Coolant O ring w212 top rad hose

[Lingwood]

Since changing my o rings for the turbo outlet by coincidence I have been loosing some coolant and twice had the message on the dash

No visible leaks and no oil or water visible contamination

I have also changed the coolant cap and still loosing

My next check is the hose or more specifically the O ri g for the top radiator hose exit the thermostat body as in removing the turbo pipe I think I was forcing this hose a bit?

Just checked it now and coolant level
Is down about 1/4 inch and the top hose is sucked in.

Anyone know part number for that O ring or got a drawing showing parts?

It is for a w212 2010 e class

Thanks

 

[Steve@Avantgarde]

The top hoses go porous on the alloy crimp and leak. Seen quite a few, if you look underneath where it connects into the radiator you will usually see the tell tale signs. Do check the water pump (originals were plastic, now modified with aluminium pumps) and also the fuel filter housing.

Some 651's leak more water than the titanic.

 

[Lingwood]

I think mine is a 642?

I can see no sign of coolant leak but will check again

I have had a price for both seals of £9 or full hose of £25, probably best to do the hose?

It’s a bit hard to see the water pump? But wouldn’t I see some leakage lower down?

Also not sure what you mean about the fuel filter? Is there a water connection?

 

[Steve@Avantgarde]

So it is, my mistake, I thought it was a E250CDI, in which case ignore all of the above except replacing the hose!

Once you have replaced that hose I would recommend you have a pressure test of the cooling system done, then you will see if you have a leak or not.

 

[Lingwood]

Thanks, I think given your comments about the crimp going I would be daft to only replace the seals for the extra £15 of full hose?

Looking at the simplest:easiestbvious reasons for leak given what you said and that I know I have moved and disturbed that hose getting out the turbo exit I am sure this hose is reason
For my coolant loss

 

[Lingwood]

So I have found the leak and it want the hose! Good job I did not buy one.

Leak is at back of engine under turbo. Possibly egr gasket?