Viscosity and ring seal

[Nederlander75]

Is there any reason to believe that a 10w would provide better ring seal over a 5w or 0w at start up/warm up in a new low or no mileage application?

 

[Colt45ws]

No. I have actually read the exact opposite, though I do not remember where.

 

[tomcat27]

no, I would not make that assumption. when the oil is cold, the 5W probably seals better because it flows better.

 

[Nayov]

I would say yes, but my experience is with a lawnmower. I bought a new one in May and started using 0-30 (M1). It would puff smoke on start up. I swtiched to 10-30 (SuperTech) and no more smoke.

 

[BuickGN]

I think it can work both ways.

My TL felt faster when I switched to the straight 30wt, especially at WOT and in vtec. The only explanation I can think of would be ring seal. Now of course that's using the butt dyno so I really hate to say that without numbers.

I have to wonder if oils that stop consumption provide a better ring seal or just don't make it to or past the top compression ring.

 

[element_42]

To support BGN's observations, I'd venture to say the least VI modified oil seals the best. Another way to put it might be that the most dense fluid seals a ring the best much in the same way tar can seal a roof, but not shaving cream.

 

[mechtech2]

As I understand it, thin oil gets into and lubes the ring/land area better than thicker oil.
But as for sealing a bad ring/bore area that causes oil use, a thicker oil usually helps.

 

[Nederlander75]

Thanks all for putting some more technical thought to my pondering. Id been told awhile ago when dealing with a fuel diluting EVO to stay with a 10w to help ring seal, which did stop the fuel dilution completely. Never had too much tech put to it though.

Thanks again