I recently purchased a pricy zero-steer riding lawnmower from Troy-Bilt, a Mustang with a 50-inch deck. The design is such that there are two independent hydrostatic drives to each of the rear wheels, enabling the zero-steer capability.
After approximately seven hours of use, I started to lose torque to one of the wheels. Concerned, I jacked up the mower, crawled under it, and found that the drive belt had a twist in it. The drive belts on riding mowers are simply V-belts routed around a series of pulleys. One belt supplies power to the drive wheels and another supplies power to the mower deck. Since the machine was assembled by employees at the store where I bought it, I figured this was just an oversight. I corrected the belt and was back on my way.
It didn't take long for the condition to repeat itself. With the belt corrected, I feared that one of the expensive hydrostatic drives had gone bad. It was severe enough that I would have to have the unit repaired. This did not sit well.
I decided to try fixing it myself before I went through all the time and expense to return the unit for repair. I went online to see if there were any threads referring to hydrostatic drive slippage on riding mowers. There were some that talked about the oil getting low and causing the problem. I then checked my manual to find that my drives were sealed, so there would be no oil leak, and they wouldn’t need to be topped off. I then did some testing of the drive system on a steep hill to ensure that it was only the one drive that was having a problem. I found that the other side was also having a problem, but it was not as bad as the initial side causing the issue. That was actually good news. I couldn't imagine that both independent drives would go bad at the same time and after only seven hours of use.
Since I have a car lift, I lifted the mower up in order to get a better look at the drive belt system. I was getting the feeling that it was the culprit. Since the drive belt is routed from the engine pulley to one side drive and then the other, it is possible that if it were slipping, then the side closest to the engine drive pulley would slip the least and the conditions that I was witnessing could be explained.
When I looked at the drive belt again, it was once again twisted. No blaming it on the store employees this time. I then noticed that the tensioner arm sat very close to a bolt head that was underneath the engine securing the engine to the frame. I manually articulated the tensioner and found that the tensioner arm could hit the bolt head, which would cause a momentary loss of tension on the drive belt, allowing the belt to twist and lose its tractive power! What a huge blunder!
It was a miracle that I found a button head bolt exactly the same size in my shop to replace the standard hex head. This way, there would be nothing for the tensioner arm to hang up on. I also radiused the tensioner arm with a grinder so that there were no sharp edges to catch on anything else. Finally, I got a new belt, one that was a little bit shorter than the original, to help pull the tensioner away from the trouble area and give more tension on the belt.
After spending several hours of my time fixing something that shouldn't need to be fixed, I can say that the mower is now better than new.
This entry was submitted by Chris Clouser and edited by Rob Spiegel.
Tell us your experiences with Monkey-designed products. Send stories to Rob Spiegel for Made by Monkeys.
I bought a cheap elliptical / exercise bicycle. I didn't know if it would get much use. And if it did, then I could justify a more expensive unit. It quickly developed a clunk in the pedals. I disassembled the covers to inspect the drive, expecting to find the bearings were failing. The belt had a fixed tensioner, not spring loaded - the pedaling resistance was adjusted by a drum brake unit. I don't know how they assembled the tensioner - the belt was ridiculously tight. I had to struggle to unbolt and remove the tensioner - it was at the end of the adjustment for 'looseness'. After several minutes of pondering I re-routed the belt and re-installed the tensioner. The belt is now snug vs. piano string tight. And the clunk is gone.
There is some question about the amount of care put into various products and their manuals. In this case the subject is about a Troy mower, and reference was made to their parent company, MTD. If you look up reviews on the internet you will find many complaints about MTD products.
I had an electric lawn mower made by one of their companies. It looked like a simple design that should be fairly trouble free. The manual included standard information about cleaning the cutting deck. When my mower overheated and stopped working I did more exploring. I found that a plastic cover over the motor was used to direct cooling air over the motor. The cover was not designed to be removed for regular servicing. I had to more or less destroy the mower to get it off. Then I discovered that the space between the cover and the mower was packed with grass clippings. Not only did the manual say nothing about cleaning this area, there was no way to do it.
