Engine Deposits & Varnish

[BrianWC]

Originally Posted By: zulu
Everybody agrees sludge/deposits are not a good thing. I do think there is a bit of excess worry on this board however. I helped my neighbor change the oil in his 02 Avalon. The inside of his oil cap/crankcase should be a poster child for what sludge looks like. It's black and THICK. It's got a mere 159,000 miles on the ticker, but still going strong. 28+ mpg and purrs like a kitten. I think minor deposits/sludge are a normal part of engines and have little effect on engine longevity overall. But I'm just a newbie, so take that for what it's worth.


Yeah, uh, I can show you many pics of sludged saabs where the end result was bye bye engine. The thing you have to remember is a lot of the people who come on here and make a big deal out of deposits/sludge/crud/gunk/whatever have HAD personal experience with them and are looking to avoid past mistakes.

I'm certainly not worried about the sludge in my enine that's purely cosmetic. I've left it there just to watch over time how auto-rx and the other treatments I've used have or haven't dissolved it.

 

[ZZman]

Sludge is not normal. Some varnish is.

If there is sludge in the motor the maintenance/repair schedules needs to be corrected. Earlier oil changes, change to Syn oil, PCV system issues, coolant leak issues, etc....

While sludge will not always kill a motor it does affect its performance. It will cause it to not be lubed properly or dissipate heat properly. It can cause the PCV system to not work properly so the engine does not breath as it should and work properly.

Out of the motors that last 200,000-300,000 miles how many were well maintained and how? Did they change oil every 3,000 miles?
Use Syn oil? Do other maintenance regularly also like coolant, trans, plugs, air filters etc....Was the mileage on most of these motors Hwy miles? Are these long life engines just built better or have better engine designs? There are many variables that can be involved.

 

[TOMBUCK]

WHEN YOU DO AN OIL CHANGE, PULL THE PVC AND SOAK IT IN SOME SOLVENT OR CLEANER TO CLEAN IT, TILL YOU HEAR IT RATINGLY AROUND IN THE PVC AGIN, THEN SPRAY IT OUT WITH SOME CLEANER, LET IT DRY , SHAKE IT AGIN TO HEAR IT RATTLE THEN REINSTALL IT. AND YOU'LL BE FINE....

 

[artificialist]

Originally Posted By: TOMBUCK
WHEN YOU DO AN OIL CHANGE, PULL THE PVC AND SOAK IT IN SOME SOLVENT OR CLEANER TO CLEAN IT, TILL YOU HEAR IT RATINGLY AROUND IN THE PVC AGIN, THEN SPRAY IT OUT WITH SOME CLEANER, LET IT DRY , SHAKE IT AGIN TO HEAR IT RATTLE THEN REINSTALL IT. AND YOU'LL BE FINE....
Sometimes an old PCV will develop metal fatigue of the spring, causing it to hang open and then send excessive oil into the air intake. That is why replacing the PCV can be a must.

And please shut off caps lock.

 

[Ken2]

Originally Posted By: John K
From the paper -

Valvoline pulled a number of turbo-charged Volvo engines out of the field, disassembled them and evaluated the type and level of deposits in them.

Recommendations
Based on detailed analysis of the data Valvoline is recommending that conventional oils not be used in these and other similar high performance engines and that drain intervals not exceed 5,000 miles.
My 1996 Volvo 850 turbo has 166,000 miles, and looks very clean in the oil filler cap...the camshafts are visible with no varnish. I run Schaeffer #9000 and a Mann filter for 10,000 miles. The last analysis report at 9k showed low wear particles, low oxidation (sludge is from oxidized oil), 40 wt viscosity, and said to test again at 11k.

 

[Steve S]

Schaeffers oils are top quality to the point of one of the best oils.