Ex: I would go with 10W-40 Syn . Why ? Because of it's age and probable compression has dropped down a little . The 40 weight will reduce blowby and consumption in summer and the 10 weight will still allow you easy starting in the colder winter mths. As for the lawn mower straight 30 would be the best possible oil for an older grass mower in my opinion .
Note: Just got off the water and have the Walleye Fillets already in the deep fryer . Have the Generator topped off and ready for the Nascar All-Star Race on my lap top. I guess I had better check out the Beer Cooler lol So much for the rain 75 F will not a cloud in the sky , gotta love them forcasts...Eh ? :)

Hey ewalk, I like the way you rough it up there in the "far north." :-)

yeah, that's about what I'd figured. I'd read posts where the recomendation was to go half dino and half synthetic on the old engines the first time, then go all synthetic. Don't know that makes a lot of sense to me, if it's better, it's better.

If you don't like your forecasts, come down here, they're very consistent, rain, rain, and oh yeah, yet more rain. Yesterday was really weird, there was this round white thing in the sky? After much discussion, fueled by trips to the cooler in the barn we concluded that it must be the sun. We're still not sure as we haven't seen that since feb. or so.....:-)

Ev

Synth is awesome. I use 5W-30 year round in all small engines I have (including some old ones). In the older engines, based on the digital tach, it did smooth out the idle a bit.

There is a website BITOG (bob is the oil guy) that goes into painful detail of all the oils and what they provide, if you are interested.

-gh