redsquarebob 27 #1 Posted March 20, 2022 can you use rotella straight 30 weight diesel oil in your kohler 12 hp motor 2 2 Share this post Link to post Share on other sites
redsquarebob 27 #3 Posted March 20, 2022 it says not for gasoline engines no more 1 Share this post Link to post Share on other sites
clueless 2,991 #4 Posted March 20, 2022 I've been using Rotella 40 weight in all my old Kohler K's, 4hp to 16hp for the last 20 + years, no oil related problems. I do live in Florida and most of the time when I use them the temp outside is 70 to 100 degrees, you should be fine with 30 weight. 3 Share this post Link to post Share on other sites
clueless 2,991 #5 Posted March 20, 2022 9 minutes ago, redsquarebob said: it says not for gasoline engines no more That's for newer engines with tight tolerances, oil pressure, oil filters. Your 12 hp Kohler ain't one of those, just do it. 4 1 1 Share this post Link to post Share on other sites
redsquarebob 27 #7 Posted March 20, 2022 i was wondering if your 40weight oil rotella is just for diesels like the 30 weight is 1 Share this post Link to post Share on other sites
redsquarebob 27 #8 Posted March 20, 2022 i got a nice running kohler 12 hp i dont wanna ruin it lol 1 Share this post Link to post Share on other sites
SylvanLakeWH 25,557 #9 Posted March 20, 2022 I’ve used it for years… no issues. 3 Share this post Link to post Share on other sites
Lagersolut 661 #10 Posted March 20, 2022 I've been using the Rotella T-1 straight grade 30 weight diesel oil for 15-20 years . 3 Share this post Link to post Share on other sites
pacer 3,169 #11 Posted March 20, 2022 I would hazard a guess that a HUGE majority of members here on this forum are using that very oil (including me!) .... and, if/when you read ratings (like you tube) you'll find the same. 5 Share this post Link to post Share on other sites
clueless 2,991 #12 Posted March 20, 2022 36 minutes ago, redsquarebob said: i was wondering if your 40weight oil rotella is just for diesels like the 30 weight is Both 40 and 30 weight rotella are for diesels but not JUST for diesels. Diesel engine for the most part are dirty running engines, your Kohler K 12hp is a dirty running engine, probably dirter. 3 Share this post Link to post Share on other sites
squonk 41,109 #13 Posted March 20, 2022 (edited) @redsquarebob I got this k341 at around 700 hrs. It was neglected. Oil like tar and it smoked. I put in Rotella 30W and ran it for 10 years. First couple of oil changes the oil came out like crude. 2 years ago at 1000 hrs. I finally had to tear it down as the balance gears were rattling. This is a picture of inside the engine when I pulled the pan. I didn't clean a thing. Edited March 20, 2022 by squonk 11 5 1 Share this post Link to post Share on other sites
kpinnc 12,028 #14 Posted March 21, 2022 3 hours ago, redsquarebob said: says not for gasoline engines no more Because newer engines have emissions systems, and the ZDDP in it buggers them up. But 30w oil with ZDDP is best suited for flathead air cooled engines. 8 2 Share this post Link to post Share on other sites
lynnmor 7,306 #15 Posted March 21, 2022 4 hours ago, redsquarebob said: can you use rotella straight 30 weight diesel oil in your kohler 12 hp motor Just so you know, Kohler sells 30W high zinc oil for gasoline engines. 3 Share this post Link to post Share on other sites
JoeM 7,874 #16 Posted March 21, 2022 Key notes about oil in the old Kohler singles are, never run them low, and change the oil every 25 hours. There is no filtration on the oil circuit and the only way to remove the dirt is to change the oil. I like to run them good and warm then dump her hot while the most dirt is suspended in the oil. 7 1 Share this post Link to post Share on other sites
oldlineman 1,481 #17 Posted March 21, 2022 All of that! I too have used Rotella 30 for many years with no ill effects. Bob Share this post Link to post Share on other sites
Mike'sHorseBarn 2,998 #18 Posted March 21, 2022 I use nothing but Rotella SAE 30 in all my vintage garden tractors, mowers, and engines. Been doing that for as long as I can remember. I have had some issues finding it recently so if I'm out and see a jug I buy it weather I need it or not. 5 Share this post Link to post Share on other sites
peter lena 8,625 #19 Posted March 22, 2022 @JoeM i,m with you on the hot oil changes , always done that , the drainage is also better , rotella # 30 is the stuff , along with lucas xtra heavy duty green grease , keeps the horse smiling . be switching over plows for decks , soon , weather looks good for a warm up . not much of a winter , but ,its all good , pete 2 Share this post Link to post Share on other sites
JoeM 7,874 #20 Posted March 22, 2022 5 hours ago, peter lena said: weather looks good for a warm up . not much of a winter easy now don't jinx us! Share this post Link to post Share on other sites
ET160 29 #21 Posted March 22, 2022 I have heard that the decertification for gasoline engines has to do with additives that are bad for catalytic converters. N/A here. 1 Share this post Link to post Share on other sites
peter lena 8,625 #22 Posted March 22, 2022 @ET160 thats the point, modern engines , are in their final stages of life, kohler engines are like a basic old school build , zero emissions and no converters , staying with a reliable oil that has no problem doing a simple job , regular drainage and service will do that . for me staying regularly in touch with all of the horse functions is the answer to reliable solid service . more than anything , that gives me a heads up on a problem , just how I look at it . remember keep it greasy , recommend rotella #30 oil and lucas lubricants / greases , for smooth easy working anything , pete 2 1 Share this post Link to post Share on other sites
Lagersolut 661 #23 Posted March 22, 2022 On 3/21/2022 at 8:42 AM, Mike'sHorseBarn said: I use nothing but Rotella SAE 30 in all my vintage garden tractors, mowers, and engines. Been doing that for as long as I can remember. I have had some issues finding it recently so if I'm out and see a jug I buy it weather I need it or not. I was getting it at TSC but they were sold out half the time - Auto zone carries it - usually in the separate diesel oil section . 1 Share this post Link to post Share on other sites
peter lena 8,625 #24 Posted March 22, 2022 @Lagersolut Walmart usually has it in stock . regularly add to my lubrication stash , they also stock lucas greases or should I say warehouse ? pete 2 Share this post Link to post Share on other sites
richmondred01 2,237 #25 Posted March 23, 2022 Discussing oil is like discussing politics, religion and sports teams. Personally use rotella 30 in all my k and Magum engines. I also use it in my flathead Ford engine. I change the oil every 20 hours in the old Kohlers and once a year or 3000 mile, in the 40 Ford. (However, I have never put 3000 miles on the 40 in one year it works out to be about 300 miles). 1 Share this post Link to post Share on other sites