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Discussion Starter #1
Hi,
Have just changed my thermo,coolant pump and now cannot get the airlock out of the coolant system.
Front of car raised, top hose hot, bottom hose cold, heaters cold, does not over heat stood stationery ( have not driven the car )
It says in the coolant bleeding threadthat top up until no more air bubbles come out of bleed screws, have done this and you cannot get anymore water into expansion tank and still the airlock persists..any surgestiuons would be helpful. :frown
Webber
 

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Hi mate. I did mine yesterday. I had mine running from cold with both bleed screws open and the cap off. heater on full heat but 3 bars on the power. As the engine sucked the coolant through i added little by little, replacing the screws then the cap once it had filled to where it should. I had a small air lock still so when the car was hot i undid the bleed screw next to the rad cap slightly and let it hiss steam/air for a few seconds then tightened it then just to make sure once it had cooled down i parked it on a curb (cold) with the engine off and just squeezed both pipes (upper & lower) until the water level raised and lowered whilst squeezing the pipes seperatly for about ten mins. This pushes all the air to the top. Mine is fine now. Hope this helps

Ben.
 

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If the first method isn't working then try the 2nd listed here.

How to bleed the cooling system.
1.Jack the front of the vehicle up onto stands as high as possible,
2.Turn the ignition on to Aux 2, Engine OFF, heater on fan setting 1 and temperature fully hot,
3.Remove the rad cap/expansion cap,remove the bleed screw from the radiator and IF you have them the bleed screw(s) from the thermostat housing/top hose, return pipe or EGR thermostat.
4.Fill the radiator/expansion tank up and keep pouring till there are no more air bubbles coming out from the bleeds, using a funnel that fits tight in the expansion tank neck and filling it full of water will help push any troublesome air out, when good you can then install the bleeds and tighten down(don't snap them),ensure the rubber O-rings/seals are still on the screws/on the bleed holes.
5.Suck some water out so it's not full to the brim, start the car up and check coolant shoots out of the small hole on the inside of the expansion tank neck when the revs are held up, if it does then replace the cap and then run the car up and check for heat from the vents when the car is warm, then carry on and check if over heating still persists. You may have to bleed troublesome cars again afterwards.(but very rare).
6.If all is good then check the water level again in the morning when cool.

or

Ignition on, heater set to hot, bleed screw out.
Pull the top hose off the radiator. Pour coolant SLOWLY down the rad hose a litre at a time. When the coolant is building up in the hose, hold it above the level of the rad hose stub and keep adding it. When coolant starts to dribble from the rad, refit the hose. You may find that coolant starts to overflow from the rad cap orifice - if it does, just screw the cap back on. Once you've done that, the engine and radiator are full of coolant - the little air pockets that might be left will come through the bleed screw.

After the vehicle is bled you should check that when the revs are held up you get a flow of coolant shooting out of the hole in the inside of the expansion tank neck, this will help tell you if the water pump is circulating, then run the car up and check the lower radiator hose gets hot.
 

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Discussion Starter #4 (Edited)
Hi,
Thanks for the advice. Have done the things you have said..think iam getting somewhere now...getting heat inside the car but only on the passenger side, should i just carry on with the bleed screws ???
Engine not over heating so could i continue bleeding over the next few days ?
Thanks Webber
 

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Sod all that!!
Mine bled perfectly well with a hose pipe and a rag wrapped round it as you fill with the bleed screws open. None of this raising the front end stuff. force of the water gets rid of all the air.
 

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There is a very small bore pipe that goes to the expansion tank, the car will never bleed if this is blocked. The pipe itself doesn't normally block but the bit on the tank or on the rad where the pipe fits often does. Worth a try? Poke a piece of wire through the pipe stubs and check you can blow through it when done.
 

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More details as requested: Drain coolant ,add anti freeze, open bleed screw, place hose with rag around filler neck, turn tap on and use water pressure to force air from system, rag seals the filler neck. 5 mins and done. No need to raise front end etc etc, just simple physics.
 

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More details as requested: Drain coolant ,add anti freeze, open bleed screw, place hose with rag around filler neck, turn tap on and use water pressure to force air from system, rag seals the filler neck. 5 mins and done. No need to raise front end etc etc, just simple physics.
isn't tap water not recommended ? I thought distilled was the way to go !
 

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More details as requested: Drain coolant ,add anti freeze, open bleed screw, place hose with rag around filler neck, turn tap on and use water pressure to force air from system, rag seals the filler neck. 5 mins and done. No need to raise front end etc etc, just simple physics.
But this will only work in some cases, like if there are no pockets inside the cooling system where air can get trapped.

Think of it like a sinking boat or a bottle in a bath, you always have a air pocket at the top, and it's not until the bottle is tilted that the air dispels, even though water is rushing in under pressure. :thumbsup

It all helps, :)
 

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Discussion Starter #14
Hi all,
Thanks for all the helpful posts.
Left the car overnight raised at the front, first thing this morning squeezed both top - bottom hoses, had a good ride out and thankfully everything seems ok, heat coming through and needle dead centre on gauge...pheeeeeeew. Will still keep an eye on it the next few days but hopefully should be ok. :thumbsup
 

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Hi all,
Thanks for all the helpful posts.
Left the car overnight raised at the front, first thing this morning squeezed both top - bottom hoses, had a good ride out and thankfully everything seems ok, heat coming through and needle dead centre on gauge...pheeeeeeew. Will still keep an eye on it the next few days but hopefully should be ok. :thumbsup
:thumbsup told you so. Hope it stays like that for you! mate
 
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