What is a catch can?
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scooba_285
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try the search function, i asked this not long ago and got some really in depth explainations, good info
The crank case pressure is released at the rocker cover at the rear of the eng. The tube directs this oil mist/ air to the intake tube just b4 the turbo. Yuk oily air goin into your intercooler etc. The catch can catches it and lets the air now cleaner go on into eng
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It's really just a container that catches the oil being breathed out of your crankcase. Let me explain what happens, and what the bad effect is, then you'll want to buy one.
As the fuel is combusted, some of the gases are forced past your piston rings into the crankcase. This is known as "blow-by". This gas picks up oil mist (hot oil will form a mist) and while some of this is extracted by the oil separator at the top of your engine, not all of it is and the remainder is fed through a tube to the air intake just in front of the turbocharger. It's designed to be combusted by the motor so that it doesn't pollute anywhere.
This is a really, really BAD thing, and here's why.
That oil is going to pass through your intercooler, and it will generally revert to a liquid IN the intercooler. From there, it doesn't move any further. All it's going to do is fill the intercooler.
Grab a catch can and install it, then clean your intercooler.
As the fuel is combusted, some of the gases are forced past your piston rings into the crankcase. This is known as "blow-by". This gas picks up oil mist (hot oil will form a mist) and while some of this is extracted by the oil separator at the top of your engine, not all of it is and the remainder is fed through a tube to the air intake just in front of the turbocharger. It's designed to be combusted by the motor so that it doesn't pollute anywhere.
This is a really, really BAD thing, and here's why.
That oil is going to pass through your intercooler, and it will generally revert to a liquid IN the intercooler. From there, it doesn't move any further. All it's going to do is fill the intercooler.
Grab a catch can and install it, then clean your intercooler.
Bazz
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thanks heaps for the info guys specially your detailed one tony,
makes sense now
, i have a stock zd30 engine i dont believe i have an intercooler, have noticed a small rubber pipe looking from under my engine though that has some oil residue on the end of it all the time.
do you only need it to protect the intercooler?
makes sense now
, i have a stock zd30 engine i dont believe i have an intercooler, have noticed a small rubber pipe looking from under my engine though that has some oil residue on the end of it all the time.do you only need it to protect the intercooler?
Mostly, yes. The gases come from a "Positive Crankcase Ventilation" hose which connects to the top of your motor (almost always at the rear of the camshaft cover on OHC engines, rocker cover on others). If you don't have an intercooler, there's little opportunity for the oil to cool enough before it hits your intake manifold and from there into the engine.
However, a very small amount will stay in the intake manifold and it will build up over time. This will reduce the effectiveness of your intake manifold's flow and will reduce your engine's efficiency.
So it's still a good idea to have a catch can fitted.
Now, about that intercooler ... it serves TWO purposes. The first and obvious one is that it cools down the hot air coming from the turbocharger (when you compress a gas, the gas heats up). The cooler the air, the more molecules of air per cubic centimetre, which means more USABLE air in the combustion chamber = more power, more efficiency.
The second purpose - when the turbocharger destroys itself - as they sometimes do - the intercooler ($1400, I think) saves the engine ($10,000) from certain destruction.
The thing with turbochargers is they need to cool properly before you shut down the motor. Some people fit turbo timers to their cars (illegal) and others fit EGT gauges (Exhaust Gas Temperature) with the probe on the exhaust manifold (the best place for it is right near where the turbo bolts on). When the temperature drops sufficiently, it's safe to turn off the motor.
The heat in the turbocharger tends to burn the oil in bearings, forming hard deposits which eventually build up enough to destroy the bearing. Since the turbine spins at 60,000rpm (trucks) and more (these little ones regularly pass 100,000rpm) then any bearing failure is going to be catastrophic.
That intercooler is not just an efficiency tool, it's insurance. So, fit both!
However, a very small amount will stay in the intake manifold and it will build up over time. This will reduce the effectiveness of your intake manifold's flow and will reduce your engine's efficiency.
So it's still a good idea to have a catch can fitted.
Now, about that intercooler ... it serves TWO purposes. The first and obvious one is that it cools down the hot air coming from the turbocharger (when you compress a gas, the gas heats up). The cooler the air, the more molecules of air per cubic centimetre, which means more USABLE air in the combustion chamber = more power, more efficiency.
The second purpose - when the turbocharger destroys itself - as they sometimes do - the intercooler ($1400, I think) saves the engine ($10,000) from certain destruction.
The thing with turbochargers is they need to cool properly before you shut down the motor. Some people fit turbo timers to their cars (illegal) and others fit EGT gauges (Exhaust Gas Temperature) with the probe on the exhaust manifold (the best place for it is right near where the turbo bolts on). When the temperature drops sufficiently, it's safe to turn off the motor.
The heat in the turbocharger tends to burn the oil in bearings, forming hard deposits which eventually build up enough to destroy the bearing. Since the turbine spins at 60,000rpm (trucks) and more (these little ones regularly pass 100,000rpm) then any bearing failure is going to be catastrophic.
That intercooler is not just an efficiency tool, it's insurance. So, fit both!
the oil won't block up an intercooler all that much. it gets pick up and blown out after a while.
the big problem with engine oil in the intake pipes is that it combines with dust and soot from egr to form the black sludge which blocks up the intake/ports.
also the oil is fuel, its unmetered and can ignite before the main fuel does. so that can cause a few combustion issues.
as you might have noticed the oil also seeps out from all the rubber intake joins. this lubes the joins and can cause them to blow off under high boost.
the big problem with engine oil in the intake pipes is that it combines with dust and soot from egr to form the black sludge which blocks up the intake/ports.
also the oil is fuel, its unmetered and can ignite before the main fuel does. so that can cause a few combustion issues.
as you might have noticed the oil also seeps out from all the rubber intake joins. this lubes the joins and can cause them to blow off under high boost.
Bazz
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hey guys have been thinking about this all day, wether to get the intercooler and if its something that would benefit me for what i want to do, specially with holiday season around the corner and possibly moving......not cheap.
thanks again for all the information its very helpful .
Is the turbo destined to blow on my ute (considering i have a 3" exhaust, snorkel and turbo timer) ? or is it only the odd turbo that goes due bad maintenance and switching engine off when the temp is still high?
I dont need any extra power, i use the ute for the odd job at work and my daily i go 4x4 driving maybe 3-4 times a year at most. I do however want a ute that will last at least 300k comfortably. Is the intercooler a want or a need i guess is what im trying to say?
cheers
thanks again for all the information its very helpful .
Is the turbo destined to blow on my ute (considering i have a 3" exhaust, snorkel and turbo timer) ? or is it only the odd turbo that goes due bad maintenance and switching engine off when the temp is still high?
I dont need any extra power, i use the ute for the odd job at work and my daily i go 4x4 driving maybe 3-4 times a year at most. I do however want a ute that will last at least 300k comfortably. Is the intercooler a want or a need i guess is what im trying to say?
cheers
Your turbo timer is good protection, don't worry too much about the turbo. I wouldn't bust a nut to get the intercooler.
You might (occasionally) want to pop the intake hose off the front of the turbo and make sure the shaft spins smoothly and doesn't wobble - that'll give you peace of mind.
You might (occasionally) want to pop the intake hose off the front of the turbo and make sure the shaft spins smoothly and doesn't wobble - that'll give you peace of mind.
