Water air lock

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Grit Valve

Grit Valve

2000 4.6 Vouge
Posts
12,465
Location
Plaistow
Oops nearly forgot hi chaps 1999 dse Had trouble bleeding the system this weekend I drained the rad changed top hose, due to old age, swelling and rubbing on the egr . Now I have changed rad in the past with no problems. The car was cold i had checked the bleeder was clear filled up ran engine whilst squeezing hoses, heater full on.

It got hotter and hotter and hotter red light on o ****
Let it cool down could hear water bubbling at top hose

So when cool I undone both hoses at top or rad. The water pump side I could fill a bit with water/ antifreeze the other side was already full with water . Started car waited hotter and hotter red light on no joy . Let it cool down lots of squeezing started again everything fine how bloody strange why are these so hard to bleed air out any one know any better ways???? as my arse was crapping it thinking h/ g gona blow
 
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Shouldnt be any need to squeeze hoses....thermostat working? Possibly squeezing pressure wrong way against the thermostat? Done mine thrice since ive had it and never had a prob doing it by the book.

Also check all connections. Air could e enterig the system that way an failing to pressurise.
 
aerofabrique said:
Shouldnt be any need to squeeze hoses....thermostat working? Possibly squeezing pressure wrong way against the thermostat? Done mine thrice since ive had it and never had a prob doing it by the book.

Also check all connections. Air could e enterig the system that way an failing to pressurise.
Click to expand...

I was squeezing as after emptying when I refilled through the expansion tank only 1 1/2 litres went back in I still had about two liters still to go in and the expansion tank would not lower to enable more water to go in even after I started car ??
 
So you only had 3.5litres out of the top block and rad from draining? Suggest doing a full drain and refill.

Connect it all up then fill the expansion tank to the line. Allow 10 mins to let it settle. Switch on and idle till operatig temp adding the mix as it goes down. Count your litres in and when stable switch off and allow an hour or so and top up as required. Assuming all your connections are tight and components working you shoul have no problems.
 
aerofabrique said:
So you only had 3.5litres out of the top block and rad from draining? Suggest doing a full drain and refill.

Connect it all up then fill the expansion tank to the line. Allow 10 mins to let it settle. Switch on and idle till operatig temp adding the mix as it goes down. Count your litres in and when stable switch off and allow an hour or so and top up as required. Assuming all your connections are tight and components working you shoul have no problems.
Click to expand...

I didn't really need to change the water just top hose so I drained rad, undone/ changed hose. i had half a black bucket full about 3/1/2 litres did not wait 10 minutes maybe that's why always thought you run engine and water pump pushes it through whilst topping up ill try waiting next time thanks
 
Yeah sometimes its best to go back to square one. Apologies if sounded like teaching to suck eggs but in your situation thats what id do. Last one on mine was bottom hose replacment and managed with just draining the rad to. Still took on about 5/6 litres though.

Let us know how you get on...otherwise you maybe looking at other duff components. Its bad if youre overheatig at idle and no load.
 
I finally did it maybe the waiting for it to cool down allowed fluid to make its way into all the nooks and crannys but thanks all the same .
 
Heater on or off makes no difference, there is no water valve in heating system. Water flows through matrix at all times. Some thermostats don't have a bleed hole in them, this can cause airlocks when refilling.
 
wammers said:
Heater on or off makes no difference, there is no water valve in heating system. Water flows through matrix at all times. Some thermostats don't have a bleed hole in them, this can cause airlocks when refilling.
Click to expand...

Ok thanks on heads up on heaters I always put fully on to disperse any heat build up . Wammers would this make sense head had Hardly any water thus not allowing t/ stat to open thus not allowing water to circulate ??? As I said filled expansion tank but after 1/ 1/2 ish litres would not allow me to put any more in,thought if I start it water pump should push it through but level just sat there in expansion tank would not drop , after to over heats red light on lots of squishing of pipes third try after cool down finally didn't overheat and allowed me to top up tank was rather strange if must say so ..,
 
It is a funny system as the water flows in and out from the top of the rad. So you cannot get any coolant into the rad until the block overflows into it. Normally you would fill as much as possible through the header tank then start the engine and continue to slow fill burping the hoses as you go. Of course first making sure the rad bleed hose is clear. If the rad has been drained i like to use a spare piece of hose and fill the rad separately then fit top hose to rad, saves a lot of trouble.
 
wammers said:
It is a funny system as the water flows in and out from the top of the rad. So you cannot get any coolant into the rad until the block overflows into it. Normally you would fill as much as possible through the header tank then start the engine and continue to slow fill burping the hoses as you go. Of course first making sure the rad bleed hose is clear. If the rad has been drained i like to use a spare piece of hose and fill the rad separately then fit top hose to rad, saves a lot of trouble.
Click to expand...

