Om651 egr cooler leak

[Alexetto72]

Hi
my C250cdi smokes white from exhaust in col starts. in addition to consuming coolant
I had already changed the water pump, thermostat and oil filter housing.
my mechanic bypassed the egr cooler He connected the two coolant hoses connected to it.
Now I have no more coolant loss
Do we have to change the egr cooler or just the metallic seal A6511422480 ?
Thank you

 

[m80]

I pressurised mine to 30 psi with a little water in it. It held.
Rebuilt it has a some sweet smelling white smoke at start up.

My diagnosis is that the cooler is passing within when warm. It then allows some coolant to find its way into the intake tract as it cools.
That coolant is sucked through the engine at start up.

I'm aiming to replace the whole cooler that is held by 6 bolts to the EGR.

 

[Alexetto72]

Thanks M80

 

[Alexetto72]

Thanks M80

I pressurised mine to 30 psi with a little water in it. It held.
Rebuilt it has a some sweet smelling white smoke at start up.

My diagnosis is that the cooler is passing within when warm. It then allows some coolant to find its way into the intake tract as it cools.
That coolant is sucked through the engine at start up.

I'm aiming to replace the whole cooler that is held by 6 bolts to the EGR.

So I will replace the heat exchanger (item10)
What about the bypass valve (item300)
My opinion is that could also leak coolant into intake through the recirculating pipe?

 

[m80]

I suppose it could be passing at 300 or 10.
As the cooling matrix within 10 is just a radiator design I viewed it to be most likely there.

If your mechy has bypassed 10 (assumed) then surely that points to that as the issue.

Where our symptoms might well vary is that we are seeing temperatures at freezing now, so with that is increased condensation within the various components and white smoke at start up. You are I assume (again) might be feeling it a bit cool at what I experience as summer temperatures.

Anyway for me 1st is the cooler, then think again if that hasn't solved mine. But I'm not in a rush, my coolant is constant level and a bit of white smoke isn't a great worry.

 

[Alexetto72]

I suppose it could be passing at 300 or 10.
As the cooling matrix within 10 is just a radiator design I viewed it to be most likely there.

If your mechy has bypassed 10 (assumed) then surely that points to that as the issue.

Where our symptoms might well vary is that we are seeing temperatures at freezing now, so with that is increased condensation within the various components and white smoke at start up. You are I assume (again) might be feeling it a bit cool at what I experience as summer temperatures.

Anyway for me 1st is the cooler, then think again if that hasn't solved mine. But I'm not in a rush, my coolant is constant level and a bit of white smoke isn't a great worry.

No more coolant loss after I changed the gasket a6511420281. Very happy. Didn’t open hood since that
I was trying to source this leak since I bought this car 3 years
Changed coolant pump(was leaking)
Oil filter housing upper hose and radiator was leaking too
But coolant loss remained
really a shame that I only found the source of the leak when I had to part with this car

 

[m80]

No more coolant loss after I changed the gasket a6511420281. Very happy. Didn’t open hood since that
I was trying to source this leak since I bought this car 3 years
Changed coolant pump(was leaking)
Oil filter housing upper hose and radiator was leaking too
But coolant loss remained
really a shame that I only found the source of the leak when I had to part with this car

Is that gasket this?

Pardon our interruption...

 

[Alexetto72]

Is that gasket this?

http://[URL]https://www.ebay.co.uk/itm/131369279814?hash=item1e96382146:g:E8YAAOSwAL9UgId

-[/URL]

Yes

Is that gasket this?

Pardon our interruption...

yes. 2 bolts broke to remove the upper part of the egr

 

[balderdash]

View attachment 121534
So I will replace the heat exchanger (item10)
What about the bypass valve (item300)
My opinion is that could also leak coolant into intake through the recirculating pipe?
View attachment 121535

High I have the same problem I buypased the egr cooler the smoke disappeared when engine warmed up, but when started up next day white smoke when warmed up, (no water in cooler still buypased), checked for head gasket .no gas. Thinking the o ring as stated manifold, can it be changed from the top without disconecting the manifold at the dack of the engine cheers atb.