Bleeding the cooling system

mercmadjim

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I have just fitted a new water pump to my 300TE :), and in the morning I am going to put coolant in.
However I notice in the top of the thermostat housing there is a bleed screw, so I am guessing there is a procedure to follow.

Do I turn the heater control to hot ? as on some of the other cars I have done, will it self bleed?
All advice greatfully recieved.:)
 

keith100

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Hi Jim

This is what I do

1 fill rad
2 check overflow tank level is at least filled to "cold" mark
3 set heater on Max
4 start motor
5 add more coolant until it won't take any more
6 idle the motor until thermostat opens
7 watch rad until air bubbles enter the top of the rad
8 add coolant until level is stable and bubbles cease
9 tighten rad cap

Oh.... and make sure you closed any drain cocks before you add the coolant....learnt that the hard way:lol:

HTH

Keith
 

Blakey

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The odd squeeze on the bottom hose will help move any air out. :)
 

television

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Yes heater on hot, as Blakey, squeezing the bottom hose works wonders
 
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mercmadjim

mercmadjim

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Thank you very much gentlemen, I hope it's going to be smiles alround later.
 

Smudge

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This engine can be a b**er to bleed air out off.
Your right, the top of the stat housing is a bleed screw but more importantly there are others in the head which need to be bled too. It's likely you will get an air lock in the head otherwise. This will lead to severe overheating if not done. Not sure now where the screws in the head are as my memory is not what it was.But if you have a Haynes manual it may show them in there. Or the Russian site may have exploded view of head.
 

television

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This engine can be a b**er to bleed air out off.
Your right, the top of the stat housing is a bleed screw but more importantly there are others in the head which need to be bled too. It's likely you will get an air lock in the head otherwise. This will lead to severe overheating if not done. Not sure now where the screws in the head are as my memory is not what it was.But if you have a Haynes manual it may show them in there. Or the Russian site may have exploded view of head.

When the water pump leaked on my 300TE there was never a problem filling it. there are no bleed screws to my knowledge
 

Smudge

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Not wishing to contradict you Malcolm , but I had a real problem with getting air out of mine. Stuck a hose pipe on it in the end to blow air out.
 

television

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Not wishing to contradict you Malcolm , but I had a real problem with getting air out of mine. Stuck a hose pipe on it in the end to blow air out.

Fair comment ;):D
 
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mercmadjim

mercmadjim

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Yet again, thanks to the good people of this forum, and Television (Malcolm) with his wisdom and papers, I have saved a lot of money and fitted a water pump and bled the system on my 300TE, thank you to all people who contributed on this post and my other post http://forums.mercedesclub.org.uk/showthread.php?t=48881

Big smiles alround!!:):):):)
 

Burtie1967

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Cooling system airlock

Anybody know the procedure for bleeding air out of cooling system on
Mercedes e220 cdi classic it's the 2151cc diesel on a 51- plate
 

television

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Anybody know the procedure for bleeding air out of cooling system on
Mercedes e220 cdi classic it's the 2151cc diesel on a 51- plate

There is nothing other than what is in this post, just do it the same way :D
 

mattuk

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I never been bleeding on mercedes but i was doing in bmw. The warst is to get aor from matrix heater as this is the highest point in cooling system.
How high is is in mercedes?
 

television

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We never get problems in the heater matrix as the flow is reversed to normal
 

Burtie1967

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Tried this but sons think I'm having any luck when I squeeze top hose it's as though I can't feel any water in it bot there was before I took inlet manifold off to modify
 

television

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Tried this but sons think I'm having any luck when I squeeze top hose it's as though I can't feel any water in it bot there was before I took inlet manifold off to modify

Please get the car up to temp thats 85c, then turn the engine off, remove the filling cap taking care not to let the water out or scold yourself, so turn it slowly to release the pressure then squeeze the bottom hose, this will send any air out, sure give the top hose a couple
 
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