Hydrocruiser

Mobil-1 15W-50 EP

Amsoil Severe Service Racing 20W-50

Mobil-1 V-Twin 20W-50

RP 20W-50

Redline 20W-50

Take your pick.

My personal favorite is M-1 V-Twin.

minxguy

Rage, if the fuel is high, this could be diluting the oil reducing its viscosity..........less film strength=more wear. Machine work on the pistons in the block could = more metals in the oil sample, and finally a higher dertergent product could clean better, however you did change your heads which can "hold" a lot of crap. How did the top of the heads look when you changed them? Any sludge at all?
Ken

minxguy

Berns, when you change your oil for seasonal storage, change with the product you want to use in the spring. There is no need to change now and then change again in the spring with no hours on the oil. You will be wasting your money. Ken

Rage

OK, then I should expect to see a significant reduction in wear debris levels when I change the Mobil 1 20W50 that is in the engine now after an additional season of another 80 - 90 hours?

Rage

I was fanatical about keeping contamination out of the engine during the conversion. The lifter/cam area and piston bores were continuously sealed with duck tape to include each piston as I cut (Isky tool) the additional valve relief depth. After polishing the heads and intake manifold all were degreased, power washed and high pressure air blown dry. The OE stamped rocker arms were also replaced with Crane roller rockers which should have helped reduce wear debris. Roller lifters were the originals. The engine ran all season fat at idle and lower rpm's but above that the A/R was dead on. Final ECU reprogramming is in process now.

Rage

Like I mentioned to Sleeper Dave I was fanatical about keeping contamination out of the engine during the conversion. The lifter/cam area and piston bores were continuously sealed with duck tape to include each piston as I cut (Isky tool) the additional valve relief depth. After polishing the heads and intake manifold all were degreased, power washed and high pressure air blown dry. The OE stamped rocker arms were also replaced with Crane roller rockers which should have helped reduce wear debris. Roller lifters were the originals. The engine ran all season fat at idle (~11.5 A/F) and lower rpm's but above that the A/R was dead on.

To answer your question the OEM heads after only 90 total hours on the engine (with the Merc 25W40) were very clean and zero sludge.

Rage

I am still not getting it. How can "some synthetics are 100% GRP III"? Where/what is the performance standard/definition for the term "synthetic" that allows this? As a layman, I am hearing that the primary claim to fame for the "synthetic oil" is that it retains its viscosity much better that non synthetic oil. If that is true how is it again that "some synthetics are 100% GRP III"?

minxguy

Rage, its a definition. Group III basestocks are petroleum basestocks that have been more refined, bringing them "closer" to a synthetic basestock performance. No way are Group III and PAO's equal. When Mobil sued Castrol over the term synthetic, a court of law did not decide the outcome. This out come opened the door for blendeders to call an oil made with this highly refined petroleum oil a synthetic. There is no Group III PAO. PAO's are Group IV and only Group IV. You will be hard pressed to find a quality PAO synthetic for $5.00/qt.ken

Rage

I would rather keep the cost out of this discussion until after I understand what is and is not defined as a synthetic oil based on performance and/or constituent make up of an oil.

I need a little more oil 101 instruction. "PAO" I take it defines only a 100% true synthetic engine oil. It also reads like "Group IV" also defines only a 100% true synthetic oil. It also reads like "Group III" defines only a true 100% petrolium based engine oil. Please correct me where I have it wrong.

minxguy

API base stock categories
Group I base stocks contain less than 90% saturates and/or greater than 0.03% sulfur, and have a viscosity index greater than or equal to 80 and less than 120 using spefic test methods.

Group II base stocks contain greater than or equal to 90
% saturates, and less than or equal to 0.03% sulfer. They have a viscosity index greater than or equal to 80 and less than 120 using the same test methods for each catagory.

Group III base stocks contain greater than or equal to 90% saturates, and less than or equal to 0.03% sulfer, and have a viscosity index greater than or equal to 120...

Group IV base stockes are PAO's


Group V base stocks include all others base stocks not included in Group I,II,III,IV


I am sure this does not help, but these are the classifications.

Ken