Crud Under Oil Cap

[abscate]

5 quarts synthetic $25 on sale. Oil filter $5. 30 minutes in driveway.
Upside..correct torque on fasteners unlike what the tailless monkeys will do at JiffyPop

[zanzabar]

Well, yeah the PCV is bad...but the crud under the cap and the PCV getting clogged up are both caused by the same thing. Not good enough quality oil and/or too long oil change intervals by previous owners. You will have to do a complete PCV system replacement I'm afraid. It can be fairly expensive. 150k and 10 years is about all you can reasonably expect from those PCV parts though so don't be too disappointed.

[bugeye]

Do not delay servicing, replacing the PVC components. The crankcase pressure will cause the seals to leak or blow out. Certainly sludge throughout the engine.

At purchase, the grate under the oil cap on our 2004 XC70 looked similar, but not quite as coated. Our crankcase pressure was negative, After 7 oil changes and 30,000 miles using Mobil1 and Pennzoil Platinum, the grate is clean. Also replaced all the PVC components, verified block drain was open and clean.

[cn90]

This is a repeat of another post, sorry if I repeat things but...

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- The car is 2004 V70 2.5T with 104K miles. All maintenance up-to-date (Timing Belt at 95K, PCV etc.). Car was serviced exclusively at Volvo dealer. I am the 3rd owner.

- Car has slight lifter noise (more than my 2005 XC90 2.5T with 115K, which has exactly the same engine), but overall runs fine, good acceleration on highway, good gas mileage. Car drives great.

- Opened the Oil Filler Cap and saw some sludge. I am from BMW and Volvo forums and am familiar with this issue of engine sludge, but need some updated responses from the "sludge gurus".....

1. Some people say this black stuff seen on the grates inside the oil filler cap is "normal", is this true?

2. I have used Liqui Moly 2037 Pro-Line Engine Flush in my 2006 BMW X5 on a preventive basis (no issue but I did it for the heck of it).
This is the product I am talking about:


https://www.amazon.com/Liqui-Moly-2037- ... B00CR3RXTO

- Anyone with sludge and has any success with this?

3. Some people say forget about Liqui Moly flush and simply use synthetic oil and change frequently, such as every 1K-2K, as the detergent inside the synthetic oil will clean the sludge. Is this true?

4. Any other advices from the "sludge gurus"?

Thanks in advance!

[abscate]

That’s moderate sludge. Not heavy but not light, either.

Increase oil change Frequency

Try some Bell Engineering desludger...idle for 15 minutes with it in, no revving, then change oil

Real solution, drop pan, desludge, evaluate replace oil pump and orings, check crankcase ports , PCV job.

Are you using full synthetic oil in this turbo? That’s important.

I kept my 99 on Dino oil for most of its life with 5000 mile oil change intervals

[93SCMax]

1. Some people say this black stuff seen on the grates inside the oil filler cap is "normal", is this true?
-- I would say this is not normal.
2. I have used Liqui Moly 2037 Pro-Line Engine Flush in my 2006 BMW X5 on a preventive basis (no issue but I did it for the heck of it).
This is the product I am talking about:
https://www.amazon.com/Liqui-Moly-2037- ... B00CR3RXTO
- Anyone with sludge and has any success with this?
-- I don't have sludge, have never used the product, so I won't comment on it.
3. Some people say forget about Liqui Moly flush and simply use synthetic oil and change frequently, such as every 1K-2K, as the detergent inside the synthetic oil will clean the sludge. Is this true?
-- This has been the key to my success. Mobil 1 5w30 and a new Volvo or Mann filter every 7,500 miles. In 150k, I've never had sludge or had to clean the PCV system.
4. Any other advices from the "sludge gurus"?
-- As mentioned, switch to synthetic oil and increase oil changes, but I would try the flush 1st in your case, and even clean the PCV system...your oil fill grate doesn't instill confidence in the cleanliness of the inside of your engine. Shame on the Volvo dealer who did the maintenance.

Good luck with the clean up.

[Georgeandkira]

NOTE ON OILS: For turbocharged engines (read that as HOT) the synthetic oils you want are ACEA rated A3,B3.
Mobil1 0W-40 European Formula is one. Castrol's is a 0W-30 European Formula is another. There are others.
There are also newer formulae which are A5,B5. The A and B refers to gasoline and diesel engines respectively.
Look at the labels of synthetic oils. If there's an ACEA rating at all it'll likely be A1,B1.

And yes, "it can be done" with dino oils but then all the other parameters like trip length, time spent idling and oil change interval redouble in importance.

My oil filler neck grate had less crud than the one pictured. During my car search all the grates I saw were worse.
My vehicle's service history included lotsa brake jobs so I concluded my car must've been a single family school bus.

[Rattnalle]

A2 and A3 are related. Both are high protection oils but A3 is newer and better. These are the required oils up to and including MY04 in Europe.

A1 and A5 are related. Both are low friction oils. A5 is newer and better. These are usually thin oils like 0w30 or even lately 0w20. From MY05 A5 is the required oil. A5 is also usually a long life oil so from 05 the OCI was increased from 20' to 30' km.

These two groups should not be substituted for one another, especially putting a thin A5 oil in an engine designed for a thicker more protecting oil. That said it seems quite common to run a cheaper A3 in the newer cars together with shorter (more reasonable) oil changes of 10'-15' km.

[cn90]

...After 7 oil changes and 30,000 miles using Mobil1 and Pennzoil Platinum, the grate is clean...

Can some gurus explain this?

- I intend to leave the grate crud alone so I can monitor the progress of frequent synthetic oil change (such as every 3K-4K).

- Let's say you change synthetic oil every 3K-4K.

- My question is: does the engine oil gets "sprayed" and lands on top of the grates and with the detergents in the good synthetic oil slowly washes away the black crud? In other words, how does good engine oil clean the black crud?

[Rattnalle]

There will be some small splashes from underneath. You can be sure any little improvement there will be smaller than somewhere the oil actually flows.