DMM-60 Drive shaft to tranny input shaft roll pin (spring pin) gone

[malk315]

As the subject says, I managed to lose the 2 x "spring pins" (looks like one goes inside the other as shown in the exploded view of the deck in the manual) that keeps the drive shaft coupled (and takes the torque) to the input shaft on the MMM transmission.

All it took was throttling down for the pins to shear or whatever -- they are just gone, I can't find them anywhere... so I'm thinking they also might have just worked their way out although it's too coincicental that it would happen when throttling down... they probably were sheered.

So... Anyone have any idea what size "spring pins" (roll pins I think are the same thing) that are the following part #s?

05411-00840 (outer "larger" spring pin)
05411-00540 (inner "smaller" spring pin)


Interestingly from tractorsmart.com (kubota parts), the following all come up as spring pins:

05411-00540 (kioti and kubota)
05411-00840 (kioti and kubota)
05411-00536 (kubota)
05411-00650 (kubota)

There must be standard far-eastern I'm guessing roll pin supplier they use. Would love to know what sizes all of those (and material for proper sheering force required to sheer them) are to just get them from an auto-parts or hardware place...

Any info from you guys would appreciated. Obviously a sheered roll pin is a new thing for me and after this, I'll make sure I have a supply of them on hand as I'm thinking the chance of it happening again is large (one blade hitting a rock, dirt, stick, whatever).

 

[malk315]

Update -

I found some steel spring pins at the local hardware store.

5/16" fits snug into the shaft, but I can push it in w/ my fingers -- even w/ a smaller one inserted into the 5/16" one that required a little hammer tapping to get it in. So w/ both in there, I can push it out w/ my thumb applying a decent amount of pressure -- I'm not convinced it would stay in there properly under normal use.

Next size up is 3/8" which seems way too big to me... I could be wrong as I haven't dealt w/ roll pins on anything I own to date.

A 5/16" roll pin is 7.938 mm. So perhaps a genuine 8 mm roll pin would work (although 6/100ths of a millimeter isn't much -- but maybe w/ two of them exerting pressure over all that area, they'll stay in and require hammer taps to get them in).

I've also seen just from googling around that 8.5mm roll pins do exist... so that's not out of the question.

A 3/8" pin is about 9.5 mm which is too big. It is possible a 9mm pin would work and those do exist too.

My problem is, I'm not going to acquire anything that will allow me to continue to work today. I also want to verify the correct pins to use and just use them. I can't stand screwing around w/ the wrong stuff -- I like to just use the right thing and be done w/ it.

I called Wallace in PA to see if they could gleen from parts books the right size pins (to my surprise they are open on sunday unlike every tractor dealer of any type w/in 100 miles of me!). They were really nice and I appreciate them checking, but they couldn't tell. He was telling me the deck is actually italian made (Kioti doesn't carry them anymore -- they have a totally different style MMM now). I do really like the way it cuts -- much better than my old garden tractor.

Anyway -- I'll call my dealer tomorrow to find out what I need (I hope).

One other thing -- I compared the assortment of roll pins I grabbed today (which was a whole range of them since I needed one that fit inside the other) with the roll pins used that to hold the guide wheel shafts on the front of the deck in place. It was obvious none of my english sized roll pins match up in size to those on the guide wheel shafts. One was too bing and the other too small and there were no other in-between sizes in the assortment from the hardware store. So I'm quite certain the pins used to hold the guide wheels on are metric. Really wish I had a decent micrometer...

 

[malk315]

Well I learned some more on this:

Ronnie from tractorsmart.com revealed that these 05411 spring pin numbers map as follows:

05411-00840 should be an 8mm diameter x 40 mm length (about 1.6 inches)
05411-00540 should be a 5mm diameter x 40 mm length

This jives pretty well w/ my standard size ones I was able to get from local sources -- the 5/16" x 2" is very close to 8mm diameter. The 3/16" x 2" is very close to the 5mm diameter.

I've got the genuine kioti ones on order from my dealer.

I also ordered a few of the above from tractorsmart.
Lastly, I blind-ordered and am happy to find I'm probably correct some 8mm and 5mm x ~ 50mm long steel spring pins from McMaster/Carr who usually turn around orders for our machine shop by next day.

So hopefully by mid-week I'll back up and running.

I'm just posting all of this info in hopes of helping fellow TBNers who might run into the same problem. I could try to wire up the 5/16" pin w/ 3/16" inner pin on the shaft or try to force the 3/8" one in there, but I'd rather use the correct, metric stuff.

I tried all over the place to find loose or blister packs of metric spring pins and no-one has them.

 

[malk315]

After ordering from mcmaster, tractorsmart, and my dealer monday, the pins arrived at the dealer today.

Sure enough they are 8mm diameter x 40 mm length and 5 mm diameter x 40mm length.

So the 05411-00DLL part #'s are spring pins where D is diameter in mm and LL is length in mm for both Kioti and Kubota.

I tapped the 8mm one right into the shaft followed by the 5mm one into the 8mm one. Since I don't have a punch, I rounded over the end a bit, but got both pins home where they belong. This made the yoke mate to the mower deck drive shaft nice and tight (there was a small bit of play w/o the pin in there that had me a little concerned).

Fired it up and mowed the lawn no problem this evening. Inspection after mowing revealed the pins don't appear to have moved anywhere.

I will certainly be a bit more careful to make sure the PTO is off before releasing the clutch too quickly (I'm pretty sure that one time I let the clutch out quickly w/o realizing the mid-pto was engaged is what did my original set of pins in).

I've got 10 of each on-hand now. Plus a bunch of extras from the other suppliers (the mcmaster ones are a bit too long at 55 and 50mm each, but should be useable if needed)

Hopefully the next thing is to change the gear oil on the deck transmission (not at 50 hours yet since I only mowed half a season last year) and then I should be good for a while (just had the 50 hour service done on the tractor).

So far the issues w/ my machine have only been problems that can happen w/ any brand of tractor.

Hoping this thread (feeling kindof alone here -- no-one replied but myself!!!) will be useful to others if similar problems arise w/ other PTO setups that use spring pins instead of sheer pins.

 

[TractorLegend]

I just don't think that many peeps (here) opted for the mid mount mower.
That may be why you feel like you are talking to yourself.
I considered one since I was upgrading from a garden tractor- and on my particular terrain I could forsee where being able to back into spots with the rear finish mower would be a benefit. Too, if I remember correctly, the mid mount mower was more money.

 

[BTDT]

Good luck on your repairs. And keep posting. Folks may not respond, but they are looking. I read a lot on TBN, majority of it doesn't pertain to my brand of tractor, but it's all good information. You have probably helped folks by posting.

 

[tombehringer]

I'm having all kinds of issues with pins on my Kubota B7100 and it seems metric is the only way. Also I didn't realize there could be 2 different pin sizes.. inner and outer as I was stumped as to why it was hourglass shaped but I think your post answered that. There are 2 .. smaller in the middle and larger at the outside. It's Sunday so I'll wait and call my Kubota dealer tomorrow. Tx for the post. Tom