Originally Posted By: BrocLuno
Originally Posted By: ARCOgraphite
Not thick or thin but the right viscosity.
Didn't anyone learn anything from "Goldilocks and the Three Bears"
Engines want what THEY want, not what YOU want them to have
There you go. Oil needs to fit the current bearing clearances, the condition of the timing set and the valve train. Run what works, not some brand loyalty of stuck on some advertised viscosity.
If the coolant leak is truly fixed, I might suggest Delo 400 15W-30 SD (severe duty) and see what results you get. The number will be different. The add pak is different. The reaction with deposits will be different and that will toss off ions that have been trapped behind varnish and stuck in corners.
Most Fe metal comes from cylinder wear, or timing sets coming apart. Can't tell just based on UOA ...
This engine has sliding, not rolling, rocker arms, resulting in more iron wear in the valvetrain than newer engines with rolling rocker arms. I think about half the iron is coming from the camshaft as a result. There is a timing belt, not a timing chain.
As I said, I used HDEO for six years. I am no longer a fan of HDEOs in gasoline engines. First and most, they are too thick for gasoline engines. Second, it's a myth that HDEOs are cleaning oils. Some people believed that because HDEOs contained more dispersants to dissolve soot, it results in more cleaning. However, API SN oils are loaded with dispersants to fight sludge. They are specifically made to clean gasoline engines. Also, I don't think more ZDDP in HDEOs translates to less wear in gasoline engines. Modern PCMOs have excellents AW/EP additives (trinuclear moly etc.) synergistic to ZDDP that greatly enhance the AW/EP performance.
Excerpt from my post that mentions my HDEO use:
Originally Posted By: Gokhan
I will repost the three newest UOAs and post two older UOAs. The 03/24/2013 UOA is TGMO 0W-20 SN and the 6/27/2012 UOA is Pennzoil yellow bottle (PYB) conventional 5W-20 SN. Note that before the Pennzoil 5W-20 SN, I ran 15W-40 HDEO, mostly Mobil Super 1300 15W-40 CJ-4, for about six years. Before that it was 10W-30 conventional, and before that it was 10W-40 conventional.
(See the post in previous page for the UOA images.)
One interesting trend is that the iron decreased after I switched from PYB 5W-20 to TGMO 0W-20 and kept decreasing until it became stable at 12 ppm. However, it jumped again when I switched to M1 0W-40. This doesn't necessarily mean that PYB was a bad oil. As I said, before PYB, I was running 15W-40 HDEO for six years. It could be that HDEO was causing more valvetrain wear because of less oil flow and the effect carried into the OCI with PYB.
Another thing we cannot rule out is that TGMO 0W-20 SN may have the excellent trinuclear moly antiwear/extreme-pressure additive and lots of it (116 ppm), which may be reducing the valvetrain wear, rather than more oil flow reducing the valvetrain wear.
Originally Posted By: ARCOgraphite
Not thick or thin but the right viscosity.
Didn't anyone learn anything from "Goldilocks and the Three Bears"
Engines want what THEY want, not what YOU want them to have
There you go. Oil needs to fit the current bearing clearances, the condition of the timing set and the valve train. Run what works, not some brand loyalty of stuck on some advertised viscosity.
If the coolant leak is truly fixed, I might suggest Delo 400 15W-30 SD (severe duty) and see what results you get. The number will be different. The add pak is different. The reaction with deposits will be different and that will toss off ions that have been trapped behind varnish and stuck in corners.
Most Fe metal comes from cylinder wear, or timing sets coming apart. Can't tell just based on UOA ...
This engine has sliding, not rolling, rocker arms, resulting in more iron wear in the valvetrain than newer engines with rolling rocker arms. I think about half the iron is coming from the camshaft as a result. There is a timing belt, not a timing chain.
As I said, I used HDEO for six years. I am no longer a fan of HDEOs in gasoline engines. First and most, they are too thick for gasoline engines. Second, it's a myth that HDEOs are cleaning oils. Some people believed that because HDEOs contained more dispersants to dissolve soot, it results in more cleaning. However, API SN oils are loaded with dispersants to fight sludge. They are specifically made to clean gasoline engines. Also, I don't think more ZDDP in HDEOs translates to less wear in gasoline engines. Modern PCMOs have excellents AW/EP additives (trinuclear moly etc.) synergistic to ZDDP that greatly enhance the AW/EP performance.
Excerpt from my post that mentions my HDEO use:
Originally Posted By: Gokhan
I will repost the three newest UOAs and post two older UOAs. The 03/24/2013 UOA is TGMO 0W-20 SN and the 6/27/2012 UOA is Pennzoil yellow bottle (PYB) conventional 5W-20 SN. Note that before the Pennzoil 5W-20 SN, I ran 15W-40 HDEO, mostly Mobil Super 1300 15W-40 CJ-4, for about six years. Before that it was 10W-30 conventional, and before that it was 10W-40 conventional.
(See the post in previous page for the UOA images.)
One interesting trend is that the iron decreased after I switched from PYB 5W-20 to TGMO 0W-20 and kept decreasing until it became stable at 12 ppm. However, it jumped again when I switched to M1 0W-40. This doesn't necessarily mean that PYB was a bad oil. As I said, before PYB, I was running 15W-40 HDEO for six years. It could be that HDEO was causing more valvetrain wear because of less oil flow and the effect carried into the OCI with PYB.
Another thing we cannot rule out is that TGMO 0W-20 SN may have the excellent trinuclear moly antiwear/extreme-pressure additive and lots of it (116 ppm), which may be reducing the valvetrain wear, rather than more oil flow reducing the valvetrain wear.
