Inlet manifold

[Ermir]

Hi guys,
When i recently cleaned my egr on w203, i noticed that the inlet manifold was also very very dirty inside. It looked like it was filled with hot bitumen.
Does it worth to take it out and clean or just leave it as it is, as the car is running perfect? thanks

 

[mersum1es]

Of course you'll get better air flow when manifold is clean, in addition your intake swirl flaps will jam eventually if you let your EGR still functioning.

 

[Lord-WYBMAnE220]

The crud will restrict swirl-flap opening/closing/movement. At idle, they're meant to be shut - but the crud will prevent that - causing poor idling and low-end response (and even dieselling/pinking).
Worst case scenario in BMW engines (not heard of it in Mercs yet) is the swirl-flaps break up, get ingested and destroy pistons, turbos and exhaust boxes.
Get 5-litres of carb cleaner, an empty spray bottle and a toothpick tool to clean it out - it'll come up like new.
If the EGR assembly has to come off, get the assembly to head gasket.

 

[panason1c]

Its a lot of work to remove/refit the inlet manifold and it is likely that the flaps and spindles are already worn (look for oil that has leaked from the spindles and covering the side of the block beneath the manifold) if you are going to remove it, you might as well 'modify' it by removing the flaps and spindles and sealing the spindle holes with bolts. This mod is also carried out by BMW owners.

Plenty of info, do a search on the forum.

 

[Ermir]

Its a lot of work to remove/refit the inlet manifold and it is likely that the flaps and spindles are already worn (look for oil that has leaked from the spindles and covering the side of the block beneath the manifold) if you are going to remove it, you might as well 'modify' it by removing the flaps and spindles and sealing the spindle holes with bolts. This mod is also carried out by BMW owners.

Plenty of info, do a search on the forum.

Yes true, i have noticed signs of oil. Can i buy new flaps or not? how are garages refurbishing them? They told me it need an entire day to clean it.

 

[Ermir]

The crud will restrict swirl-flap opening/closing/movement. At idle, they're meant to be shut - but the crud will prevent that - causing poor idling and low-end response (and even dieselling/pinking).
Worst case scenario in BMW engines (not heard of it in Mercs yet) is the swirl-flaps break up, get ingested and destroy pistons, turbos and exhaust boxes.
Get 5-litres of carb cleaner, an empty spray bottle and a toothpick tool to clean it out - it'll come up like new.
If the EGR assembly has to come off, get the assembly to head gasket.

you mean to clean it in place, without removing?

 

[panason1c]

you mean to clean it in place, without removing?

Attempting to clean it in place would be a pointless task, the crud will extend all the way through the manifold to the point where it meets the cylinder head.......complete access to the crud is impossible without removing the manifold.

If, as you say, you have signs of oil down the side of the block this means the spindles are worn and allowing turbo boost to escape (which also carries 'oil mist' and creates the oil build up on the block) and a new or your own 'modified' manifold is the only option.

I modified one a few weeks ago (a 270cdi) and the result was restored engine performance and absolutely no problems regarding idling, smoke, etc.

Here is a pic of a modified manifold which shows the flap removed and a bolt sealing the spindle hole.

 

[Lord-WYBMAnE220]

Most people say they don't notice a difference after de-flapping.
If there is one, it'll be idle and bottom-end response.
Invest the time to clean it, it's a very worthwhile maintenance item.
Have a look see if the flap spindle seals are leaking oil, with it in place.
If not, just clean it out and off you go again.

 

[Ermir]

Attempting to clean it in place would be a pointless task, the crud will extend all the way through the manifold to the point where it meets the cylinder head.......complete access to the crud is impossible without removing the manifold.

If, as you say, you have signs of oil down the side of the block this means the spindles are worn and allowing turbo boost to escape (which also carries 'oil mist' and creates the oil build up on the block) and a new or your own 'modified' manifold is the only option.

I modified one a few weeks ago (a 270cdi) and the result was restored engine performance and absolutely no problems regarding idling, smoke, etc.

