Unit is a Kohler air cooled in a lawn tractor. Mfgr says use 30 in the summer, and a lighter weight in winter. I like simple, not having a collection of bottles all over the GD garage. If I were to use a high quality 10W-30 dinosaur oil like Rotella, instead of straight 30, do I get
Unit is a Kohler air cooled in a lawn tractor. Mfgr says use 30 in the summer, and a lighter weight in winter. I like simple, not having a collection of bottles all over the GD garage. If I were to use a high quality 10W-30 dinosaur oil like Rotella, instead of straight 30, do I get a big carbon buildup?
I have a 17.5hp kohler in my John Deere ride on mower. Short answer is, don’t run multigrade oil in an air cooled four stroke regardless. Multigrade oils have viscosity improvers to widen the temperature gap, these vi’s break down due to hot spots in engines, and or gears, air cooled engines being the worst for temperature variations due to the style of cooling. My John Deere was purchased second hand from my nephew who bought a new one, it had around one fifty hours from memory(I was told this was low for its age) yet it blew blue smoke on start up and the oil was very very dark in colour regardless of service intervals carried out(an indication the oil it is not doing its job sufficiently & viscosity improvers have torn apart). It also required oil between changes(indication it needs changing) the oil previously used was and has always been as per the manufacturers book a 10w30. The only good thing this does do is keep the parts supplier happy and mechanics that understand, frustrated. Straight 30 mono is what it runs now, as it should, has had four changes, uses no oil between changes, the oil is staying clean, blows no smoke, starts better, runs smoother, runs quieter. Sadly his new one, now out of warranty is doing the same thing!!! But he just keeps taking it back for services and they put the multigrade back in
Hello Turtle!
Funny thing is, a John Deere dealers mechanics(different town now) we’re asked what they run? They said 10w30 for those under warranty and a straight 30 when it runs out, or if it’s my own a straight 30!!! I’ve been caught and it ain’t happening again, I’d would much rather have kept the seven grand in my pocket that that stuff up caused to my 42’ jeep engine, due to an oil manufacturer not labelling their so called straight sae40 what it really was … a 25w70
same due cause to hot spots old engines have. No different to our push mower with the Honda four stroke on it, they say 10w30… but from new it ran a straight 30, ran fine until it’s life changed to a 10w30, unknowingly at the time as I purchased it from the now new shop owner, pumped from a 44. harder starting, black oil, burning oil, blowing smoke, yep a 10w30!! Years before I knew any of this my Honda firefighter went from fine to needing a rebuild, yep from a 30sae to a 10w30 & 20w50, killed it. Been running fine on a 30 now since 1998. Look at Briggs & Stratton though, they still recommend a straight 30sae in air cooled engines, for this very reason and anyone I know that buys there 30sae regardless of what brand of mower is having no issues oil wise. I use Lucas, Gulf Western or Atlantic here.
So you may shrug it off and that’s fine, but it’s always good to learn from facts even if we have to find out the hard way. I prefer to just cut the grass or more like slash the paddock and get that job out of the way, I don’t want to be fixing or buying new mowers that being for the wrong choice of oil, oils ain’t oils hence the many posts we see.
