WTF, Japanese Tractor Engineers?

Kinja'd!!! by "JawzX2, Boost Addict. 1.6t, 2.7tt, 4.2t" (jawzx2)
Published 04/20/2017 at 22:19

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STARS: 4


So, I’m rebuilding the leveling link on my Ford (Shibaura) 1720 tractor’s 3-point hitch. The thrust bearing is just a few rusty pebbles instead of balls and a warped, rusty cage, so I needed a new one....

1st) the unit seems quite standard at first, with a 20mm ID and a 40mm OD, nice standard metric bearing size, EXCEPT, instead of using a standard three-piece thrust-bearing it has the races machined into the shaft and bracket instead, and is intended to use oversize balls in an open-cage (like an old-style bicycle head bearing) to fit in there and create the correct mesh for the gears (there’s only about 5mm space). OK, thats a PITA.

Kinja'd!!!

But bearings are cheap, so I’ve got a big three-piece with extra-beefy balls AND a super-thin 2.5mm roller-bearing on order, one of them is bound to fit (with or without shims, as the case my be), or at least be close enough to be better than the bearing-dust that’s in there...

Kinja'd!!!

So, anyway... the main reason the bearing-dust exists is becuase at some point the zerk fitting got broken off.... no problem, I’ll just use an easy-out to remove the busted stud, clean up the threads, and put a new one in (6mmx1 FTW) ...

2nd) wait, no I won’t. Because apparently the Japanese who built this thing made the fucking zerk out of like grade-12 ultra-hardened steel. I literally could not SCRATCH it with any drill bit I had in my kit, and the easy-out wouldn’t grab it because FUCKING ULTRA HARD STEEL. WTF? Isn’t a zerk supposed to be made out of mild steel so that when it INEVITABLY breaks off you can remove it easily? In any case, I gave up. what did I do?

Kinja'd!!!

Next I tried running my 3mm tap down the center of the broken zerk stud so I could then drill out with a 3.5mm bit and run the 4mm tap down, etc etc until we’re back to 6mm. Spoiler: I will be buying a new 3mm tap because HARDEST FUCKING STEEL ON EARTH apparently. I know, it doesn’t even look like I touched that shit! It’s like goddamn armor plate, probably harder.

Kinja'd!!!

I *REALLY* gave up, punched a starter mark on the opposite side and drilled and tapped the cast-iron body. No problem. Bit was still cutting well at the end, and it’s almost 10mm thick. Did I mention I DO NOT have shitty drill bits? I’ll just fill the old stud with some RTV and deal with a PITA to access Zerk on the underside of the mechanism, At least I’ll be able to grease it now.


Replies (5)

Kinja'd!!! "pip bip - choose Corrour" (hhgttg69)
04/21/2017 at 06:00, STARS: 0

quality engineering

;)

Kinja'd!!! "JawzX2, Boost Addict. 1.6t, 2.7tt, 4.2t" (jawzx2)
04/21/2017 at 07:01, STARS: 1

I would have gone with “near-psychotic cost-cutting measures, completely negated by massively overkill materials quality/quantity, not to mention some damn impressive metallurgy.”

Kinja'd!!! "You can tell a Finn but you can't tell him much" (youcantellafinn)
04/21/2017 at 08:11, STARS: 0

Tractor companies are assholes about using proprietary stuff. They want you to have to buy the part from them. I had a spline yoke go to shit on a John Deere. Since they used some goofy metric size and something stupid like 37 splines there is no such thing as finding this yoke somewhere else. So instead of what should have been a $10 yoke I was stuck buying a $750 driveshaft from John Deere.

Kinja'd!!! "Urambo Tauro" (urambotauro)
04/21/2017 at 12:23, STARS: 0

The zerks are hardened? That does seem strange.

But come to think of it, I had to screw in some fittings into my new tie-rods before installation, and the holes in the joints weren’t threaded. Maybe the fittings are hardened so that they can cut their own threads?

Kinja'd!!! "JawzX2, Boost Addict. 1.6t, 2.7tt, 4.2t" (jawzx2)
04/21/2017 at 21:20, STARS: 0

that was my thought too. They’re still jerks.