden tap - about 1 metre of garden hose with a female connector (without a stop valve) at each end. Into one end of this I inserted a short length of coolant hose (it fits snuggly - be sure its cut square) & connected it to the throttle body. Then I used a garden hose to connect all this to the water tank & flushed gently until no more green was coming out the end of the radiator hose. Disconnecting the garden hose to the water tank, I then carefully poured coolant into the 1-metre length of hose while raising it above the level of the throttle body - using the female connector like a small funnel - until coolant was coming out of the radiator hose. It worked well, but I had covered the mudguard with plastic in case of drips. Then I reconnected the radiator hose & refilled as normal.

I believe I drained an extra 1.5 - 2 litres of old coolant by doing this. I did have trouble with air in the system - I think I was too quick to replace the throttle body hose before getting a good flow of coolant from there while refilling the radiator.