Rigorous Field Testing

[rraiderr]

I have a hard time with all the advertising and testing fresh oil leaves a lot to be desired.

This is one of the reason I like Sunrah's posts as he does real world testing and could give a [censored] about what the vendors claim or advertise. I also like the people that post their oil analysis as this data seems more valuable then the vendors advertising and published tests

I wish we had more Sunrah's out there so we could see how all the oils do in the real world.

 

[saaber1]

Re: the earlier discussion of how marketing affects manufacturer's oil recommendations, here is another example of a manufacturer making recomendations based on either EPA or marketing and then later going back to what is right for the engine. taken from the boat subforum:

Originally Posted By: saaber1
My 87ish 15hp Johnson says 100:1 next to where the fuel line connects. I thought these were all 50:1? I think 50:1 is safer.

Was the 100:1 mainly for marketing purposes to show they are more EPA friendly or maybe to reduce smoke. Isn't it better to run 50:1 on an old johnson/evinrude? I know some of the 2 stroke Yamaha's are 100:1.

Found the answer on iboats forum FAQ:

"POST-1964 JOHNSON/EVINRUDE/GALE - The official stance on 1964 and newer OMC engines is to run them 50:1 and it's a good rule of thumb to follow on the bigger motors. OMC also renegged on the late 1980s 100:1 recommendation on the smaller (4-35hp) motors, bumping them back to 50:1. I've found that the smaller (3, 4, 5, 6hp) motors from post 1964 up into the mid-1970s may appreciate a bit of extra oil as they still have some bronze sleeve bearings. I run 40:1 in my '72 4hp, as I have a pile of holed blocks, burned cranks and twisted rods that were run at 50:1."

So they may well have recommended 100:1 for EPA or marketing reasons but the safe bet (and to which they later returned) is 50:1.

This is yet another example of why we should not just take the manufacturer recommendation on authority. We should question it and see if they are saying to do what is best for the engine or what is best for marketing! (or emissions)