This might be overkill but for new engines and rebuilds I’ve been doing the following.
Change oil at 10 minutes, 30 minutes and 1 hour.
The reasoning is if there are high spots they will be chipped off quickly and remaining high spots worn quickly. By changing quickly the possible chips or high spots which will wear quicky will be gotten out of the way.
The oil is still good but with possible metal chips or fine particles probably not heavy enough to sink to the bottom of the sump quickly. There is the process of “tanked” or “stand oil” which is to let oil sit in a container for a long time to let particles sink to the bottom to get the oil clear. I let the used oil sit in a tall container for a week or longer and use that on the next rebuild.
On the question of what oil to use it is confusing.
Given:
There are industry ratings and oil manufacturers generally design something to an agency rating. They don’t design in any extras into a product spec as it will add cost to the design and final product. Companies making an SM grade oil will make an oil that meets the SM requirements or a toe over the line which can be touted as “exceeds”. I see “exceeds” on a few makers labels but have never seen a qualification.
Oil on the store shelves have SAE ratings so staying in the range there is pretty easy, 5-30W with W for winter.
For the API part of SL and SM it gets a bit fuzzy as what makes one oil better than another. When I go down a store shelf the oils all have SL/SM or SM ratings. The C ratings don’t apply and the ILSAC GF-# probably will not make a difference in a winter one lung engine. I’ve read where small engines would be fine with SH and that the various additives moving SH to SL and SM are not important. It seems that any off the shelf average quality SM oil would be fine for a snowblower engine. ??
If an average SM oil is good enough for 7000 miles in a car engines it should be ok for 20-30 hour season in a snowblower. ??