I too have learned (the hard way) about MTD products. I think that my mower was designed to last a year or two, and then be thrown away. I do not want items in my life made that way. I now look at online reviews as much as possible. I also use Consumer Reports, but they usually do not have any useful information about long term use, and servicing problems.
The big problem, as shown in the Made by Monkies series is that no one brand seems to stand out for giving good service. For those of us who value good engineering and good quality it is a real problem. What can you buy that will provide reasonable service?
Chris - I admire your tenacity in troubleshooting the problem. It seems that you should have been the design engineer on this mower. It also makes me wonder how much testing is done during the development stages for these types of products. It seems like this problem should have been recognized during product development.
Good point, Nancy. This blog could just as easily be a Sherlock Ohms entry, since Chris went through the process of identifying the problem and coming up with a long-term fix.
Looks like another "Fixed by Clever Humans" column. I especially like how the author changed various dimensions, like distance from tensioner arm to bolt head and belt length. I agree with Nancy, he should have been the design engineer for this product.
Yes, Ann, another "Fixed by Clever Humans" column. I do wonder, though -- did the manufacturer bother to test this design? From what I'm reading here, the design flaw could have happened on any or all of its mowers. Shouldn't they have picked that up in test?
It seems like all the "Fixed by Clever Humans"--oops, I mean, "Made by Monkeys"--columns are about products that were never tested, or at least, never tested in any way that's relevant to their actual use.
Good point, Ann. I don't know if Chris went online to see what other owners were experiencing with this lawnmower, but I would suspect there is a forum with a thousand complaints. This sounds like a design flaw rather than an individual problem.
I have found numerous opportunities to choose better bolts, knobs, transistors, resistors, capacitors, etc. on various pieces of equipment in my days. And certainly, in many cases, I could have written a better manual after spending only a few hours with a product. I could certainly spell better than they did.
We shouldn't expect perfection with most devices. They only had to meet spec for marketing. He was lucky to have a lift and to see the problem. I wonder how many of these were sold off on Craig's List to some unwary soul who spent a fortune on repairs never to be satisfied?
For an item this expensive with only 7 hours of use, it surely would have been covered under warranty to troubleshoot the bad design. There may have been a technical bulletin explaining the issue that the repair tech could have reviewed.
Problem with a warranty claim, is you will only get the product repaired to the faulty design standard.
There are many times when I regard what I buy as not so much a product, more a set of parts from which to assemble something better.
I have a self-propelled Troy-Bilt walk-behind mower. In 7 years of ownership, I had to replace the rear drive wheels, the front axle, front axle support bushings (three times!), rear drive transmission, and four drive belts. The paint flaked off the inside of the deck years ago. To be fair, when it is working, it works well, but I have invested 50% of the purchase price to keep it running for the last 7 years! More evidence that the monkeys work for Troy-Bilt (and their parent, MTD)! I will NEVER buy a Troy-Bilt product again!
I have a Troy-Built leaf vacuum/chipper which does neither job satisfactorily. Run to repair-time ratio is about 2:1. It is too good to throw away and I don't hate anyone enought to try to sell it to. My impression is Troy-Built made a name for themselves making what is arguably the worlds best Rototiller, then sold the business to MTD who apparently is run by bean counters interested only in short-term profit. Replacement parts are unavailable; assemblies are sold in big-box-stores with no after-sales support, factory service is unavailable and the buying public is largely unaware of other purchasing options. Designed-by-Monkeys indeed! Designed by a committee may be more accurate.
I absolutely agree! Although I do have a 5hp MTD snow thrower which has been 100% reliable for the last 5 years, and does perform well. So maybe the bean counters/committee missed this one!
He did mention the machine was assembled by employees at the retailer. I have this vision of some highschool boys earning minimum wage turning wrenches and finding one hex head bolt that they have no tool for. "Hey Bubba, go to the hardware department and find me a bolt of this size with these threads." The original fastener then went into the trash, the unit worked, the boss was in happy denial, and the customer suffered after seven hours! Did the parts manual show a hex bolt or something special? Home Depot type places do not hire "professional" assemblers and do not have any quality assurance programs. I have seen these methods of misassembly before, even at the professional level.
