Oil catch can install

[nxski]

I'm thinking of installing my catch can just above my head. Is this a good position for it? I've heard some say that it should sit below the engine. The reason I've chosen this location is because it's easily accessible, it's the most convenient of the 2 potential spaces in the engine bay, and it's close to the blow by.

[Growlerbearnz]

Hopefully you get some good feedback on this, because that's where mine is going too. It's one of the few spaces large enough for a catch can, and it's close to the existing crankcase breather. I also figure that being up high I can build in a small drain to return the captured oil to the crankcase when the engine is not running.

[nxski]

It was my understanding that the catch can had to sit low so the oil could flow downhill and be caught in the can. If no one answers I'll check back with garage 5 and see what their reasoning was.

[psilosin]

It can be anywhere. The can catches oil vapour. Any minimal oil that settles in the lines to/from will drain to either the can or back to engine...both fine.

[legionnair]

Why a catch can all the big diesels just run a breather straight out to the ground. I did the same just made the line run up to the back fire wall then across to the passenger side and back down along the bell housing.

Only once and a while do I ever leave a drop

[rezdiver]

thats an option but its nice to have positive crankcase ventilation to eliminate seal damage from too much pressure built in the crankcase depending on your engine condition and blowby. also by using the catch can you reduce the amount of oil wasted that can be returned to the sump instead of burnt up through the suction into the intake.

[legionnair]

thats an option but its nice to have positive crankcase ventilation to eliminate seal damage from too much pressure built in the crankcase depending on your engine condition and blowby. also by using the catch can you reduce the amount of oil wasted that can be returned to the sump instead of burnt up through the suction into the intake.

The reason big diesel don't run the crank case vent into the intake is to prevent oil injestion and possible run away. Which I have seen twice at work. The idea of a catch can is not to return the oil but to catch it and allow you to collected it from a drain valve on the bottom off the can. But still allowing the blow by and emission to return to the intake making it emission legal. Which in Vancouver with test centers is a must. The problem with this system is it has to be pre turbo and if you have an intercooler oil collection will accumulate in the intercooler over time if no drain is present or not drained due to lack of knowledge the engine could start sucking the oil and have a runaway which is the death of the engine. Both times it happened at work was from a intake turbo seal leak allowing the intercooler to fill with oil.

I also like to inspect the amount of blow by at cold and hot operation with the aid of a manometer I can deter engine condition base line with out a compression tester ( not as exact) but if it is with in spect then ring condition can be ruled out. Saving me and my customers time and money

[rezdiver]

catch it and drain it or return it, same thing really. if i caught it in the can i would just drain it back into the crank case as that is where it came from.
every VW diesel has the positive ventilation plumbed back preturbo and almost all VW diesels run intercoolers.

if you put in a can and maintain it you eliminate oil in your intercooler and can return it back to the crank or drain it and use it for stirfry.

if you position the catch can so it can drain back in the sump then you have a maintenance free system, if you position it low then you must drain it at regular intervals.

[legionnair]

catch it and drain it or return it, same thing really. if i caught it in the can i would just drain it back into the crank case as that is where it came from.
every VW diesel has the positive ventilation plumbed back preturbo and almost all VW diesels run intercoolers.

if you put in a can and maintain it you eliminate oil in your intercooler and can return it back to the crank or drain it and use it for stirfry.

if you position the catch can so it can drain back in the sump then you have a maintenance free system, if you position it low then you must drain it at regular intervals.

That's fine I am just telling you what I have seen and my experiences/solutions. I have seen an engine run away from oil injestion I will never take that chance. Also positive crancase ventalation is an emission feature brought in the 1970ish the breather pipe method I use will have greater effect going down the road at highway speed from the venturi action of the air passing. Vw had to put breather into the intake by law. If it was a better system then why are all big diesel still using old fashion breathed pipes?

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