Shear Bolt Broke On New Deck. PTO Shaft & Gear Box Holes Don't Align.

[RickB]

If it's a slip-clutch driveline is the grade 8 vs grade 2 shear bolt a backup in case the clutch doesn't slip then? Clutch doesn't seem to have spared the '8' bolt any grief this time.

btw, I have the type ptsg showed on my Betstco flail mower and don't trust the slip clutch on the KK tiller. Time to rethink whether I'll use both or just the one I don't have to recheck every season.

My answer is in post #11 above. Most manufacturers use a splines or keyed connection between a slip clutch and gearbox. This one doesn't and the OP gets to deal with it.

 

[Have tractor did travel]

Thank each of you for encouragement to service slip clutch. My bush hog helped clean up a mobile home park in North Carolina about 7 years ago, then sat in Mobile doing nothing. Now it's rehabilitating pastures in Virginia, and I never serviced the slip clutch. I'll get on it tomorrow.

 

[FunkeeMunkee]

Thank you to everyone who has replied.
- The cutter is new, new, new. Not frozen, not rusted.
- The cutter has been used 6 times (went and looked at my victory photos). It did not sit for 8 months before being used. This is not a matter of one years worth of regular use and moderated workload. This is flat ground, weeds and struggling grass for a total of 20 - 30 minutes each time.
- I didn't get a manual. Nor did any of the JD professionals involved ever bother to say - "oh by the way - we chose to replace your old cutter that utilized shear bolt protection with a cutter that utilizes a slips clutch." OR " If you let it sit or use it hard - or a year has passed, the slip clutch needs maintenance". Is it unrealistic to expect a new/never used cutter with a slip clutch to be functional for at least the honeymoon period?
- The photos are labeled correctly.

It always helps when the professionals use the correct terminology. When I ordered the grade 8 bolt I was told it was a shear bolt by the parts guy. Hence the confusion when the service guy mentioned slip clutch. Today I looked much more closely. The PTO shaft and the Gearbox are shrouded in tighly fitted, shiny, slick black plastic from one end to the other so it's hard to tell what's going on when your only view is from 2 awkwardly placed access holes blocked by braces. Many of you win a chicken dinner. There is a slip clutch obscured by "all the bubble wrap".

I used a fairly rugged but thin fence spike to see if I could get any movement and to my surprise there was with some exploratory pressure. It didn't make the holes line up completely but there was certainly an improvement. I felt like if I had something a little more appropriate for the task than the spike, I might be able to get it just right. Until I just read many of your answers just now, I was going to just go pick up the Grade 8 Bolt when it came in and install it myself. Discovering that my cutter has a slip clutch, reading comments here about annual maintenance and so on, I am just going to load the whole kit and kaboodle up and have the dealer "deal" with it. I don't have the patience to try to remove all the plastic and attempt to do the require slip clutch adjustment/maintenance following some you tube channel tutorial while sitting out in the hot Florida sun (or daily thunderstorm).

I really do appreciate your advice and suggestions.

 

[ning]

If this was my equipment, I'd get a positive ID on the slip clutch before putting a grade 8 bolt back into place... and then I'd get that clutch to spin.

Given that you're taking it back to the dealer to have them do it, tell them that you want to see the slip clutch that they say is on it so that you can service it in the future.

 

[RustyA]

Perhaps the humidity caused lot rot of the slip clutch while it was sitting waiting to be sold. Might be rusted together...

 

[ruffdog]

I have seen manuals for new rotary cutters stuck to the bottom of the deck in a plastic pouch. Could it still be there?

 

[cathy liebchen]

Thank you to everyone who has replied.
- The cutter is new, new, new. Not frozen, not rusted.
- The cutter has been used 6 times (went and looked at my victory photos). It did not sit for 8 months before being used. This is not a matter of one years worth of regular use and moderated workload. This is flat ground, weeds and struggling grass for a total of 20 - 30 minutes each time.
- I didn't get a manual. Nor did any of the JD professionals involved ever bother to say - "oh by the way - we chose to replace your old cutter that utilized shear bolt protection with a cutter that utilizes a slips clutch." OR " If you let it sit or use it hard - or a year has passed, the slip clutch needs maintenance". Is it unrealistic to expect a new/never used cutter with a slip clutch to be functional for at least the honeymoon period?
- The photos are labeled correctly.

It always helps when the professionals use the correct terminology. When I ordered the grade 8 bolt I was told it was a shear bolt by the parts guy. Hence the confusion when the service guy mentioned slip clutch. Today I looked much more closely. The PTO shaft and the Gearbox are shrouded in tighly fitted, shiny, slick black plastic from one end to the other so it's hard to tell what's going on when your only view is from 2 awkwardly placed access holes blocked by braces. Many of you win a chicken dinner. There is a slip clutch obscured by "all the bubble wrap".

I used a fairly rugged but thin fence spike to see if I could get any movement and to my surprise there was with some exploratory pressure. It didn't make the holes line up completely but there was certainly an improvement. I felt like if I had something a little more appropriate for the task than the spike, I might be able to get it just right. Until I just read many of your answers just now, I was going to just go pick up the Grade 8 Bolt when it came in and install it myself. Discovering that my cutter has a slip clutch, reading comments here about annual maintenance and so on, I am just going to load the whole kit and kaboodle up and have the dealer "deal" with it. I don't have the patience to try to remove all the plastic and attempt to do the require slip clutch adjustment/maintenance following some you tube channel tutorial while sitting out in the hot Florida sun (or daily thunderstorm).

