John Deere 59" Snow Blower Connection Question

[FredSG]

Hi,

Can someone tell me if all I need to connect my 4310 driveshaft coupler to the gear box on my 59" snow blower is a single cap bolt or hex bolt? I was told I need a key??? Where would a "key" be used or fit in this application? My photo shows the cap screw as mentioned in the manual by the red arrow. What grade cap screw/bolt should this be? Could a sheer bolt/pin be used, but in my case, they break too easily.

My key thread title is a duplicate post but with a different thread title. My apology.

FredSG

 

[CobyRupert]

Is there a shear bolt elsewhere?
You need one somewhere, right?

 

[FredSG]

Coby, I don't understand your reply? Did you understand my posted question? I thought my photo would focus on what I was looking for in the way of an answer?

Thanks for your reply . . .

FredSG

 

[CobyRupert]

I assumed you were referring to a "shaft key". Where the shaft and the coupling each have a square slot in them, at their junction, that a rectangular "key" goes in that joins the two pieces so they spin as one.


Your manual doesn't show a shaft key coupling. Coupler and shaft are locked with a bolt.
What grade bolt? Good question. Does manual list bolt (grade) elsewhere? (A parts list elsewhere?)
If not, we need to make some educated guesses.
Does bolt need to shear to protect the tractor and blower components from breaking when blower jams trying to eat a (say) 2"x4"? Thus my original question.

 

[FredSG]

Coby,

Great post. Thank you. Manual does not list bolt grades. I've been using sheer bolts, but are they too weak in this connecting application? If sheer bolts were OK why doesn't the manual, in the photo I posted, say use a sheer bolt? Why do they mention a cap bolt? And then, back to my original question, what grade of cap bolt would be "safest" to use in this connection, i.e., driveshaft coupler to the gear box on my 59" snow blower?

Thanks again for your post and the illustration. Where did you get that illustration, by the way?

FredSG

 

[CobyRupert]

I googled "shaft key" then clicked on "Images".
You would think that manual would of called bolt grade if it is suppose to be a "sheer bolt" protecting drive line.
...but what/where is the sheer bolt if not here?

I'm not a machinists. There's lots of grades, but I think grade 2, 5 & 8 are (most?) common. Grade 2 sheers easiest and would be "safest" of these 3...if you can get blower started.

 

[radios1]

the shaft may be splined, and the cap bolt merely holds the shaft from falling off. 5/16 seems to be way too small for a shear bolt anyway.. talk to your dealer.. maybe there's a clutch somewhere else that protects against damage.. there might be sheer bolts on the auger of the blower that perform the safety function..

 

[MechE1]

Mine has a key and then a bolt to hold the shaft on. Assume it's the same. It is not a woodruff key. The bolt is fully threaded and has a nylon lock nut. I do not believe this to be a shear bolt.

 

[Zebrafive]

I posted in you other question. JD parts shows a key, P/N M84550. The bolt, P/N 19H1901 is 5/16-18 x 2" Grade 5.

 

[FredSG]

So, finally, got it all figured out. On the photo I posted received clarification from two JD dealers. All that is needed to make that connection secure is a 5/16 x 2" grade 5 cap/hex bolt. There is no key/key way involved in this application or connection. I had been using a sheer bolt which is weaker than the grade 5 cap/hex bolt that should have been used to secure the 4310 driveshaft coupler to the gear box on my 59" snow blower.

Really wish the JD manual for my 59" snow blower was more detailed and gave more information on parts required for fixes.

Thanks to all who contributed to my dilemma.

FredSG