Crankcase Breather Mod TD4

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
I tend to use the fluffy cotton real crankcase filter. I can see the vortex type allowing too much oil into the cylinders at times of low manifold pressure. The M47R uses a stupid direct port breather system. This has to allow more oil mist into the cylinders, than other indirect breather systems.
 
After speaking to a bmw guy he told me very seldom that rubber needs changed and thinks the oil seperater is also
A waiste of time if you change the fibre filter as should be done , another interesting thing is he told me the silicone hoses were for show and if the origanal hoses are keep good they are every bit as good ,
Quote the coloured hoses are cosmetic and used mostly by boy racers.
He said the td4 was one of there best engines when left alone and serviced as it should be ,
He told me I should never remove a working egr as the air intake system was linked to it and the engine was set up to run at its best with the egr operating , he claims if you clean your inlet manifold every 30-40000 MLS the car runs best with egr fitted and working .
 
I tend to use the fluffy cotton real crankcase filter. I can see the vortex type allowing too much oil into the cylinders at times of low manifold pressure. The M47R uses a stupid direct port breather system. This has to allow more oil mist into the cylinders, than other indirect breather systems.

Then more oil more smoke surely.
 
After speaking to a bmw guy he told me very seldom that rubber needs changed and thinks the oil seperater is also
A waiste of time if you change the fibre filter as should be done , another interesting thing is he told me the silicone hoses were for show and if the origanal hoses are keep good they are every bit as good ,
Quote the coloured hoses are cosmetic and used mostly by boy racers.
He said the td4 was one of there best engines when left alone and serviced as it should be ,
He told me I should never remove a working egr as the air intake system was linked to it and the engine was set up to run at its best with the egr operating , he claims if you clean your inlet manifold every 30-40000 MLS the car runs best with egr fitted and working .

I would agree with most of what he has said but the EGR system/design is a 'cop out' where motor manufacturers have created a system that, if not maintained as he describes will eventually kill an engine. I doubt whether any inlet manifolds are cleaned at 40,000-50,000 miles and it must be remembered that all that oil/soot etc enters the inlets on the engine and is supposedly burnt in the cylinders. At the end of the day it's their way of circumventing a problem regards emissions....and when the car is out of warranty they have no obligation to advise or fix it. EGR delete is one way of preventing the continued build up of soot/carbon within the inlet manifold/system...and allowing the engine to live/operate longer.

Manufacturers have moved the goal posts regards inlet systems in the last decade with most going for direct injection. This would mean that nayone buying a petrol Audi/Volkswagen etc etc would be looking at performing a decoke on the had(at the back of the valves) to have the engine operating at maximum efficiency. Manufacturers are just kicking the can down the road until we go electric....

His comment on the hoses may hold some weight, OEM hoses should last a very long time, as to their efficiency they may have slightly better sidewall rigidity' and silicone may 'flare' slightly on higher pressure revs. Whether their effect on engine perfomance is anything to be noted I don't know, only that most perfoance nad tuned race engines use silicone based housework. The cost of buying OEM may be more but I would guess the should last longer than silicone equivilents. From personal experience I fitted kevlar hoses to my old Jag after some rave reviews in a jag Club magazine....biggest waste of money ever(for me anyway) and I would have been better just getting OEM. Asthetically silicone hoses 'rock' and I am no boy racer, just an old fool who bought a freelander (with my eyes fully open, glasses 'on') :)
 
I have egr bypass on mine but waist of time if manifold not cleaned properly,
Took me a week to clean mine , every time you think it's cleaned you get more grunge ,
I steeped mine in oven cleaner for 2 days but even then it took some work.
 
The BMW guy was telling you some truths with a bit of brand loyalty thrown in for good measure.
Silicone hoses last longer and are cheaper than original parts. They are also more able to resist the boost pressure without ballooning. The OE rubber hoses visibly balloon when under boost, even when new. Now hoses swelling slightly under boost doesn't actually affect the boost ratio (pressure), one little bit. However as the turbo begins to boost the intake. Some boost delay is added because the of the ballooning, increasing intake volume slightly. It a small delay, but it's there.

The EGR delete is an interesting argument.
Fitting a delete kit does a couple of things to the engine.
First off it stops any further fouling of the inlet manifold, ports and valves.
Secondly it eliminates the problem of a sticking EGR valve, simply because it's not there to stick.
Thirdly. Removing the EGR improves throttle response, simply because there's no half air, half CO2 in the inlet manifold.

