Catch can

Yes there is!!!! it could state a little time to explain, so having a diesel turbo motor, the turbo blows air into the intake manifold at pressures of around 12 psi, some like mine get up to 15 psi (with out any problems). What happens is the "sucking" of the air from the air filter can cause oil being sucked from the blow by pipe. Which comes out of the rocker cover (on most TDs) and goes into the intake pipe between the air filter and the turbo in let. This is why oil is noticed in the intercooler, and if this build up to much you can loose boost pressure. And I believe this is a major reason for the Nissan 3.0 Lt problem.
I first noticed this problem after fitting my snorkel and putting an oil based filter in the snorkel as well as having one in the air box. I now do not use any other filter but paper ones. Mine was that bad oil was leaking out of the turbo, turbo was ok. All for now cheers

Mate,
the main reason for fitting a catch can to a modern diesel is to stop the oil going back into the engine to be burnt, this oil lines the piping and and can cause problems with sensors and turbo. The egr valves also pump some horrible crap back into the engine.

Have a good one

G'day, yes there is. A catch can will intercept any oil from your PCV to the suction side of the turbo and hence the intercooler. It is quite common when you inspect your intercooler, to find oil contaminating it and lessening the cooling function. A catch can "catches" the oil and allows you to drain it away. Most catch cans sold do not work, they have an inlet and outlet at the top and don't allow for any oil to dropout. Easily fixed, needs a seperator of some sort, to make the air/oil path longer and s/s mesh packed into the can.(S/S saucepan cleaning pads) Hope that is easy to follow? John

I agree with the other respondents.... but would just add that the most professional catch can I know of (and use on my 6.5 Chev V8 diesel), is the Provent 200.
Provent 200

carlj.
The most important function of the catch can is to protect the MAF from contamination, a contaminated MAF can cause over boost or incorrect injection.
Eric

Two further reasons for fitting catch cans, albeit usually on more modified engines, is to stop oil getting into the turbo, being heated and fed under pressure into the engine creating a further fuel source. This excess fuel will cause higher engine revs which forces more oil in which increases revs which forces more oil in... i think you get the picture.. Higher boost usually causes greater crank case pressure exasperating the problem. You simply wont be able to shut the engine down as it's creating it's own fuel source.
Secondly, a droplet of oil hitting a turbo wheel at 38,000rpm will knock a blade or two off without hesitation..

Dan

Well ya learn something new everyday.

Excuse the dopeyness, but where does one mount one of these catch cans?

Sounds like they are cheap insurance.

Gday...

Well, well, well - I learn something new every day.

I have only had two turbo-diesel vehicles - Hyundai Terracan CRDi Auto and now a Discovery 3 TDV6 Auto.

No-one has ever mentioned the need for an "oil can" for these, although I have never heard them mentioned anywhere previously for that matter.

Are these "oil cans" mainly for the Toyota/Nissan variants? (My son has a 2000 HiLux 3ltr turbo-diesel manual) - and if the need is so desparately imperative, how come the manufactuers are not fitting them to their vehicles as standard.

I am constantly learning from these forums.

cheers

Julie & John

Just emptied mine on my 2000 Courier TD and after about 8500km I emptied about 25-30mls of oil that would have ended up in the intercooler. My old intercooler pre catch can was full of oil. I think it's a cheap, easy addition to do yourself.