How to flush cooling system?

[Roler]

Originally Posted by bruggz351

HAHA, yeah, I think he wants to know which location would be best, for drainage.

cheers

Aaah, good. Well, I'll leave that to the VM maestros...

[..dylan..]

haha yeah I was asking which to undo and in which order.

Thanks again fellars, I'll contact the above mentioned.

[layback40]

Originally Posted by anthonygubbin

PM Layback or Mud Monster and ask them to respond to the thread. They know all there is to know about the VM.

Regards A

Dont know if MM is about, I have been away for a while.

Flushing ~
Take the jeep for a run to get it up to temp with the cap loose.
Park the jeep so the right side of the car is highest.
With the engine still running turn the heater to max heat & then turn engine off.
Remove the overflow bottle , its held in place by a couple of screws & has 3 hoses going to it. Also disconnect the level probe. You can use a garden hose to flush it through the hose connections. I have used a bit of laundry detergent in it to get it clean. 1/2 fill it & shake it many times. Make sure you get all the detergent out, rinse out at least 10 times.
Disconnect the top radiator hose at the thermostat housing & the bottom hose at the water pump. Hold the garden hose in the bottom hose until clean water comes out clean from the top hose.
Disconnect the heater hoses near the thermostat housing. Flush heater until clean.
Put the garden hose in the heater hose connection that pipes into the thermostat housing. Flush till clean water comes out the bottom pipe on the water pump & the other heater pipe.
You can empty the heater core by blowing in one of the pipes (Bruggz you have a dirty mind ! )
I normally start the engine & run for a few minutes to let the water expel from the engine.
I am sure there are some drain plugs, I have never gone looking for them.

Its probably worth removing & checking the thermostat before refilling.
Worth replacing the fan clutch as well if it is questionable.

Before refilling, if the heads have not been tensioned in the past 50,000km, tighten all head bolts about 20 deg, you should need an extension on your socket breaker bar to do this. If any of the main head bolts do not appear tight you will need to go through the complete tensioning procedure as per the engine manual.
To do the simple retention, start with the LH front big bolt & work your way diagonally in a zig zag to the back & zig zag to the front. Tighten each of these by 20 deg. You access some of these bolts through the plug holes in the rocker cover.
Then tighten each of the smaller bolts (2 per head) each head at a time by 20 deg.
This will insure that you dont develop a head gasket leak from the flush.

PM me if you find loose bolts during the 20 deg tensioning & I can give you the full tensioning procedure.

To fill it, put the overflow bottle back leaving the cap off & connect all hoses except the top radiator hose. Fill coolant mix down the top hose through the radiator & so into the engine until coolant starts to come out the thermostat top hose connection. Reconnect the top hose. Fill the overflow bottle to about 1/2" below the neck& squeeze the top radiator hose to burp it a bit, adding coolant as needed.
Start the engine & allow it to warm up. Once warm check overflow bottle level & squeeze the top radiator hose in & out to try & burp it more.
Loosely screw the cap on. Take it for a run keeping an eye on the temp gauge. If you see it moving around a bit, stop & check the level.
Hopefully after about 30 km all should be good.

I have never worked out what is the correct position for the tap on the RHS of the top of the radiator. You can try it in both positions if you wish.

Others feel free to add to this.

[MattP]

I've been told it's a good idea to have the rear wheels on vehicle ramps or have the car facing downhill when refilling. That helps in keeping the coolant refill bottle above the level of the heads to prevent air locks. Hots spots due to air locks can cause problems with the sensitive heads. I believe there is also a drainage tap on the block below the turbo I but I could never get to it and relied on dropping the bottom hose connection to the radiator. There is also a breather/tap at the top of the radiator (drivers side) for bleeding.

[MattP]

Originally Posted by MattP

I've been told it's a good idea to have the rear wheels on vehicle ramps or have the car facing downhill when refilling. That helps in keeping the coolant refill bottle above the level of the heads to prevent air locks. Hots spots due to air locks can cause problems with the sensitive heads. I believe there is also a drainage tap on the block below the turbo I but I could never get to it and relied on dropping the bottom hose connection to the radiator. There is also a breather/tap at the top of the radiator (drivers side) for bleeding.

Whoops, posted before I saw the comprehensive response by Layback.

[layback40]

Originally Posted by MattP

I've been told it's a good idea to have the rear wheels on vehicle ramps or have the car facing downhill when refilling. That helps in keeping the coolant refill bottle above the level of the heads to prevent air locks. Hots spots due to air locks can cause problems with the sensitive heads. I believe there is also a drainage tap on the block below the turbo I but I could never get to it and relied on dropping the bottom hose connection to the radiator. There is also a breather/tap at the top of the radiator (drivers side) for bleeding.

You are far better to have it parked so the RHS of the car is high as that way the bottle is higher & the water manifold is high & its on the RHS of the engine. Also get yourself a small piece of wood about 1" thick & put it between the bottle & the brake booster. It tilts the bottle so that the cap is higher than the water manifold on the heads.

[Isaiah53]

Anyone know what the approximate capacity for the water is? Just wanting to make sure I get the coolant/water ratio right.