Crank Breather

Morning everyone!

I have a topic I thought I'd bring here just to see what your thoughts are.
Question: Does diverting the breather from the intake to atmosphere damage the Turbo?

I've put the question in short above ^^^ for those of you who don't want to read, but here is my explanation.
When my Turbo went 2 days ago, the AA recovery bloke saw my diverted rocker breaher and said that was the cause because that lubricates the Turbo. To which I replied, "That's what the oil lines to it are for" he didn't like that and said the breather has oil vaper from it that lubricates the buts the oil can't get.

To me that's rubbish, I work with machines that have all of their breathers vented outside, and also there are plenty of newer engines that have no breathers vented into the intake. They do it nowadays for the emisions to reburn the oil vaper... Right?

To be any vaper that goes into that Turbo will be burnt before it can do any lubricating.

So what are your thoughts on this? Have I and many other people including manufacturers been wrong all these years and this bloke is right or is he talking rubbish?

I'm hoping this will be a good interesting thread!

Hi, IMO it's not about lubrication but about crankcase depression controll cos the DCV(depression control valve) which is connected to the intake with the breather hose reacts to the vacuum created in the intake by the sucction at high revs and closes as to limit the depression in the cranckase, that's why the quality vent systems(Pro-vent or similar) have theyr own DCV ...it has a certain effect on fuelling at low revs too cos the air flow through the MAF is lower when the valve is opened as part of that flow is coming from the crankcase not all from the air intake...

to your question: "Does diverting the breather from the intake to atmosphere damage the Turbo? " i'd say not really but it's not a good move either cos excessive crankcase depression is not good for the engine and it increases oil consumption too

sierrafery said:

Hi, IMO it's not about lubrication but about crankcase depression controll cos the DCV(depression control valve) which is connected to the intake with the breather hose reacts to the vacuum created in the intake by the sucction at high revs and closes as to limit the depression in the cranckase, that's why the quality vent systems(Pro-vent or similar) have theyr own DCV ...it has a certain effect on fuelling at low revs too cos the air flow through the MAF is lower when the valve is opened as part of that flow is coming from the crankcase not all from the air intake...

to your question: "Does diverting the breather from the intake to atmosphere damage the Turbo? " i'd say not really but it's not a good move either cos excessive crankcase depression is not good for the engine and it increases oil consumption too

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Hey,
I didn't know it had an effect on the fueling, I can't say I noticed a difference if I'm honest.
For as long as I've been around engines when I went a long with my father on the farm all of the breathers on the tractors were all just vented down to the ground so on all of my past cars and current ones I've done exactly that. Two of them had oil catch tanks on the breathers but mostly just a pipe down to the ground. The same with this TD5.
I'm hoping to learn something here so keep the posts coming please.
I've always been taught an engine must be able to breathe and the better it can breathe the better it'll work. I assume these newer engines aren't like the older ones...

RustySkull said:

all of the breathers on the tractors were all just vented down to the ground so on all of my past cars and current ones I've done exactly that. Two of them had oil catch tanks on the breathers but mostly just a pipe down to the ground. The same with this TD5.

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Hmmm... a good start would be to not compare a turbo diesel EUI/PD engine with complex electronic management with a naturally aspirated tractor engine though , so even if you dont notice a difference better not drive the Td5 much like that cos it's not healthy for the engine

sierrafery said:

Hmmm... a good start would be to not compare a turbo diesel EUI/PD engine with complex electronic management with a naturally aspirated tractor engine though

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Haha, they're TW30's and 25's for example, they're Turbo'd.

Anyway, I've done many miles on the TD5 like this, over 6 years of trips across the country and local driving also.
Anyway like I said I'm hoping to learn something as well as hear your thoughts on the original AA blokes claim lol.

In my history never ever trust what the AA/RAC/Recovery fella says. Some of them know their stuff but the majority know fu ckall.

I once broke down in my 90 due to a very bad earth causing an electrical failure, the recovery fella told me its because I got water in my turbo

Another told me my diff went because I fitted alloys instead of the LR steel wheels

As per your question, I've got a Provent and the original DCV (not sure I actually need this anymore?) fitted, picks up a fair bit of oil blow by which normally would be chucked into the intercooler/inlet

bankz5152 said:

In my history never ever trust what the AA/RAC/Recovery fella says. Some of them know their stuff but the majority know fu ckall.

I once broke down in my 90 due to a very bad earth causing an electrical failure, the recovery fella told me its because I got water in my turbo

Another told me my diff went because I fitted alloys instead of the LR steel wheels

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Haha I agree I'm glad I'm not the only one who thinks they don't know much.

bankz5152 said:

As per your question, I've got a Provent and the original DCV (not sure I actually need this anymore?) fitted, picks up a fair bit of oil blow by which normally would be chucked into tcooler/inlet

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I agree, I like to take the breathers off to avoid it all going back into the engine... I think of an engine like a Human, the cleaner the air the better it'll run...

RustySkull said:

Anyway, I've done many miles on the TD5 like this, over 6 years of trips across the country and local driving also.

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That still doesnt mean it's good for the engine to have no crankcase depression control

sierrafery said:

That still doesnt mean it's good for the engine to have no crankcase depression control

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Yeah I agree I'm hoping no damage has been done because of this.
I'm hopng the lack of power over the last few months has been due to the Turbo starting to fail.