Trying Diesel Oil in Kohler

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Mar 20, 2014
So I am dumping the 10w-30 MC syn-blend from my kohler courage 26hp and switching to SAE 15W-40 diesel oil (1 Quart) and a quart of SAE 10W-30 diesel oil. Anyone think this will help clean the engine out before I switch to AMSOIL? And I am assuming this is probably a conventional lube, right? And it says on the bottle "Do not use in gasoline engine equipped with catalysts." Do kohler courage 26hp's have catalysts?
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Alright! Thanks. And will the diesel oil help clean up the engine more than my previous oil?
I was running Rotella 5w40 in my air cooled engines for a couple years. Right now I am running 5w40 Maxlife. In 100+ degree weather I don't trust those tiny cooling fins to do a great job, and I want something synthetic so that it will hold up better. I don't see why your mower shoulden't love 15w40.
I have Rotella T5 10w-30 in the Kohler on my Simplicity lawn tractor. No intention of doing a UOA, but everything seems fine. My engine is "clean" as-is, so I'm not running T5 for cleanup. What are you trying to clean that you think you need a Diesel oil over something else?
Originally Posted By: SuperDave456
I don't see why your mower shoulden't love 15w40.
Do a google search for the model, and look at all of the results that recommend 10w-30 as the heaviest oil that should be used.
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