Question on late model VW Gas model. Oil Stick O Ring

[Driz]

I was looking at a girls Oil level a couple days ago . When I pulled it up this little O ring, tattered looking just went sliding down the stick and I grabbed it before it managed to go down the tube. I told he whatever it was she didn’t want that thing sitting there waiting to stuf up the engine . Ok so why in heck did the Krauts have one on there and does she need i???

 

[bdcardinal]

I have seen some dipsticks have o-rings on the bottom of the handle.

 

[Chris142]

It may cause a vacuum leak with out it.

 

[RooflessVW]

Dipsticks need to seal or it's a vacuum leak. Would you rather replace an o-ring or the whole dipstick?

 

[CT8]

Originally Posted By: Chris142
It may cause a vacuum leak with out it.
It will cause a vacuum leak wit out it .

 

[billt460]

Both my 2018 Toyota 4-cylinder, and 2015 Jeep V-8 have a O-Ring at the lower end of the dipstick handle. I keep them clean, with a little light grease on it to keep them soft and sealing good.

 

[tomcat27]

All my dipsticks have the o ring. Even my 1970 Cougar.

 

[Trav]

The O ring missing as others have said will cause a vacuum leak in the PCV system, its critical on VW to have seals inc O rings in place for proper PCV operation. It is also a place that dirt can enter the crankcase and cause excessive wear.

 

[weasley]

I'm a bit confused about this talk of vacuum leaks. The crankcase is pressurised by blow-by; the PCV vents this, usually to the air intake system or to a catch-can. The dipstick is usually a push-fit with an O-ring so that it doesn't blow out of the tube and thus vent the crankcase gases to atmosphere; it helps maintain a positive pressure in the crankcase.

 

[BMWTurboDzl]

Originally Posted By: weasley
I'm a bit confused about this talk of vacuum leaks. The crankcase is pressurised by blow-by; the PCV vents this, usually to the air intake system or to a catch-can. The dipstick is usually a push-fit with an O-ring so that it doesn't blow out of the tube and thus vent the crankcase gases to atmosphere; it helps maintain a positive pressure in the crankcase.


Some PVC systems do operate on a vacuum because some valves activate on/off throttle.

I know the system used for my BMW (N55) operates like that.

See pgs 24-27

https://www.bimmerpost.com/goodiesforyou/N55-guide-BIMMERPOST.pdf

 

[weasley]

Originally Posted By: BMWTurboDzl
Some PVC systems do operate on a vacuum because some valves activate on/off throttle.


Yes - vacuum-operated PCV valves are common. I'm just not sure how a missing dipstick O-ring will introduce a vacuum leak?

 

[Shannow]

Back in the day, PCV had a filter either on the rocker cover or on the air intake...they were essentially open on the suction side, bar a piece of steel wool providing something akin to filtration...crankcase "vacuum" was almost impossible...pressurisation flows made either the rocker cover or the air filter oily...even with PCV valves.

More modern engines don't have the "positive" crankcase ventilation...no mini air filter it's sealed at one end.

So the crankcase can be positively pressured, requiring an O ring to stop leakage at the dipstick (or the dipstick popping out).

Or it can be negatively "pressurised" depending on the amount of blowby versus intake suction. A missing O ring brings air and dirt in through that path

 

[JAG]

On VW 1.8T turbo engines from the late 1990s to the 2000s, people who increased boost would often cause the dipstick to blow out of its tube.

 

[Driz]

Originally Posted By: rooflessVW
Dipsticks need to seal or it's a vacuum leak. Would you rather replace an o-ring or the whole dipstick?



Uhhh I dunno. I’ve been drivin old cars , trucks, boats and airplanes and fixing my own back to 1972 and guess how man
I’ve changed oil sticks on ? ZERO And I drive most of them till the rust monster takes them .
I can see having something on there to help seal it but brother, what I pulled off of there was just an invitation to disaster. I continue to be unimpressed with VW and this is yet another good reason. My last one was a 67 Bug that I got when my 68 Van died in Germany. When I came back to The World I never looked back.

 

[MCompact]

Originally Posted By: Driz

Uhhh I dunno. I’ve been drivin old cars , trucks, boats and airplanes and fixing my own back to 1972 and guess how man
I’ve changed oil sticks on ? ZERO And I drive most of them till the rust monster takes them .
I can see having something on there to help seal it but brother, what I pulled off of there was just an invitation to disaster. I continue to be unimpressed with VW and this is yet another good reason. My last one was a 67 Bug that I got when my 68 Van died in Germany. When I came back to The World I never looked back.


I could not agree more; once a manufacture adds an o-ring to the dipstick I cross that brand off my list!

 

[BMWTurboDzl]

Originally Posted By: MCompact
Originally Posted By: Driz

Uhhh I dunno. I’ve been drivin old cars , trucks, boats and airplanes and fixing my own back to 1972 and guess how man
I’ve changed oil sticks on ? ZERO And I drive most of them till the rust monster takes them .
I can see having something on there to help seal it but brother, what I pulled off of there was just an invitation to disaster. I continue to be unimpressed with VW and this is yet another good reason. My last one was a 67 Bug that I got when my 68 Van died in Germany. When I came back to The World I never looked back.


I could not agree more; once a manufacture adds an o-ring to the dipstick I cross that brand off my list!


And yet you don't mind it when a manufacture omits the dipstick entirely ?!?


Just a FYI..My 335d had a dipstick w/ o-rings.