More M59 repair fun.

[Billrog]

One thing I think was hard one my tractor loader pins was carrying a heavy load over ruff terrain going to fast with the bucket bouncy up and down. I know for sure it was hard on the front wheel bearings and seals because I was replacing them every 4 years.

 

[5030]

I do that all the time, traverse rough terrain (hayfields) with a 4x5 round bale or two on the front spears and one on the back spear. Never had issue one with loader, pins or seals. Tractors are 10 years old now.

I need one on the back with 2 on the front or else the backend is way too light. They only weight about 1300 pounds each......

 

[SPYDERLK]

One thing I think was hard one my tractor loader pins was carrying a heavy load over ruff terrain going to fast with the bucket bouncy up and down. I know for sure it was hard on the front wheel bearings and seals because I was replacing them every 4 years.

I do that all the time, traverse rough terrain (hayfields) with a 4x5 round bale or two on the front spears and one on the back spear. Never had issue one with loader, pins or seals. Tractors are 10 years old now.

I need one on the back with 2 on the front or else the backend is way too light. They only weight about 1300 pounds each......

You will get nowhere near the pin forces carrying stuf that you get on a push-lift on ground engaged objects. Thats assuming 4wd, and that you use it to the traction limit on a prudently counter weighted tractor.

 

[Billrog]

Spiderlk that may be very possible the tractor I had was only 3,000 lbs. 4 WD and I also used it pushing out hundreds of small fir trees. But loading logs that lifted the back end up even with counter weight did the front wheel bearings in. So I started using bigger equipment for the large logs & that ended my front seal bearing problem. None of the pins on the Case tractor were drilled but it looks like they are on the Kioti so I'll keep an eye on them after I get a few more 100 hrs. on it.

 

[SPYDERLK]

Spiderlk that may be very possible the tractor I had was only 3,000 lbs. 4 WD and I also used it pushing out hundreds of small fir trees. But loading logs that lifted the back end up even with counter weight did the front wheel bearings in. So I started using bigger equipment for the large logs & that ended my front seal bearing problem. None of the pins on the Case tractor were drilled but it looks like they are on the Kioti so I'll keep an eye on them after I get a few more 100 hrs. on it.

The ones in the bucket circuit are the most susceptible. Take a look at what happens when, valve centered, you push with the bucket angled down say 20 degrees. ... Now, imagine a short pause to lift then resume the push. - Then pause and curl and push-lift to bring it out. Theres a lot of prying pin against pin.

,,,,,,,,,The 7520 is kind of a worst case tho. A big heavy tractor with fully loaded AGs ... And the pins are a little small.

 

[rScotty]

The 7520 is kind of a worst case tho. A big heavy tractor with fully loaded AGs ... And the pins are a little small.

How small is small? What diameter are those 7520 pins? What kind of loading do they rate for at the forward pins? I got curious so went out and looked at some of our other similar lift tractors. Back in message #56, 5030 pointed out that these tractors we are talking about are all roughly the same size - all big tractors with pin loading at the bucket in the 4000 lb range....give or take a thousand pounds. That fits the M59 pretty much exactly (4000# pin load spec for fairly large 1.375" diam. pins).

Below are pictures of a couple more tractors to ponder:

The very old JD530 has had these same drilled pins without wear or breakage since 1958! and we've certainly beat it extremely hard in every way. The 530 pins are roughly the same design as we've been discussing but with some slop & even less metal out on the "ears". Pins are 1" center-drilled pins made more or less like the ones that failed on Hersheyfarm's Kubota - and rated even higher for bucket and pin loading. I didn't pull one, but they have to be cross drilled and probably center-grooved as well. They ride in a piece of what looks like 1 3/8" tubing welded inside of the hollow lift arms. So that gives us more or less the same design but with even more flexure and using a smaller pin...and without problems. BTW, the JD530 is only 30 hp, but is quite a heavy tractor. Fitted out as ours is with an implement, it would go 7500/8000 lbs. Not as heavy as the M59, but close.

