Dipstick slow oil leak?

[SureshR]

Hi, I have a Scorpio with a 2.2 liter mHawk engine (straight 4 / bosch CRDI / vgt). Anyway, just before I bought it two months back, I saw that the service record for this vehicle showed a dipstick change under warranty.

OK fine, cut O ring or similar was what I figured - but the newly changed dipstick also had a slow oil leak, which is weird. A little teflon tape around the dipstick has helped to some extent, but the causes then expand to whatever causes oil pressure to build up in the engine and vent a small amount of excess oil. In a gas engine it'd probably be s faulty PCV valve

What else do I need to look for? Thanks

. And merry christmas / a happy new year from a ~ 1500 mile roadtrip around the greener and hillier parts of South India.

 

[rubberchicken]

Does the dipstick have a tendency to pop out of the tube ? I think that also points to a bad PCV valve. The Mini Cooper has a PCV system built into the valve cover: if it goes bad, the repair is costly.

 

[SureshR]

Not pop out as much as get slightly loosened. I had to top up a bit less than half a quart over some 2500 miles on 15w40 ci4 (shell rimula r4).

I will check the PCV once I can get it to a service center back home. Thanks.

 

[Astro14]

Most diesels don't have a PCV valve, per se, but they still have a crankcase ventilation system in which oily vapor from blowby is ported back into the intake somewhere, or, if no emission controls, just vented to the atmosphere...

Pretty good bet that yours is plugged up. The crankcase pressure is seeking the path of least resistance, in your case, via the dipstick.

Fix that blockage and your dipstick will stop leaking.

 

[SureshR]

Yup I finally got time after a lot of business travel to look at this and sure enough there's considerable blowby. And oil consumption that works out to roughly 1.3-1.4 liters every 10k km (one and a half quarts in ~ 6200 miles, I've done about 5000 miles on an oil fill and then a half quart and then one quart topup).

https://youtu.be/R9xlk2Jaz6A

(no I haven't done a complete drain and weigh yet, this is based on the volume originally filled and then two subsequent topups)

This engine has run like 20k miles is all so the usual suspects such as turbo seals aren't likely to have failed. PCV valve probably - except under the hood and under the car are clean as a whistle, no oil sprays, and the car isn't emitting white or blue- white exhaust from its tailpipe.

Note - this is running a CI4+ Shell HDEO (Rimula) and the OEM recommendation is their own oil - which doesn't publish specs - or CH4 for an old school sort of CRDE originally sourced from AVL in Austria.

 

[SureshR]

So - the oil seperator/ PC's valve and it's hose had some carbon deposits that were cleaned out and the dipstick smoke and oil spray has stopped for now. Why this clogging in a near new car is another question. This is probably a symptom rather than the root cause.