I really do appreciate your advice and suggestions.

The plastic guards are easy to remove and the slip clutch is easy to service. If you don’t have patience to do it just pay the dealer to do it

 

[Williy]

I use a punch to line up holes as its tapered and
works better than a nail, bolt etc.

willy

 

[PerroneMM]

Just slow down a little bit when you're in that tall grass it's been a while you'll be okay but a new share boat in if it's front to back that you're worried about not lining up just move the shaft a little bit it'll line up

 

[kipgary]

An aligning rod might take care of it. Otherwise, have you tried working a Philips screw driver with a shaft slightly smaller than the bolt into to hole to see if you can align them that way?

 

[slider909]

Use a awl to align it. I have to when mine shears.

 

[TractorGuy]

My guess is the hole was drilled in the gearbox shaft at an angle. Try rotating the yoke 180* and see if the holes will line up. You might need a large tapered punch to get the holes lined up.

Also look at the front of the yoke and make sure the C-clip hasn't come off and got gone. When you slide the yoke all the way towards the gearbox you should see a groove with a C-clip in the end of the shaft. If it just has the groove you need to replace the missing clip.

 

[mikedodd]

It's hard to tell from the small images, but it looks to me like the gearbox hole isn't clear. Maybe it has part of the broken shear bolt stuck to the side. I have a couple of suggestions:

1. Does the PTO connector slide on the gearbox shaft? To me, that's the first thing to ensure, or else the holes will never align.

2. Use a nail set or other hardened tool to tap on whatever is occluding the hole, to see if you can break it loose.

3. Use a coarse round file to see if you can file away some or all of whatever is occluding the hole. You need to get that gearbox shaft hole completely cleared.

4. Once the gearbox shaft hole is clear, can you insert the new shear bolt? If not, as someone else suggested, tap a tapered round tool into the hole to slide the PTO connector until the holes align. I've attached a photo of a Stanley tapered punch I've used to align holes, but it's just over 1/2" diameter. Maybe you could insert it, then hammer it sideways to move the PTO connector. Or, use any tapered tool, such as the masonry drill in the photo. Insert the handle into the hold until the tapered end hits, then hammer on the tapered end. Or grind a taper on the end of any piece of steel 3/4" diameter or larger, and hammer that into the holes.

I hope this helps.

--- Mike

 

[Martin Roper]

To me a grade 8 is a pretty standard shear bolt, some times shear pins just want to be replaced. The fact that these holes are not lining up on either 180 degree suggests to me that they haven't been since new so putting the pin under more pressure (as it seems unlikely to be the pressure of work that broke it). I would re-drill the hole, I know that will affect the warranty but you have already proved it is not up to much anyway and you have a machine you can not use at the moment.

 

[bearthebruce]

We can all stop... The OP said:

Thank you to everyone who has replied.

Discovering that my cutter has a slip clutch, reading comments here about annual maintenance and so on, I am just going to load the whole kit and kaboodle up and have the dealer "deal" with it. I don't have the patience to try to remove all the plastic and attempt to do the require slip clutch adjustment/maintenance following some you tube channel tutorial while sitting out in the hot Florida sun (or daily thunderstorm).

 

[TractorGuy]

I haven't seen a picture of a slip clutch. Why would the gearbox have a smooth shaft with a through bolt if it has a slip clutch?

 

[dpgood1]

I haven't seen a picture of said slip clutch.

 

[the old grind]

11 through 17

 

[TractorGuy]

I haven't seen photographic evidence that the OP's driveshaft has a slip clutch. All he has posted is close ups of the yoke hole.

A lot of mowers will list a slip clutch shaft as an option.

His mower should have a plastic document tube with the manual inside.

As far as expecting a dealer to service a slip clutch prior to delivery you are dreaming. The only implement I have with a slip clutch type shaft had the clutch bolts tightened All the way down. All the parts were rusted together and a cup of water came out when I tapped them apart with a hammer. I had to take it all apart and sand the rust off of all the parts.

 

[TractorTenderfoot]

I am truly a tractor tenderfoot, but with some machinery experience. The bolt that sheared may not be a "Shear Bolt," per se, but it is a bolt, and it did shear. I am working a slip clutch issue on a different thread based on a quote from my Frontier RC2060 manual.
My Frontier RC2060 manual has this quote:
"Slip Clutch Operational Check"
"After the implement has been stored for thirty days or more, perform the following operational check."

It goes on to describe how to loosen the bolts on the slip clutch and then to operate the PTO to make sure that the slip clutch . . . slips to protect the rest of the drive train. In my case, it does not slip (it sat for a long time prior to my ownership) and I'm in the process of figuring out how to get it free. The best advice I've gotten on this forum to free it is that while the bolts on the slip clutch are loosened, to engage the PTO back into heavy grass that would presumably cause the clutch to slip, then adjust the bolts as described in my manual and go about my mowing business.

Questions: Is it possible, that you engaged the PTO while at full-rated engine RPM, rather than engaging it at idle and then ramping up the RPM to full speed? I have heard anecdotally that such can shear bolts.

Why didn't your new mower come with a manual?

There are quite a few minor maintenance issues associated with tractoring, and you may want to consider getting familiar with them to save many trailer trips to the dealer.