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This fellow points out engineering stupidity 7

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Happened to me. Yes, there is no means of lubricating the bearings. The pulley is two stampings rivetted together, enclosing the bearing. As mine is a thousand years old there are no spares, so I had to drill all the rivets out of the pulley to take it apart, put a new bearing in, and then rivet the pulley back together. It's lasted one season so far!

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
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I've had similar issues on my 2001 Deere but fortunately they're common enough that not only does Deere still supply replacement parts, but also the aftermarket at a more comfortable price point. If I can eke out another 6 seasons with this machine, that will do, then I'll be ready to retire and move somewhere away from this midwest hellhole and leave the riding mower (and maybe large scale mowing altogether) behind.

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz
 
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My Toro might be a cheap assembly of plastic and tin but it is fairly simple, built with disassembly/maintenance in mind, and Toro does give free access to their maintenance manuals online which show how to replace individual spindle bearings. It only took ~30 mins total to remove the deck, blades, pulleys, and spindle shafts. I discovered one of the spindles' lower bearings seized and after a few hours searching online then in person at various box, ag, and other stores, could only find a non-sealed version of the bearing I needed locally. Given lousy weather reports and an inability to source bearings until today (Monday), I decided to lube and run the seized bearing. I carefully popped the seal out with my knife, blasted the rusty ball bearings with brake cleaner then penetrating oil, and carefully worked everything until freely rotating. I then relubed it with grease, reinstalled the seal, and reassembled the deck. I am sure the seal has lost some of its effectiveness but the bearing didn't seize, sounds decent actually, and our 1.5 acres was mowed so I'm calling it a win.
 
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enginesrus said:
It takes those stupid mechanics to figure out how to make something work that the stupid engineers couldn't figure out.
Click to expand...

Guess who figured out a fix for the dreaded 996 IMS problem?

Engineers.

At this point, man, everyone gets your schtick. We engineers are all morons, everything was better in 1949, we should all go back to acre sized drafting rooms full of dudes wearing skinny ties and smoking lucky strikes all day while they draw pencil on vellum.

We get it. We're all stupid. You know better. You know everything.

There. Does that satisfy you enough to stop posting this nonsense?
 
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SwinnyGG, No not all. Some are very good at what they do.
 
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Sturgeon's law is the adage that “ninety percent of everything is crap”. This suggests that, in general, the vast majority of the works that are produced in any given field are likely to be of low quality.

 
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To me, the stupidity in that design is it even having a grease fitting. That was probably required by marketing. Properly chosen sealed bearings last a VERY long time in a non-commercial use lawnmower deck.
 
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Especially when modern bearings use polyurea grease which I have never seen sold at an auto parts or DIY store.
 
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The incompatibility of grease systems makes me long for oilers. No thickeners means nothing to harden and block the bearings. Even with compatible greases, oil loss still leaves thickener that is difficult to remove.

Tugboat - Gotta look in the farm department:
 
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Screenshot_20210520-083257_gx8wzp.png
 
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I just pointed out it's available from places people currently shop. Online stores count. It's not unfindable. It may be better that way as mixing greases is a great way for those with no background in lubrication to destroy equipment and grabbing a tube from the shelf will do that.

In a tangentially lubrication-related case, a chain was sued over the sale of automotive oil that destroyed engines. It included SAE 30, SAE 10W-30, SAE 10W-40 weight oil. The problem being that no car since around 1930 had an engine designed for SAE 30 oil, and no cars after 1988 would use the other two. How-so? Because the fine print said "SA Specification" (30) and "SF Specification" (10W-30 and 10W-40).
For the typical consumer, lubrication is a minefield. For them grease is grease and oil is oil.
 
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That's a rather BS lawsuit. I doubt any newer engine would suffer catastrophic damage using those oils. Maybe an earlier long term failure, but that would mean using that oil it's entire life and probably owning it from new to well over 100k miles before seeing the failure. If you owned it used, then how can you determine it was the oil vs a previous owners other abuse?
 
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That was an interesting video. It wasn't clear why the bearing he showed us was "gritty" but I have to wonder if there isn't an application or bearing quality problem rather than a lack of lubrication. The grease inside didn't look terrible and I didn't notice any signs of overheating. It's a slow-speed application but could have high shock loading and possible misalignment.

I worked for a highly-regarded UK dynamometer manufacturer right out of university and learned that grease content and quality is critical in high-speed applications. The bearings specified were the sealed type in most applications or open and oil-mist lubed in very high speed applications such as when connected to gas turbines. The policy of allowing customers to lube bearings via grease fittings was deemed to be the reason for failures. Having no knowledge of this technology I absorbed everything I was told.

At a job decades later I was tasked to fix an issue with our industrial slurry pump product (used in mining) which frequently had bearing failures. The existing manufacturing docs called out for the two sealed bearings to have one seal removed at assembly and the OEM grease washed out and replaced to 100% fill with with a "marine-grade" grease. Apparently there was a concern that water could enter the bearing and somehow this marine grease would allow it to survive. They were assembled much as they were in the lawn mower situation but with grease fittings near each raceway.

Needless to say I ECN'ed the docs to retain the bearing's OEM seals and grease fill as supplied and eliminated the grease fitting. Sure enough the relevant marketing dude steps in (who had originally conceived the design) and demands to know why I'm changing it, because "obviously" the lube needed to be refreshed.
 
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KiwiME - you left out what the results of the changes were. I'm assuming better life????
 
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