Next is the JD310SG - known world-wide as one tough construction machine. 90/100 HP and 16,000+ lbs. I have no idea what they are rated for...but it has to be lots. Just guessing, it could be double what an Ag loader is spec'd at. Not heard of a 310 breaking pins, and look at that pivot....it's completely different. There's a full 2" diameter pin but it's cantilevered with no outboard support at all. Not drilled in any way either, and the zerk is on the outer part - not in the pin.

I wonder what steel JD uses? Is that the answer?
rScotty

 

[5030]

Knowing JD like I do, lowest priced supplier.

 

[SPYDERLK]

How small is small? What diameter are those 7520 pins? What kind of loading do they rate for at the forward pins? I got curious so went out and looked at some of our other similar lift tractors. Back in message #56, 5030 pointed out that these tractors we are talking about are all roughly the same size - all big tractors with pin loading at the bucket in the 4000 lb range....give or take a thousand pounds. That fits the M59 pretty much exactly (4000# pin load spec for fairly large 1.375" diam. pins).

Below are pictures of a couple more tractors to ponder:

The very old JD530 has had these same drilled pins without wear or breakage since 1958! and we've certainly beat it extremely hard in every way. The 530 pins are roughly the same design as we've been discussing but with some slop & even less metal out on the "ears". Pins are 1" center-drilled pins made more or less like the ones that failed on Hersheyfarm's Kubota - and rated even higher for bucket and pin loading. I didn't pull one, but they have to be cross drilled and probably center-grooved as well. They ride in a piece of what looks like 1 3/8" tubing welded inside of the hollow lift arms. So that gives us more or less the same design but with even more flexure and using a smaller pin...and without problems. BTW, the JD530 is only 30 hp, but is quite a heavy tractor. Fitted out as ours is with an implement, it would go 7500/8000 lbs. Not as heavy as the M59, but close.

Next is the JD310SG - known world-wide as one tough construction machine. 90/100 HP and 16,000+ lbs. I have no idea what they are rated for...but it has to be lots. Just guessing, it could be double what an Ag loader is spec'd at. Not heard of a 310 breaking pins, and look at that pivot....it's completely different. There's a full 2" diameter pin but it's cantilevered with no outboard support at all. Not drilled in any way either, and the zerk is on the outer part - not in the pin.

I wonder what steel JD uses? Is that the answer?
rScotty

View attachment 464438View attachment 464437View attachment 464436View attachment 464435

View attachment 464439

,,,,,,,,,The size of the pins is 1.125, stated awhile back. - - The forces pins in the curl circuit see is many times the lift capacity of the loader. ... Take tractor weight, loader, counterweight and ballast, and lift capacity [over 5K for the 7520 at low height] and add together. This gives the conservative push force figure with AGs. - - For the 7520 this amounts to about 17,000#. -- Then theres some multiplication of this figure in the curl circuit when 1 pin location pries against the other during the 17K push. I would guess my pins see over 20K on occasion where load is offset a lot to one side or the other.

I am surprised that 1.375 pins on the M59 would fail. Kubot has done an extraordinarily bad job on that setup.

,,,,, The steel, and the finesse used in finishing/optimizing the stress profile can make a huge difference.

 

[rScotty]

Knowing JD like I do, lowest priced supplier.

Yeah, I agree....although I still am hopeful that JD is better than the average.

In my 50 years of working in industry I've seen the manufacturing transition go from making parts "in house" - where quality was carefully monitored - to where it is now when outside suppliers build most components and compete for lowest price.

Looked at globally, that's probably an advantage, but it sure hasn't been as good for the workers here.
rScotty

 

[TBarD]

Yikes - Just saw this thread. Thanks for the heads up, I may replace some loader pins at probably the 1000 hour mark, just to be safe.

For reference here is a pic of a warn pin from the front quick attach assembly. When I bought the tractor at 250 hours, the previous owner had torqued and warped the quick attach and I had to pull 4 pins and replace it. The pin shown was badly warn due to things being out of alignment. In any case, this illustrates the construction of the pin. It is drilled for grease from one side, and there is a single cross drill as shown. I don't recall any longer, but I don't remember any damage to the pin sleeve, so it may be that the pins are intentionally of a softer steel than the sleeve.