engine oil - modern equivalent of CD standard

[John100156]

This seems to be the 'perfect seal' discussion again. I think you are correct that most of the combustion product goes down the exhaust pipe but some of it certainly does not. It may be that some of the acids condense on the bores but what is certain is that the lubricant will steadily become more acidic. The bores are coated with a film of oil that does not burn but is transferred into the sump by the pumping action of the rings moving in their grooves.

My ex-boss was one of a team from Shell Research who sampled lubricant below the top piston ring in a running engine and demonstrated increase in acidity. Link to a one-page summary here https://www.york.ac.uk/res/gkg/posters/add03.ppt

Vyv, Many thanks that's most interesting....

 

[lw395]

Indeed. We collected my Son's new Honda motorbike at the weekend and the Manager explained that we should use mineral oil in the sump for the first 600 miles and then drain and replace it with fully synthetic. I observed that we were doing exactly the same 40 years ago so little appears to have changed.

Richard

What Honda is that?

I'm surprised they let the customer get near the sump oil!

 

[RichardS]

What Honda is that?

I'm surprised they let the customer get near the sump oil!

I meant "we" in the sense that the dealer has filled the sump with mineral oil and, if we need to top it up in the first 600 miles, then we should use mineral oil.

The bike will go in for its first warranty service at 600 miles and the mineral will be replaced with synthetic oil, so from then on, we must use synthetic oil.

I assume that all Hondas receive the same treatment for the same reasons that applied 40 years ago.

Richard

 

[lw395]

I meant "we" in the sense that the dealer has filled the sump with mineral oil and, if we need to top it up in the first 600 miles, then we should use mineral oil.

The bike will go in for its first warranty service at 600 miles and the mineral will be replaced with synthetic oil, so from then on, we must use synthetic oil.

I assume that all Hondas receive the same treatment for the same reasons that applied 40 years ago.

Richard

Sounds like the dealer hasn't read the manual in 40 years.

 

[RichardS]

Sounds like the dealer hasn't read the manual in 40 years.

It's only the Honda main dealer so I guess so.

Richard