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some more info and more pics
Hi guys
Here is my opinion on Oil Catch Cans and why fitting them is a good idea (with provisions)
I wrote this elsewhere so you may see it around.
The common mistake made when buying an Oil Catch Can is that people are fitting units that reduce the size of the breather tubes. For the professional aftermarket parts developer the mantra is to keep to the same design performance as the OEM manufacturer ... OR BETTER.
By keeping to this set of guidelines, upgrading your vehicle with after-market parts will not compromise on safety or reliability.
In this case for Crankcase Ventilation (PCV) Systems keeping to the OEM manufacturer's design rules means having no less an outlet breather tube size than original. Oil catch cans need to be of the same diameter as that of the OEM. There is a reason for this: The manufacturer is concerned with keeping the crankcase free of pressure build up.
Cheap $40.00 oil catch cans from eBay etc with have tiny 10 -12mm inlets/outlets, or fittings acting as reducers, reduce the flow rates of the PCV System thus causing back-pressure in the crankcase. This build-up of pressure causes engine oil to weep from the crankcase seals etc as they were not made to hold pressure.
Pound for pound, diesel engines have more blow-by past the rings than petrol engines and thus flow through the PVC System is higher. We certainly do not want to hold back any pressure here.
I have found one type of Oil Catch Can that fits the bill.
A GOOD CATCH CAN
These specially made Hi Performance ProVent HP200 Oil Catch Can do an excellent job of filtering out the oil from the crankcase gasses that are re-entering the engine through the factory setup … and they do this WITHOUT restricting flow.
In this picture you can see the very large inlet and outlet size. Bigger than any other oil catch can!
INLET/OUTLETS
In my opinion, superior to any other style of Oil Catch Can for another reason, it has 2 relief valves. (most other types have none). One is situated on the inlet side to relieve high pressure, the other on the outlet side to relieve any low pressure. Again, this stops any pressure build up even if the filter becomes blocked from you not cleaning it. Its a great engine safe guard!
RELIEF VALVE
Keeping the oil out of the air intake will benefit in 2 ways
Firstly, oil mist in the air intake entering into the combustion chamber will reduce the octane rating of the combustible fuel. Mainly in petrol engines, this leads to a symptom called "pre-ignition". Pre-ignition is one of the quickest ways to damage cylinder heads, piston crowns and piston rings.
Secondly, (and the main reason) oil entering into the intake manifold combines with the heated gases of the Exhaust Gas Recirculation (EGR) (300-400 deg Cel) and literally bakes to form carbon build-up in the manifold. This carbon build-up, over a relatively short period, restricts the volume of air that would normally be allowed to flow through the manifold into the combustion chamber. (See pictures). The less flow, the less performance. This is well noted on late model Mitsubishi, Toyota and Nissan vehicles.
Partially Blocked Manifold 1
Partially Blocked Manifold 2
Partially Blocked Manifold 3
The first 3 pictures of manifold above were taken of a late model diesel's intake manifolds having 160,000kms on the clock. (3.2 Litre Mitsubishi Paj)
This next pic shows a manifold from a vehicle that had less than 70,000kms on the clock
Partially Blocked Manifold 4
The next one is a pic from a 200 Series Land Cruiser EGR port showing the soot that comes in (along with the 300- 400 deg temps.)
What your engine is breathing from the EGR System
The ProVent HP200 Oil Catch Can has a replaceable element. Maintenance on these is easy too since no actual fittings or pipework is removed to replace / clean filter element.
The last picture shows a CLEANED intake manifold. (same manifold as shown above in the first 3 pics) If you could start with this and add the Oil Catch Can then this would be best.
CLEANED MANIFOLD
Looking at this pic and comparing with the ones above does it look like No 4 cylinder was getting no air at all !!
This is what I am finding in our modern diesels
Hope this helps
Cheers
Hi guys
Here is my opinion on Oil Catch Cans and why fitting them is a good idea (with provisions)
I wrote this elsewhere so you may see it around.
The common mistake made when buying an Oil Catch Can is that people are fitting units that reduce the size of the breather tubes. For the professional aftermarket parts developer the mantra is to keep to the same design performance as the OEM manufacturer ... OR BETTER.
By keeping to this set of guidelines, upgrading your vehicle with after-market parts will not compromise on safety or reliability.
In this case for Crankcase Ventilation (PCV) Systems keeping to the OEM manufacturer's design rules means having no less an outlet breather tube size than original. Oil catch cans need to be of the same diameter as that of the OEM. There is a reason for this: The manufacturer is concerned with keeping the crankcase free of pressure build up.
Cheap $40.00 oil catch cans from eBay etc with have tiny 10 -12mm inlets/outlets, or fittings acting as reducers, reduce the flow rates of the PCV System thus causing back-pressure in the crankcase. This build-up of pressure causes engine oil to weep from the crankcase seals etc as they were not made to hold pressure.
Pound for pound, diesel engines have more blow-by past the rings than petrol engines and thus flow through the PVC System is higher. We certainly do not want to hold back any pressure here.
I have found one type of Oil Catch Can that fits the bill.
A GOOD CATCH CAN
These specially made Hi Performance ProVent HP200 Oil Catch Can do an excellent job of filtering out the oil from the crankcase gasses that are re-entering the engine through the factory setup … and they do this WITHOUT restricting flow.
In this picture you can see the very large inlet and outlet size. Bigger than any other oil catch can!
INLET/OUTLETS
In my opinion, superior to any other style of Oil Catch Can for another reason, it has 2 relief valves. (most other types have none). One is situated on the inlet side to relieve high pressure, the other on the outlet side to relieve any low pressure. Again, this stops any pressure build up even if the filter becomes blocked from you not cleaning it. Its a great engine safe guard!
RELIEF VALVE
Keeping the oil out of the air intake will benefit in 2 ways
Firstly, oil mist in the air intake entering into the combustion chamber will reduce the octane rating of the combustible fuel. Mainly in petrol engines, this leads to a symptom called "pre-ignition". Pre-ignition is one of the quickest ways to damage cylinder heads, piston crowns and piston rings.
Secondly, (and the main reason) oil entering into the intake manifold combines with the heated gases of the Exhaust Gas Recirculation (EGR) (300-400 deg Cel) and literally bakes to form carbon build-up in the manifold. This carbon build-up, over a relatively short period, restricts the volume of air that would normally be allowed to flow through the manifold into the combustion chamber. (See pictures). The less flow, the less performance. This is well noted on late model Mitsubishi, Toyota and Nissan vehicles.
Partially Blocked Manifold 1
Partially Blocked Manifold 2
Partially Blocked Manifold 3
The first 3 pictures of manifold above were taken of a late model diesel's intake manifolds having 160,000kms on the clock. (3.2 Litre Mitsubishi Paj)
This next pic shows a manifold from a vehicle that had less than 70,000kms on the clock
Partially Blocked Manifold 4
The next one is a pic from a 200 Series Land Cruiser EGR port showing the soot that comes in (along with the 300- 400 deg temps.)
What your engine is breathing from the EGR System
The ProVent HP200 Oil Catch Can has a replaceable element. Maintenance on these is easy too since no actual fittings or pipework is removed to replace / clean filter element.
The last picture shows a CLEANED intake manifold. (same manifold as shown above in the first 3 pics) If you could start with this and add the Oil Catch Can then this would be best.
CLEANED MANIFOLD
Looking at this pic and comparing with the ones above does it look like No 4 cylinder was getting no air at all !!
This is what I am finding in our modern diesels
Hope this helps
Cheers
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