I myself would really like to know any and all information from real life use of the Courage single engines that has prolonged their life. I think it would be useful in the future for all who own them that come on here with concerns. Someone who has gotten several hundred hours from one would in my opinion be very useful. My dealer has seen only one Courage twin fail in the last few years. He sold and serviced it himself. The Zturn it failed on was used to mow a cemetary was over two years old and had 757 hours on the clock. He had changed the oil in it just one hour before it failed by slowing down and locking up. Engine was never torn down by the fellow who bought it for scrap. He replaced it with a engine from a wrecked mower. I looked at the engine myself and it indeed was full of new oil and locked up. Oil pump failure was the general thought. That is the only one I have seen from that dealer. He is a small dealer. The most important thing I can think of on these engines is why they fail and how to prevent it.
I'll share my experience with Kohler engines. I have the "dreaded" SV 590 on my Troy-Bilt Super Bronco riding mower. I acquired this mower from a friend when it was two years old. He upgraded to a zero turn Toro and this Toro has the same Kohler single cylinder engine on it. He and I maintain a cemetery and it takes me about two hours to mow my half. I mow the cemetery once a month. I also mow my yard and the yard next door which takes one hour and I do this at least once a week but lately twice a week. I maintain the property at a church which takes me about seven hours to mow (I do not know how many acres) and I cut this every other week and last I cut a few lawns which adds another three hours a month. I do not have an hour meter on this mower, yet, so I cannot tell you how many hours it has on it but I have been using this mower in this capacity for four years and he used it extensively for the two years prior to that. Our mowing season starts in April and ends in October so for seven months out of the year this mower will see a lot of use for a residential unit. I come up with approximately 25 hours per month and I know this is not a lot for a professional but I do not do this for my primary income so I do not consider myself a professional.
Now if you take an average of 25 hours a month and multiply that by the mowing season here which is seven months, you get 175 hours a year. Multiply 175 by 4 (years that I owned the mower) and you get 700 hours on the machine. I do not know how many hours my friend put on the machine but I will guess at least 150 on the conservative side and this puts the total at 850 hours. The 850 hours is an approximation so give or take 15% either way but that still makes the hours on the engine over 700. This is the original engine and it has never been opened up. I have had to replace the valve cover gasket due to leaking but other than that I have not made any repairs to the engine.
Now on to maintenance. I change the engine oil every 50 hours (approximately every other month) and I use the generic blue bottle oil you can buy at Walmart. I also use a product called M.O.A. manufactured by BG Products. I have extensive knowledge and experience (over 27 years) with M.O.A. and I will not run a four stroke engine without using the product. I check the oil before starting the engine, clean or change the air filter as necessary and perform any other needed maintenance as required. I even go the extra mile by lubricating parts that do not have a grease fitting such as the front axle/wheel bushings and I clean the deck after each use by checking the underside and using my leaf blower on the top to remove any moisture-retaining debris. I probably spend more time doing all the little "extras" compared to the average home owner but for some strange reason my mower lasts a lot longer and requires a lot less repair. I can replace the spindle bearings for $1.75 each and it takes about 15 minutes to rebuild a spindle. I usually replace the bearings once a season whether they need it or not as I want to prevent a bearing from going bad when I'm in the middle of a job.
I know I got off on a rabbit trail but I wanted to share my experience with you as requested by possum. Why do some Courage engines last longer than others? I cannot say for sure but I do know that I did not get one of the lemons. I plan to use this mower for another season or two and then purchase a zero turn (maybe my buddy's Toro when he upgrades again). Maintenance plays a large role when it comes to longevity but some of these engines are failing early. General Motors had a bad casting at the foundry and many small block 305 c.i.d. engines would consume coolant but not leak it externally and it was discovered there was a crack in the lifter valley that would allow a small amount of coolant to seep into the engine over a period of months. This small amount of coolant would not cause the familiar "chocolate milkshake" but only drain the overflow bottle over a period of several months. Does Kohler have the same problem such as a bad foundry casting? Maybe, but percentage wise I would like to know just how many Courage engines failed. Keep in mind that there are thousands upon thousands of Courage engines out there so again, percentage wise, how bad is it really?
I hope this adds to the discussion in a positive way and that someone will benefit.