Here is a pic of a modified manifold which shows the flap removed and a bolt sealing the spindle hole.

Thank you. You just gave me the answer of the black smoke!

 

[Lord-WYBMAnE220]

Thank you. You just gave me the answer of the black smoke!

Black smoke can be down to an induction-tract pressure-leak or insufficient cylinder compression for complete combustion. If your glowplugs are oiled, you may have a piston ring (oil-control and compression) issue in one or more cylinders.
Take the pipe off the rocker cover breather pipe and rev the engine - if revving it generates a jet of smoke, you have a blow-by issue that will be feeding oil-mist back into the induction tract and oiling the glowplugs.

 

[Ermir]

Most people say they don't notice a difference after de-flapping.
If there is one, it'll be idle and bottom-end response.
Invest the time to clean it, it's a very worthwhile maintenance item.
Have a look see if the flap spindle seals are leaking oil, with it in place.
If not, just clean it out and off you go again.

Definitely it is not a diy work. I will drive it to the garage to evaluate it.

 

[panason1c]

Definitely it is not a diy work. I will drive it to the garage to evaluate it.

Actually, it can be a diy job, there are no special tools needed, and removal and conversion of the manifold is relatively straightforward, the downside is that it is a very time consuming task.

 

[Lord-WYBMAnE220]

Actually, it can be a diy job, there are no special tools needed, and removal and conversion of the manifold is relatively straightforward, the downside is that it is a very time consuming task.

The man speaks the truth.
It is time consuming - but you won't need speciality tools ... just sufficient patience and perseverence.

 

[Ermir]

Thank you all guys. A last qustion. Can i buy somewhere the flaps and replace them? And can yhe pistons hole be cleaned so i will have all the way through cleaned? Thanks

 

[Lord-WYBMAnE220]

Thank you all guys. A last qustion. Can i buy somewhere the flaps and replace them? And can yhe pistons hole be cleaned so i will have all the way through cleaned? Thanks

If no-one here knows if you can buy flaps on their own (unlikely), your local MB dealership will.
And no, the valve ports can't be safely worked on without removing the cylinder head - and they don't get meaningfully gunked up anyway.
Clean (or get cleaned) the intake manifold and EGR valve.
That will satisfy you and your engine.

 

[mersum1es]

flaps cannot be bought separately AFAIK, dealer offers whole new manifold £££.

 

[Ermir]

How are the garages refurbishing them wihout changin the flaps? Or they jus clean them and thats the refurbishment? They charge 200£ for a ref. one.

 

[Lord-WYBMAnE220]

How are the garages refurbishing them wihout changin the flaps? Or they jus clean them and thats the refurbishment? They charge 200£ for a ref. one.

Replace the spindle oil-seals and clean.
Dunno if the spindle shafts themselves wear much or leak oil when they do - but unless you're doing starship mileage, you're not likely to find out within a year's guarantee.

Anyway, a new manifold's only £220.

 

[simonafloat]

Most people say they don't notice a difference after de-flapping.
If there is one, it'll be idle and bottom-end response.
Invest the time to clean it, it's a very worthwhile maintenance item.
Have a look see if the flap spindle seals are leaking oil, with it in place.
If not, just clean it out and off you go again.

The 270CDI that panason1c was referring to is my ML270 which he worked on. The difference in all-round performance since he cleaned and de-flapped the manifold is pretty amazing.

 

[Buffers]

I did the flap removal conversion on my old 270cdi c class 2-3 years ago. I am no expert, you fairly good diy man. Had trouble free motoring from that point and just sold it on to a friend now how is very happy with it, 200,000 on the clock by the way. I don't think anyone has mentioned that if you do this conversion you will have to replace the step motor that operates the flaps with a resistor so car management system still thinks motor is still there and working. Mersum1es is correct, there is no refurb kit available for inter manifold flap repair. Hope this is helpful and good luck whatever root you take.