Last weekend I successfully completed the eighth oil change on our trusty 1.6 DV6 but there was evidence again of oil leakage....seemingly from the sump gasket but not confirmed.
Got me thinking about my old 2.0 HDi which always looked 'wet' with oil from underneath. Neither of these cars disgraced themselves by actually dripping oil out (think the undertray catches it) but is there anywhere obvious or faulty with HDi's that cause them to leak?
I thought most modern-ish engines are pretty well sealed these days, certainly the Volvo is and the Renner is pretty 'dry' in this respect.
Cars in my care:
2021 Kia Spottage 1.6 Pez Turbo Dual Clutch Gearbox Trickery
2013 Renner Twingo - donkey work
2.0 & 2.2 HDi's don't leak much in my experience, mostly it's crank & cam breathers carrying a little oil back into the induction system then seeping a bit from the subsequent turbo/intercooler pipework. Unsightly but rarely if ever needing a top up between oil changes even if you stick to 12k intervals.
A few people have had crankshaft oil seals weeping a bit, (which might well look like a sump gasket issue).
Seem to recall hearing that there Devil's Vengeance 6(66) has some bonus features in the valve stem sealage area plus the (in)famous gauze that never gets cleaned in the turbo oil line
2002 HDi 2.2 Exec Estate, (2008-12) (wonderful)
2003 HDi 2.2 6-speed Exec Estate (2012-19) (also a gem)
2009 Citroen C5 2.0 HDi VTR+ Estate (godawful heap)
2008 BMW E91 330i touring (great fun - murdered by a reversing SUV)
2007 BMW E91 325i touring (slower smoother quieter)
Mmm, I did wonder about the main crank seal and the oil finding its way down to the sump. To be fair the sump gasket shouldn't leak at all with all that gobbo they use at the factory.
The Turbo housing on my 110 used to be covered in oil....enough to make me avert my eyes just long enough to forget about it
Cars in my care:
2021 Kia Spottage 1.6 Pez Turbo Dual Clutch Gearbox Trickery
2013 Renner Twingo - donkey work
Helps to stop rust. I cant say I have had a problem with oil leaks and I have been running them for 10 years or more. The valve cover gasket is a good place to start as it will run all over the engine.
My 2.0 HDI was always a bit greasy... until it started dripping real bad. Having a good look revealed the crankshaft oil seal was leaking. Replaced it and cleaned things up, still the sump would not stay completely dry. After futher careful inspection I decided to replace the valve cover gasket. I also discovered my self-fitted blanking plate to the EGR pipe at the clean-air inlet side was weeping, so i treated that with an oil resistant liquid gasket. And as Doggy says, had a good look at all the breather pipes, undoing them one by one and making sure they are clean before fastening them with a new, suitable set of hose clamps (the ones from factory are crap). Same for the turbo pipes feeding the pressurised air, they can leak some oil. I also used the liquid gasket to seal the "air doser" thing; its vacuum control pipe has already been disconnected so it is always open, without any function but to leak oil...
Result is that after 5 years of greasiness, the sump is now bone dry
Current "fleet": 2003 406 Estate 2.0HDi 110 - 7 seater - just hit 710.000 kms 2001 Citroen Saxo 1.6i 8v 100
Previously owned: 2000 406 Sedan 2.0 HDi 90 2000 406 Coupé 2.0i 16v 138 - Riviera Blue
PP2000 user, can help with faults / diagnostics in the Netherlands.