plasticmaster, I agree, it is important to consider the cost to repair older lawn equipment, even newer lawn equipment! I bought a new Sears lawn tractor that leaked oil at a rate of about one cup a day, starting the moment I first filled the crankcase with oil. Sears came to my home four times to attempt to stop the leak, but ended up replacing the entire engine under warranty. Out of curiosity, I looked up the price of the replacement engine on the Sears web site. It was listed at $1,079.00, only $20 short of the price I paid for the entire tractor.
Coincidentally, the tractor I owned previously suffered a blown engine (connecting rod penetrated the crankcase) after 20 years of weekly use.
While this situation goes back many decades, it proves one thing....... "On the cheap" engineering is NOT a new phenomenon! After literally destrying my 1976 RUPP 340 NITRO (liquid-cooled) snowmobile, I bought a brand-spanking new 1980 KAWASAKI 340 (liquid-cooled) snowmobile. It was a racy looking sled, w/ a bold design and plenty of OOOOOOMPH w/ the gas pedal floored. I could easilt outrun just about any fan-cooled or natural-cooled machine available at the time. The ONLY problem w/ the sled was that that's ALL it wanted to do! Just run wide open throttle all the time. So, IF you wanted to race across a frozen lake or field at top speed or close to the limit, that was fine, BUT if you wanted to do some trail-riding w/ friends (& a passenger on board), FORGET ABOUT IT! After about 1000 ft of trail riding at slow speed, the coolant temperature gauge would peg in the red zone! Petitions to the KAWASAKI dealership went unanswered! Even calls to the KAWASAKI headquarters went unanswered! Even threats for legal action were not heeded! So, with declining snowfall over the succeeding winter seasons, the easiest thing to do was to sell it, and put the loss behind me!
The interlock is an interesting issue. I would have bypassed it completely, rather than open the transmission, since some of those are never intended to be repaired, only replaced. The problem is always that the "safety" interlock is only designed to fail in a machine inoperative mode. Usually there is not really any need for the interlock unless the operator is stupid.
I had a lawn tractor of another make that had issues with the transmission case. Where the axles came out of the housing, there was no bushing, so over time, the hard axle rod wallowed out the cast hole it rode in. After looking around, I found replacing the entire tractor would be cheaper than purchasing major components for these machines.
It seems, mass producing them makes the entire unit cheaper as a whole than any of the individual parts alone.
After considering all of the time it takes to change a cracked switch, I'd have to also weigh that with how long will it take for me to fix it and how long will it take up highly prized floor space in my garage? (more specifically, my work space is where my wife parks her car)
We have a 2000 Cub Cadet that has served wonderfully for the last 11 years until it would not start this year. Finding some electrical schematics on-line, I started tracking down the disconnect whiich I found to be the safety that does not allow the motor to start when the PTO is engaged. Getting to the switch required draining and pulling the gas tank which I did and discovered that the PTO engagement lever rides in a plastic bushing on the frame of the mower. The plastic had cracked which allowed the lever to drift away from the switch. To get things running, I re-inforced the swithc to add some additional stroke, but am in process of a new bushing design to allow for many additional years of great service.
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