Question on Yanmar RS1200 tiller

   / Question on Yanmar RS1200 tiller #1  

flusher

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Getting old. Sold the ranch. Sold the tractors. Moved back to the city.
I bought an RS1200 tiller last month and am getting ready to use it. Don't have a manual showing the parts so I'm feeling my way to hooking it up to my Kubota B7510HST.

Did a TBN search on this tiller and found an old thread regarding shear bolts

Tiller shear bolt.
#273886 - 06/01/03 09:30 PM
Tiller shear bolt

According to this thread, there's a shear pin on the tine shaft. Here's the quote:

"Brett,
The bolt is on the outout shaft of the chain case right next to where the tines are. I took the bolt to work and tested it on the Rockwell, a grade 3 bolt was almost the same hardness. I put it in and tilled some more tonight. I do like things proper so that is why I'm looking for the correct pin. It is a RS1200 Yanmar tiller.

Rich"

I checked my tiller and found three bolts that connect the chain drive to the tine shaft (see attachment).

Question: are these three bolts supposed to function as shear bolts for this tiller?

BTW, I'm planning to install a slip clutch since I'm a belt and suspenders type. Will have to make the necessary mods to the 3PH parts on the tiller to accommodate the slip clutch.
 

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   / Question on Yanmar RS1200 tiller #2  
</font><font color="blue" class="small">( are these three bolts supposed to function as shear bolts )</font>

No. Look at the PTO shaft between the tractor and tiller and either on that shaft near the tiller or through the tiller input shaft itself.
 
   / Question on Yanmar RS1200 tiller
  • Thread Starter
#3  
The shaft on the tiller has a hole drilled through it where a shear bolt might be installed. But that shaft is splined, not smooth like, for example, the shaft on the gearbox of my KK brush hog which is set up for a shear pin. This makes me think that the tiller shaft is not designed to handle a shear pin.


That's why I did the TBN search and found that thread I referenced in my earlier post which seems to say that the RS1200 has a shear pin somewhere on the tine shaft of the tiller. I checked the tine shaft for anything that looked like a shear bolt and the only things I found are the three bolts shown in the attachment.

The PTO shaft that I got with the RS1200 has splined female connnections on both ends. This makes me think that this tiller is not set up for a shear pin in the implement end of the PTO shaft.
 
   / Question on Yanmar RS1200 tiller #4  
Ray, I'm not familiar with that tiller, so I think you can ignore my previous post. That one is obviously different from any I've used or looked at. I still don't think it would be those 3 bolts; I would sure expect it to only be one somewhere, but I could be wrong even about that.
 
   / Question on Yanmar RS1200 tiller
  • Thread Starter
#5  
Bird

I agree with you. Hard to believe that Yanmar would use 3 shear pins on that tiller.

That said, I'm still wondering what they were talking about in that old thread I cited in my initial post. Very confusing.
 
   / Question on Yanmar RS1200 tiller #7  
my RS1400 seems to be like yours. I dont have a shear bolt either, if the tiller catches hard ground or a rock, it will push the tractor.. I will be installing a slip clutch soon.
 
   / Question on Yanmar RS1200 tiller
  • Thread Starter
#8  
Or mess up the PTO gears in your tractor. That's why I'm doing what you are, installing a slip clutch.

Looks like I'll have to weld 6-8" extensions on the tiller lower 3PH pin support to accommodate the slip clutch.

The Yanmar PTO shaft for the tiller is about 24" long when set at the half-way point and this is nearly the same as the separation between the splined shafts on the tractor and tiller when hanging on the 3PH. No room for the slip clutch without welding extensions.
 
   / Question on Yanmar RS1200 tiller #9  
Yep, I plan to extend mine out far enough to use a newer style shaft as well.. The key is not to get it too far out as so it would lighten the front end... Weights might be a nescesity as well...Wonder if anyone has already done this and might have pictures and dimensions???? /forums/images/graemlins/grin.gif
 
   / Question on Yanmar RS1200 tiller
  • Thread Starter
#10  
Front end weights. Another good use for the LA302 FEL carrying a bucket load of road base gravel.
 
 
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