Side-issue to the catch-can debate - how do you 'clean' a diesel motor head without one capturing blow-by vapours?

[sunrk]

So my 80's 1hz is the original motor ex factory - original head and all to the best of my knowledge. Never been off the block in the 12 years I've owned the vehicle. One of the exhaust stud mounts is cracked off, I've done the shims once, and not much else.

If feeding the blow-by gases back to the intake is such a bad thing, how do you sort out oil/carbon deposits accumulating in the intake and does a 1hz have a prevelance for that to actually occur?

Should I even be bothered or care? How would I tell if it's affecting the engine performance/behaviour in any way?

 

[duncanrm]

If feeding the blow-by gases back to the intake is such a bad thing, how do you sort out oil/carbon deposits accumulating in the intake and does a 1hz have a prevelance for that to actually occur?

Should I even be bothered or care? How would I tell if it's affecting the engine performance/behaviour in any way?

They dont really accumulate to a problematic level because they arent mixing with soot from EGR. I recently cleaned out a 2H intake manifold that had done maybe 600,000klms without coming off the engine - it was oily and nasty, almost greasy but it was entirely serviceable and the deposits would in no way have impacted the performance of the engine.

 

[chapel gate]

with out EGR the cross over pipe and inlet manifold stay clean with a slight oil film.

tends to sit on the back of the intake valves with just the PCV connected.

 

[mudgudgeon]

Your 1HZ has survive 700kkm without a catch can. I'd wager it'll survive a few more K's

Of the millions of engines built each month, almost zero will ever see a catch can

 

[sunrk]

Not going to fit one to mine, but just commenting on the 'trend'. They're very heavily promoted by the aftermarket 4wd industry here similar to how ARB/TJM push stuff that most people with 4wd's don't actually need.

 

[ATL Cruiser]

They dont really accumulate to a problematic level because they arent mixing with soot from EGR. I recently cleaned out a 2H intake manifold that had done maybe 600,000klms without coming off the engine - it was oily and nasty, almost greasy but it was entirely serviceable and the deposits would in no way have impacted the performance of the engine.

This is absolutely 100% correct.

I drove a TDI for the last 22 years straight. Same car. 260k miles.

After 100k miles of EGR, the intake looked like this:

After cleaning it with a blow torch, I disabled EGR in the computer. I didn't delete it. I just disabled it. Same intake, same PCV system, just no EGR. After another 160k miles on it, the intake is still crystal clean from the first cleaning.

It's the EGR that clogs it, not the crankcase vapors.

 

[sunrk]

Eww EGR.

 

[MUDZLLA]

This is absolutely 100% correct.

I drove a TDI for the last 22 years straight. Same car. 260k miles.

After 100k miles of EGR, the intake looked like this:

How do you soft-disable the EGR? I have an 08 Tiguan. Cheers

After cleaning it with a blow torch, I disabled EGR in the computer. I didn't delete it. I just disabled it. Same intake, same PCV system, just no EGR. After another 160k miles on it, the intake is still crystal clean from the first cleaning.

It's the EGR that clogs it, not the crankcase vapors.

 

[ATL Cruiser]

@MUDZLLA you would need either Volkswagen OTIS (big $$) or Ross-Tech VCDS (like $150). I'm not sure it's possible on that vehicle, but if it is, you would look here using the Ross-Tech on your laptop:

Exhaust Gas Recirculation (EGR) Valve Adaptation - Ross-Tech Wiki

wiki.ross-tech.com