OM651 Coolant into Intercooler. 2014 Viano

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m80

MB Enthusiast
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Apr 26, 2015
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Location
Derbyshire, High Peak
Car
Viano ex long, 651 2014. S211 646 2009 (till the Gov't drones blow 'em off the road)
2 issues,
one is sweet smelling white smoke when engine cold, goes away above perhaps 30 degrees.
Another is a puff of black smoke when stationary and engine revved.

I've stripped a fair bit out of the Viano. In truth I'm learning this congested, complicated engine as I go.

Removing intercooler there was a fair amount of coolant within.
EGR cooler not at fault as dry on the exhaust faces.
I see from youtube the fuel filter housing isn't likely to be the culprit, as the common leak there results in a wet inlet manifold below, that looks dry.

Thoughts appreciated.
 
2 issues,
one is sweet smelling white smoke when engine cold, goes away above perhaps 30 degrees.
Another is a puff of black smoke when stationary and engine revved.

I've stripped a fair bit out of the Viano. In truth I'm learning this congested, complicated engine as I go.

Removing intercooler there was a fair amount of coolant within.
EGR cooler not at fault as dry on the exhaust faces.
I see from youtube the fuel filter housing isn't likely to be the culprit, as the common leak there results in a wet inlet manifold below, that looks dry.

Thoughts appreciated.
Not sure if this helps, but some of these engines have a separate cooling system for the charge air as in a 'charge air cooler'. I don't know about the Viano, but in the current C and E classes with the 651 engine, there is a separate reservoir in the engine compartment for this purpose and there have been a couple of incidences on here where these have leaked. This might be worth investigating further.

Ernie
 
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Not sure if this helps, but some of these engines have a separate cooling system for the charge air as in a 'charge air cooler'. I don't know about the Viano, but in the current C and E classes with the 651 engine, there is a separate reservoir in the engine compartment for this purpose and there have been a couple of incidences on here where these have leaked. This might be worth investigating further.

Ernie
So I guess that would be cooling the intake air as does the intercooler.
I'm sure I don't have the additional reservoir you mention so don't believe this applies to mine.

Thanks though all suggestions appreciated.
 
A while ago I replaced the thermostat. Genuine from MB Newcastle.

I've dug out the old one and can see the underside port is dry, unlike the rest that is still with moisture.

I remember the underside port sits on a plastic loose tube, as I almost missed it on rebuild.

Is this into the air tract ?

If this is to the air intake route and leaking it could explain the pooling of coolant in the intercooler while the engine is off.
 
The lower port looks to me to be into the water jacket on the block.

Any one with suggestions where the coolant can be finding its way into the air route?
Then to settle at he lower intercooler.
 
I'm in a busy time with business pressure so haven't done much to this, so the Viano sits waiting for an answer. In fact I've been considering an estate to get me through.

Anyone any thoughts as to how water finds its way to sit within the intercooler on the 651?
 

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