Why is NOACK/volatility loss a big secret?

[Nyogtha]

Yes but those vapors wouldn't carry additives, no?

The first real process step in Safety Kleen's used motor recycling is very gentle thin film evaporation, followed by distillation, undoubtably to minimize the quantity of non-base oil additives carried to the downstream processing steps. Most such additives are irreversible poisons (deactivators) for the hydrotreating catalyst, just like the organometallic components of crude oil, along with VII to be rejected to recover base oil.

 

[FlyPenFly]

With how crazy everyone is in the BMW and Audi forums about intake valve buildup, it's widely accepted there at least that catch cans make no discernible differences in buildup across several members.

I for one, wish it were that easy. Just add a $300 catch can and don't worry about valve build up. If it was even half effective, it would be a huge win. Unfortunately, it's widely seen that Seafoam through intake and catch cans are all ineffective. Periodic manual cleanup is the only solution.

 

[Nyogtha]

It would be interesting to see efficiency ratings for catch cans, like oil filters, as physical seperation devices. The first such imptovement ftom a simple demister would be to add cyclonic action, but doubtful there's enough delta -P to work with to get much efficiency imotovement over simple impaction / agglomeration designs.

 

[d00df00d]

Originally Posted By: Nyogtha
The first such imptovement ftom a simple demister would be to add cyclonic action, but doubtful there's enough delta -P to work with to get much efficiency imotovement over simple impaction / agglomeration designs.

Many cars have cyclonic separators that just drop the condensate back into the sump. My old '96 M3 had one. IIRC the B7 RS4, the car that initially popularized the DI intake valve deposit fiasco, has a triple cyclonic separator.

 

[Nyogtha]

Thankfully I've never had a DI engine, IMO. I plan for my current 5.7L Ram to outlast me.

I don't know the details of the NOACK test apparatus & method but if it doesn't include the agitation that an engine sump goes through with sqiurters & sprayers I'd say it only shows a part of the picture. Excess volatile matrial should vaporize & combust to a new equilibrium within a smaller number of cycles through the engine oil system relative to the total number of engine cycles in an OCI.