Agreed fancy putting the water pump feed hose at the top of the rad no gravity to help things along I did check rad in the end but by that time it had worked its way in but defo will self fill radiator next time
 
defender300td1 said:
Agreed fancy putting the water pump feed hose at the top of the rad no gravity to help things along I did check rad in the end but by that time it had worked its way in but defo will self fill radiator next time
Click to expand...

Method is to fill header tank right up to the neck initially then when stat opens that excess coolant is fired into rad. Then slow fill until level settles. Works most of the time.
 
wammers said:
Method is to fill header tank right up to the neck initially then when stat opens that excess coolant is fired into rad. Then slow fill until level settles. Works most of the time.
Click to expand...

If changing top hose the one that goes into head and head emptys itself then would head fill up via header tank without starting engine and if not how does thermostat open without enough water in head ??
 
defender300td1 said:
If changing top hose the one that goes into head and head emptys itself then would head fill up via header tank without starting engine and if not how does thermostat open without enough water in head ??
Click to expand...

When you refill the cooling system the head and block fills with coolant, any air in the system goes out through the top hose you changed then through vent pipe on the rad to the header tank to allow the head and block to fill. That is why the vent pipe MUST be clear. So the thermostat has coolant behind it. When engine is run the water pump takes coolant from the block and circulates it via the thermostats bypass valve through the head and heater circuit back to the block. That is why your heater is always hot before the temp gauge rises to normal. That system gives a quick warm up. When the main thermostat opens the bypass valve is closed and sends coolant through the radiator and around the entire cooling system. That is when the coolant you filled the header tank to the brim with flows into the radiator. A slow fill after that until level is reached should do the trick. Then leave to cool for a while and top up to level if needed.
 
wammers said:
When you refill the cooling system the head and block fills with coolant, any air in the system goes out through the top hose you changed then through vent pipe on the rad to the header tank to allow the head and block to fill. That is why the vent pipe MUST be clear. So the thermostat has coolant behind it. When engine is run the water pump takes coolant from the block and circulates it via the thermostats bypass valve through the head and heater circuit back to the block. That is why your heater is always hot before the temp gauge rises to normal. That system gives a quick warm up. When the main thermostat opens the bypass valve is closed and sends coolant through the radiator and around the entire cooling system. That is when the coolant you filled the header tank to the brim with flows into the radiator. A slow fill after that until level is reached should do the trick. Then leave to cool for a while and top up to level if needed.
Click to expand...

Ah a by pass that explains all did not realise there was a bypass, I did notice that the bleed off on the rad has some sort of tiny metal tube that sticks out and can be pushed in towards the rad I had to get a drill bit to pull it out again is this some sort of air cut off when rad is full?? the tube sticks out when you have removed the rubber and attached plastic bleed tube from radiator.
 
defender300td1 said:
Ah a by pass that explains all did not realise there was a bypass, I did notice that the bleed off on the rad has some sort of tiny metal tube that sticks out and can be pushed in towards the rad I had to get a drill bit to pull it out again is this some sort of air cut off when rad is full?? the tube sticks out when you have removed the rubber and attached plastic bleed tube from radiator.
Click to expand...

Normally that would be a plastic tube which is part of the rad top. Maybe someone has broken it and bodged it. You must make sure it is not blocked and it seals properly or you will loose system pressure and maybe boil over under load.
 
wammers said:
Normally that would be a plastic tube which is part of the rad top. Maybe someone has broken it and bodged it. You must make sure it is not blocked and it seals properly or you will loose system pressure and maybe boil over under load.
Click to expand...

Not bodged or broken I fitted it new myself,when you take the bleed hose of the rad the plastic tube that sticks out ( also ) has a metal sliding one within that ill take a photo later for you .
 
defender300td1 said:
Not bodged or broken I fitted it new myself,when you take the bleed hose of the rad the plastic tube that sticks out ( also ) has a metal sliding one within that ill take a photo later for you .
Click to expand...

New one on me i have only ever seen bleed pipe as molded into top of rad.
 
wammers said:
New one on me i have only ever seen bleed pipe as molded into top of rad.
Click to expand...

As you can see a sliding top hat type tube that can be pushed in until it stops without falling inside or pulled out a little more than is already exposed, wierd huh I ain't got a clue thought it might be some sort of stopper pressureised by water what do you think??
6D5BB1D8-2073-454C-B875-106698561FDE-3445-0000043450376F9A_zpsbe909ab8.jpg
 
not seen that before, mine is just a standard moulded pipe outlet onto the top of the rad? Its not an OM rad and I cant see what sort of benefit that has?
How easy would it be to remove it?
 
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