Exhaust gas recirculation was only ever added to the engine to reduce NOX emissions under some operating conditions. The idea is simple. NOX is produced when fuel and air (mostly Nitrogen) are burned at high temperatures. Diesel engines burn fuel at very high temperatures, simply by design.
Adding a non combustible gas (CO2 in exhaust gasses) to the intake, reduces the combustion temperature enough to reduce NOX.
The theory is sound and well proven to work.
However the exhaust gasses from a turbo diesel are far from pure CO2. In fact they contain lots of compounds which aren't helpful to the process. Soot is the main constituent of the exhaust gas. This is what the inlet manifold fills with over time. The sticky component comes from the boosted air charge, in the form of oil. This oil is ejected from the turbo as a fine mist. It combines with the heated soot to make the gloopy tar type stuff that clogs the manifold and inlet tract.
So removing the exhaust gas, keeps the engine running cleaner without having to clean the manifold every few thousand miles.

The BMW version of the M47 was a reliable engine. The M47R (R stands for Rover derivative) is a slightly different beastly altogether. The BMW M47 has a steel crankshaft the "R" 47 has a cheaper forged iron crank. These can and do break on occasion.
The injectors system is also different, the R having a bosch common rail system. BMW 47s used a more conventional sequential electro/ mechanical injection system. This is inherently more reliable than the more complex common rail system.
There are other more minor differences between the different engines, but those are the important ones.

Personally I'm not a fan of anything BMW.
I think the L series could have continued to be a more reliable power unit for the Freelander, right up to its replacement by the FL2.
 
Last edited:
I have egr bypass on mine but waist of time if manifold not cleaned properly,
Took me a week to clean mine , every time you think it's cleaned you get more grunge ,
I steeped mine in oven cleaner for 2 days but even then it took some work.

I have done the same but the EGR delete does, in theory prevent this process from happening...(as in the 'coking up of the inlet side of things)....And I can fully appreciate the 'never ending' work required to clean the manifold...been there and done that...again...and again....and......In reality if you inherit a cr such as this look to clean the inlet at every major service or....buy yourself an new or better inlet manifold...I have looked....'they ain't cheap'!!
 
The BMW guy was telling you some truths with a bit of brand loyalty thrown in for good measure.
Silicone hoses last longer and are cheaper than original parts. They are also more able to resist the boost pressure without ballooning. The OE rubber hoses visibly balloon when under boost, even when new. Now hoses swelling slightly under boost doesn't actually affect the boost ratio (pressure), one little bit. However as the turbo begins to boost the intake. Some boost delay is added because the of the ballooning, increasing intake volume slightly. It a small delay, but it's there.

The EGR delete is an interesting argument.
Fitting a delete kit does a couple of things to the engine.
First off it stops any further fouling of the inlet manifold, ports and valves.
Secondly it eliminates the problem of a sticking EGR valve, simply because it's not there to stick.
Thirdly. Removing the EGR improves throttle response, simply because there's no half air, half CO2 in the inlet manifold.

Exhaust gas recirculation was only ever added to the engine to reduce NOX emissions under some operating conditions. The idea is simple. NOX is produced when fuel and air (mostly Nitrogen) are burned at high temperatures. Diesel engines burn fuel at very high temperatures, simply by design.
Adding a non combustible gas (CO2 in exhaust gasses) to the intake, reduces the combustion temperature enough to reduce NOX.
The theory is sound and well proven to work.
However the exhaust gasses from a turbo diesel are far from pure CO2. In fact they contain lots of compounds which aren't helpful to the process. Soot is the main constituent of the exhaust gas. This is what the inlet manifold fills with over time. The sticky component comes from the boosted air charge, in the form of oil. This oil is ejected from the turbo as a fine mist. It combines with the heated soot to make the gloopy tar type stuff that clogs the manifold and inlet tract.
So removing the exhaust gas, keeps the engine running cleaner without having to clean the manifold every few thousand miles.

The BMW version of the M47 was a reliable engine. The M47R (R stands for Rover derivative) is a slightly different beastly altogether. The BMW M47 has a steel crankshaft the "R" 47 has a cheaper forged iron crank. These can and do break on occasion.
The injectors system is also different, the R having a bosch common rail system. BMW 47s used a more conventional sequential electro/ mechanical injection system. This is inherently more reliable than the more complex common rail system.
There are other more minor differences between the different engines, but those are the important ones.