Island_Al; Pardon me while I RANT: It's always easy when it is someone else's problem. Sort of like the other thread about the missing crank bearing cap - such an easy-to-find problem.. Human Resources and Upper Management seem to have no respect for 'hands-on' and technical workers. It is possible the mower was assembled by student 'less-than-minimum-wage' workers, who had never seen a mower before. I was at one stone shop that had installed a $250k machine, and then hired students to run it. I thought that might be a good idea because students might be more computer-savvy. The real reason was students could be paid less than minimum wage. At Panasonic Factory Automation we had a consultant session to explain to us that machines didn't have to be assembled in a strict order. For example, her husband had to read instructions to assemble their daughter's bicycle, when clearly it wasn't necessary. My response was that the handlebars go through the stem more easily before the basket is attached. And surface mount assembly machines are a little more complicated than a bicycle.
My other rant is 9/16-18 thread. It can be right-hand, left-hand, taper pipe, straight pipe, SAE, JIC, swivel-pipe, gasket seal. O-ring seal. Just because you can make it fit, doesn't mean it is the proper fitting for the application. I have had to just shake my head and walk away from some self-proclaimed 'experts'.
I received an email from the Product Marketing group at MTD Consumer Products. The message came from the manager who handles the Zero Turn Rider Product line, under which this blog falls.
He noted that "When this was brought to my attention, I engaged our Chief Engineer. We have since made a change to the drive belt on this model, shortening it almost an 1". That has rectified the issue Chris Clouser discusses in the blog."
He also noted he could have a new belt sent to Chris' attention.
1) TROY-BILT used to be very respectable garden-maintenance equipment. As another blogger pointed out, when they were gobbled up by MTD, that product quality ethic was the first thing to be thrown into the dumpster!
2) So many of these "horror stories" are about products purchased recently. I wonder IF the engineering depts. at these manufacturers have switched over to "ultra-advanced" 3-D CAD design software, relying solely on its ability to ferret out any incompatibilities and/or impossibilities? Then, totally relying on those drawing sets, go into full-scale manufacturing mode, only to either discover (OR deny!) any problems when the product is in use.
3) In all the years that I've read these MADE by MONKEES, SHERLOCK OHMS, etc., I believe this is the first time I've seen it reported that the manufacturer has directly responded to the complaint. In that regard, one MUST give the people @ MTD a gold star for being forthright. Maybe someone there DOES have a conscience????
Good point on the Gold Star for response, Old Curmudgeon. I can recall a couple other times. One was a writing tablet producer, and I think the other was Harley Davidson. I don't know how they find out about Monkeys. Maybe someone forwarded the link.
My first Troy Bilt riding mower was amazing. I found it dead in a pile of trash. I asked the owner if he was really throwing it out and he said yes. He said it was a goner, but I think that is just what he told his wife so he could buy a shiny new John Deere.
I pulled it from the rubble and replaced the failed mechanical fuel pump with a 12 V generic automotive style. I also installed a new "old-school" starter solenoid and bypassed all the troublesome safety interlocks. Fired right up. A second life.
I used it on my ranch under severe conditions for another 5 years until the engine finally started billowing black smoke. I did have to fix it a couple of dozen times, but it didn't bother me as much as having to fix something that was brand new.
I refused the belt from MTD, because I already bought a new belt. It would be nice to recover several hours of my time troubleshooting this problem and hopefully helping Troy save hundreds if not thousands of customers similar grief. I'm sure the check will be in the mail.
