russellmc301 600 #1 Posted September 3, 2016 (edited) what weight of oil do you guys use for your k-91's? it sayes 30 w so i thinks thats the best Edited September 3, 2016 by russellmc301 Share this post Link to post Share on other sites
953 nut 60,224 #2 Posted September 3, 2016 Any motor oil you purchase today will be superior to oils on the market when your K-91 was built. I use 10-W-30 synthetic blend in everything, others may disagree. 2 Share this post Link to post Share on other sites
SPINJIM 1,986 #3 Posted September 3, 2016 10w30 Castrol Blended Share this post Link to post Share on other sites
russellmc301 600 #4 Posted September 3, 2016 ok thanks Share this post Link to post Share on other sites
wedge 80 #5 Posted September 3, 2016 I have always use Straight weight oil in my air cooled engine other than my Harley. Older engine I would run 40 weight just to help with the extra clearance it gained over the years. 10w30 is for cold starting like in the winter and so on. But oil is always an argument issue ?!?!? Share this post Link to post Share on other sites
russellmc301 600 #6 Posted September 3, 2016 does it really make that huge of diffence if i use 30w or 10w 30? Share this post Link to post Share on other sites
953 nut 60,224 #7 Posted September 3, 2016 No, like I said; any oil you buy today will be better than what was used 50+ years ago. Share this post Link to post Share on other sites
russellmc301 600 #8 Posted September 3, 2016 o sorry i thought you mean't the oil wasn't as good as back then. Share this post Link to post Share on other sites
wallfish 18,188 #9 Posted September 3, 2016 2 hours ago, russellmc301 said: does it really make that huge of diffence if i use 30w or 10w 30? Unlike 99.9% of Dick's posts, just can't agree with this one that it doesn't make a huge difference. Probably doesn't matter as much in N.C. but it gets COLD up here. Try a simple little test and freeze a quart of both types overnight. The SAE 30 will pour more like molasses when frozen. Now imagine splashing it with a small metal stick (which is exactly what's happening inside the oil pan of your K91 engine) or even try to splash it yourself. Now you can make up your own mind from your own conclusions which type is better for use in freezing cold temperatures. IMO using straight 30 in freezing temps is like running your engine with no oil or very low oil until it starts to warm up, each time you start it . (Besides the "W" stands for Winter) Share this post Link to post Share on other sites
russellmc301 600 #10 Posted September 3, 2016 well i really don't plan on driving it during the winter and if i do i know where 2 gallons of 10w-30 . also i will more then likley have it in the headed shop if i plan on driving it. so for now i plan on useing 30w since i made a trip to get some earlier. but i will switch over to 10-30 next time i change the oil, that is if i can get the engine to run. as if now its not starting Share this post Link to post Share on other sites