Coolant Leak Source W212 E250 OM651 ?

pmcgsmurf

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Hi folks

I'm guessing this is coming from the Fuel Filter housing, anyone any thoughts? Leak.jpg
Picture is looking up from underneath and we can see signs of coolant coming from above onto the little silver bracket.

No sign of any leak at the water pump.
 

HITECH

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I just lost all my coolant last night. Checked it today with some die. Its coming out the "freeze plug" which is screwed into the engine as far as I can see. Still trying to source the part. Nobody seems to know anything about them or replacing them. Hopefully thats all your problem is, just a wee gasket or something on one of the parts AND NOT THE HEAD GASGET lol
 

Monkeylegend

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Fuel filter housing is a common issue, as is the water pump. Probably just needs a gasket if it's the fuel filter housing, had it replaced on mine, and as you might have guessed the water pump as well. It did manage 220k before it went though.
 

zipdip

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I just lost all my coolant last night. Checked it today with some die. Its coming out the "freeze plug" which is screwed into the engine as far as I can see. Still trying to source the part. Nobody seems to know anything about them or replacing them. Hopefully thats all your problem is, just a wee gasket or something on one of the parts AND NOT THE HEAD GASGET lol

By freeze plug I take it you mean a core plug,if you ask for one of those you might get what you want,these core plugs are not screwed into the block that would defeat their purpose they are normally gunned in by a air tool,to remove the core plug,you will need to use a sharp tool like a screwdriver and just bash it through and then lever it out,the main problem is being able to insert the new plug,you need to be able to use a suitable drift of the same size as the plug and be able to hit it square,you will need to use some locktite around the edge of the plug just to make certain it stays water tight.
 

brucemillar

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By freeze plug I take it you mean a core plug,if you ask for one of those you might get what you want,these core plugs are not screwed into the block that would defeat their purpose they are normally gunned in by a air tool,to remove the core plug,you will need to use a sharp tool like a screwdriver and just bash it through and then lever it out,the main problem is being able to insert the new plug,you need to be able to use a suitable drift of the same size as the plug and be able to hit it square,you will need to use some locktite around the edge of the plug just to make certain it stays water tight.


Agreed: If it is a "core Plug" they are designed to be pushed out by pressure as the water/coolant starts to freeze to try and avoid the block splitting. I have managed to replace one on aa MKI Cortina.

I had to cut a hole in the firewall to see the plug.
Punch a screwdriver through the plug and use a metal hook to pull it out.
Then using grease I held the new plug onto the end of a hammer shaft, got it as well lined up as I could be eye and thumped the mallet shaft with the flat of my hand.
In it went.

They are interference fit and do not usually have a gasket. The one I did was a just a lead disc, like a large bottle cap.

I suspect it is a dealer only part and cost pennies.
 
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pmcgsmurf

pmcgsmurf

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Fuel filter housing is a common issue, as is the water pump. Probably just needs a gasket if it's the fuel filter housing, had it replaced on mine, and as you might have guessed the water pump as well. It did manage 220k before it went though.

Got a new filter housing and associated parts delivered today, job for next week perhaps, will update when exact cause is known.
 

HITECH

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Im assuming any you have replaced yourself have all been plugged in. For your information IT IS ACTUALLY internally threaded on some engines and screwed into the block as it is in mine. The purpose of them has absolutely nothing to do with being a valve to release pressure. They were put in during the molding of the engines to withdraw any excess sand/washing down after the molding. I have looked into it and used my own qualifications in metallurgy & inspection to understand the point of them. They were given the name freeze plugs by usa / uk ? I have no idea. But yes you are right one technical term for them could be a core plug. Check your books or Autodata and you will see. The replacement I have is also internally threaded to screw into the block with the seal inside it. Thanks for the info anyway but the problem now is replacing it without removing the dpf or exhaust. Its in an extremely awkward place to get to. I reckon I might just reach it with a wobble on an extension. Any info or advice on the access to it would be appreciated.

By freeze plug I take it you mean a core plug,if you ask for one of those you might get what you want,these core plugs are not screwed into the block that would defeat their purpose they are normally gunned in by a air tool,to remove the core plug,you will need to use a sharp tool like a screwdriver and just bash it through and then lever it out,the main problem is being able to insert the new plug,you need to be able to use a suitable drift of the same size as the plug and be able to hit it square,you will need to use some locktite around the edge of the plug just to make certain it stays water tight.
 
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pmcgsmurf

pmcgsmurf

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Got some time today so stripped this down, what a real pain in the backside.

You have to first remove the Vacuum Sensor, then remove the Exhaust Gas Recirculation Cooler.
With these out you then have access to remove the Fuel Filter Housing (with some bendy sockets).

Engine bay looks like this now till after lunch at least.
20180424_121030.jpg

The old filter housing looked like this., note the 2 holes to bolt this on.
20180424_121100.jpg

New one looks like this, 3 holes although we can only use 2.
Thought we had a wrong part at first but guess they have just improved so it does not leak. ;)
20180424_121117.jpg
 
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pmcgsmurf

pmcgsmurf

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All back together, took a couple of hours after lunch.

20180424_154443.jpg

I just need to check coolant level now and take it for a bit of a blast and top up as needed.

Guessing there is no fancy bleeding required.
 
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pmcgsmurf

pmcgsmurf

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Drat, thought this was fixed but it's back to giving a coolant warning again. :(

Will have to see if I can get it pressure tested to see where it's coming from.
 
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pmcgsmurf

pmcgsmurf

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And a pressure test shows no leaks or loss of pressure. :confused:
 

pembssurf

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I’d be very surprised if it was the HG... I’d be looking at everything else possible. Gearbox oil cooler pipe?
 

zipdip

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Wow I thought this was fixed,what bad luck,so you had the pressure test and no visible leaks,I know we had the posts about core plug or threaded plug used for removal of sand when the block is machined,now you said at the time it was coming from that,most blocks have these all they are is a threaded hole with a threaded plug a little like a old male gas plug,many had a square end,they do need a lot of sealant used on them to seal them,with the coolant level dropping and now no visible leak we are now into the realms of a internal engine leak,I hope not,A little off the wall but I take it this car is not driven much?have you checked the heater and it's pipes,have you got a damp carpet.
 

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