Personally I'm not a fan of anything BMW.
I think the L series could have continued to be a more reliable power unit for the Freelander, right up to its replacement by the FL2.

I too am not a fan of 'things BMW' but bought this TD4 on the numerous (fake news??? ;-) ) write ups on many sites...including this one.... If I hadn't joined this forum I would be in the darkest of places regards Landy shenanigans and even now I know next to FA!! Just a bit more than FA but not quite enough to start world war 3 or do fatal damage to a TD4(I hope!!) I feel, looking at the complexity of cars and the amount of data controlled systems that the FL1/ TD4/'K' Series/KV6 are probably part of the ultimate generation that the 'home' mechanic etc can truly work on without having to go to a specialist or 'Stealer'. Some may have a different view but when manufacturers have 'Master/Mother' systems needed to programme' their latest creations it just means that us mortals have less opportunity to fix a problem on our driveway/in a green lane somewhere...maybe I am wrong and something will always crop up...(The Law of Evolution etc) but I guess I have a more cynical view of the world today than I did when Mars bars were big and a 'Snickers'(WTAF??) was called a 'Marathon'!!
 
I to have done the mods you guys have done but I didn't change the top of the crank case breather just the cyclone part I have read some were you need to clean the o ring in the right hand side which I didn't do . Will this make a difference ?
 
I to have done the mods you guys have done but I didn't change the top of the crank case breather just the cyclone part I have read some were you need to clean the o ring in the right hand side which I didn't do . Will this make a difference ?

It will be the valve that is part of the crankcase assembly(to the right as you said) of the 'cyclone'/oil separator. If the valve is very dirty(it more than likely will be) it won't work or barely work. I have ordered the hole thing(as in the whole assembly) so I know everything works. I did clean mine in the interim...
 
  • Like
Reactions: tlo
It will be the valve that is part of the crankcase assembly(to the right as you said) of the 'cyclone'/oil separator. If the valve is very dirty(it more than likely will be) it won't work or barely work. I have ordered the hole thing(as in the whole assembly) so I know everything works. I did clean mine in the interim...

What does the rubber valve do and what trouble does it throws up if faulty. does anyone know if you can buy it on its own . Cheers.
 
I would guess that it helps regulate any pressure in the crankcase...it being a crankcase breather. Simple explanation here:

https://en.wikipedia.org/wiki/Crankcase_ventilation_system

I bought a complete 'unit' (Crank case PVC Assembly) as mine had been 'mullah'd by a previous 'enthusiast' who had trashed the allan screws so they were impossible to get off and on(almost). My valve was very dirty, so cleaned it with brake cleaner in the interim. No doubt 'Nodge' will add exactly what issues a 'bad' valve may cause as I am lacking in hard facts regards this(in Freelander terms)
 
The PCV keeps sudden high boost pressure out of the crankcase. Like when the throttle is snapped open briefly.
Under sustained boost. The crankcase pressure equals out with the boost pressure. In this instance, the valve is pulsed open by the pressure waves of the pistons. This bleeds crankcase fumes into the intake to be burned.
 
Then I presume this would not cause a misfire on td4 engine at a certain rpm level as in mine at 2500 rpm.
Taking into account I don't appear to have any pressure worth at dip stick etc.
 
Then I presume this would not cause a misfire on td4 engine at a certain rpm level as in mine at 2500 rpm.
Taking into account I don't appear to have any pressure worth at dip stick etc.
Funny you should say that mine does the same I wonder why
 
Then I presume this would not cause a misfire on td4 engine at a certain rpm level as in mine at 2500 rpm.
Taking into account I don't appear to have any pressure worth at dip stick etc.

A failed or faulty PCV is one potential cause of the 2K misfire. I've a theory that oil drawn from the PCV could contaminate the intake charge at low boost, causing the misfire.
 
  • Like
Reactions: tlo
Funny you should say that mine does the same I wonder why

So does mine. If I hold the revs at 2K. After a few seconds the misfire starts and it makes blue smoke. There's no blue smoke at any other time, except when I hold the throttle at 2K. I did a video of it.
 
  • Like
Reactions: tlo
no blue smoke just the slight misfire about 2.5 k I have some white smoke on start up but that's about it. While there is always the chance the new parts we get could be faulty I have just replaced my pvc there doesn't look like there is much in it to go wrong
 
Back
Top