As I wrote recently in another blog, these major suppliers of appliances, consumer equipment, etc. have done a fantastic job of consolidating & shielding. Look at the sheer numbers of companies incorporated as "LLC", or "LP" ,etc., specifically for the purpose of shielding themselves from litigation! In a similar vein, consolidation in the appliance industry has led to the attitude within the corporate heirarchy that 'if they lose a customer here or there, it doesn't matter. There's more customers 'over there''. So, if someone in Ames, Iowa gets P.O.ed at MAYTAG for a lousy product, there will probably be 10 people in Santiago, Chile who will buy that exact same appliance. And, so it is with globalization......
Someone suggested that the fact that MTD reacted to this person's complaint was amazing in itself. HEY! They're human beings AND engineers too. So, I'm SURE that they're all reading these same blogs on a daily basis, just as the rest of us are. But, when the "bomb" dropped in their backyard, someone sought to defuse it promptly. Whoever that person was @ MTD, he (or she!) should have gotten a plaque AND a preferred parking space!!
In this case, Old Curmudgeon, the employee at MTD noted that the problem cited in this Made by Monkeys blog was identified and corrected -- probably due to countless complaints and returns. It seems to me a bit of testing in advance could have saved tons of trouble for everyone.
Like I've harped on so many times in the past ...... Maybe IF more time was spent assembling ACTUAL components of an item, instead of relying on advanced CAD software to identify the trouble spots, we'd have better products.
Many decades ago I was a project engineer for a manufacturer of sophisticated radio communications equipment. While it was a privately-held company, it was a very successful company with peak employment in the days following the first Oil Embargo 0f 1973 of 300 people.
Now, it was that the owner of the company was an avid deep-sea fisherman also. And, in that quest to satify his passion, he had a very comfortable sport fisher style yacht. It also served as a floating laboratory (I'm sure the I.R.S. was amused!). But the point is that we never introduced a new piece of radio equipment WITHOUT it being first installed & extensively tested on the boat. As a result many of these systems were installed on ocean-going freighters, super tankers & advanced drill rigs from the North Sea area to the Mideast Gulf regios.
I'm NOT suggesting that we NEVER sold spare parts, OR that some of the equipment suffered outages, but we DID catch the bulk of the oversights. faulty designs, etc. BEFORE they reached the customers' facilities, all in an effort to preserve the good reputation of the company!
Old Curmudgeon, it certainly makes sense that live testing would be part of the product development process. My guess is that you did discover flaws that could be corrected before the systems shipped.
@Oldetc. I enjoy your responses because I think we both were raised in the old school when engineers actually physically assembled and trouble shot their creations. I like to remind people that Eli Whitney was a blacksmith, before he was an engineer.
To the original poster, congratulations on your tenacity and ability to solve the issue. I do remember when Troybuilt was a gold standard and am sorry to hear how it has slipped, but then again I have had numerous MTD ptoducts that performed well, so just the fact that they now produce Troybuilt would not seem to be the only problem. I always revert back to the position that companies are now almost exclusively run by MBA's rather than someone who actually got their hands dirty on occasion.
"I always revert back to the position that companies are now almost exclusively run by MBA's rather than someone who actually got their hands dirty on occasion."
I would take partial exception to that statement. In my case, I worked for two companies that were owned & headed by "engineers" in their degreed professions. Both companies were VERY successful, and a force in their respective industries. However, I've also worked for two companies that were owned & headed by "engineers" who were GREAT on the "bench", but had no marketing foresight whatsoever, and both companies failed even though their product lines were sold in the mainstream of their respective industries.
I would say that it is rarer than one suspects to find a CEO who not only has the in-depth technical knowledge of a product, but also has the mental "tools" to be able to effectively market the product. Of course, I'm not speaking of a "mpm & pop" type operation where the # of hats worn each day is countless. I'm speaking of a decent sized company where the (technical) CEO guides his Marketing staff in their dutes.
I think there may be a generational chance here, Old Curmudgeon. Two or three decades ago, there were more engineers running tech companies. Since the mid-to-late 1980s, it seems the MBA became king. That means instead of a focus on customers and product, the focus becomes market and financial manipulation.
When your lab is only one scope, one meter, and one homebrew function generator and power supply, the scope is stage center. But this one wasn't working right.
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