G5200 - Go bang- Saw light at the end of the tunnel, WAIT, MASSIVE FAIL

[bevis]

Please remember I'm no tractor mechanic and this is my first Kubota and first diesel lawn tractor so I'm at a disadvantage and need you help.

So i bought a used hard G5200 and started giving it some love.
Buying lots O parts that it needed, sandblasting wheels, repaint wheels and new tires. New deck wheels and fabbed up new deck wheel shafts. new battery ( finding one that fits is no easy task ), fix crazy wiring that had been butchered, new bearings in the front wheels, changed all fluids / all filters / bleed fuel system. Its on jack stands the entire time. I have started this tractor up on the jack stands a multitude of times. starts effortlessly every time and does not smoke. purrs like a kitten. THEN, i find out that there is a screen filter in the tranny sump that i didn't know about. Go to dealer and get an eyeball of what the screen filter looks like and buy some O rings so i can pull it and clean it. UG now i gotta drain the hydro fluid again. Oh well, here we go. i pull the screen and it looks pretty good other then a couple of small metal pieces. I clean the screen in a quart paint cup of lacquer thinner. i stick a magnet inside the tranny sump and get any more metal out that i can. nothing big, just a few little pieces. reassemble and refill the tranny fluid. then i finish fabbing up the deck wheel shafts and install all 3 front deck wheels.

I SEE LIGHT AT THE END OF THIS 3 WEEK LONG WAIT BUT, WAIT FOR IT !

tractor is supported on jack stands in the front and on a floor jack not jack stands in the rear just in case rear axels try to turn.

Hit key and tractor sounds like its grunting a little and it fires immediately, then
BANG and parts fly across the garage. I yank the fuel kill to stop the insanity.
Im standing there in complete disbelief and dismay. I know nothing about Kubotas or diesel tractor other than this G5200 adventure. It has sheared both bolts off flush where the shaft from the crank meets up to the front of the tranny pump where the tranny cooling fan is. I find both sheared bolts and both spacer bushings in various places in the garage.

The tranny pump turns freely by hand. the rear wheels both turn freely by hand.
obviously the motor runs.
What the hell did i do wrong ? ? ? ? ? ? ? ? ? ? ? ?

Bear in mind it has started up and ran fine for more than 30 mins when i was testing if it was going to overheat and been started MANY times in the last 3 weeks for testing . EVERY SINGLE time to perfection.

It appears that joint at the crank output shaft and the tranny input is a built in failure point for a safety reason as it feels like the crank output shaft flange is made out of some sort of fiber material.

Was the tranny Hydro locked via air in the system ?
The banjo bolt has a hole drilled through it but it rides in a channel so if its not lined up perfectly with the line coming to it, it still flows fluid. Is it possible that caused the kaboom ?
Im really confused as to why this happened.

Heres the big question. Does anyone know if that pump hub comes off without taking the pump out so i can get it on the bench and get those 2 sheared bolts out of the hub and order 2 new bolts. OF COURSE they are sheared off flush on the crank flange side so you can't get a grip on them for removal. And i guess I'm going to need a new crank output shaft flange that interfaces with the pump hub.

In another pic of the right side of the deck there is a spring and lever of hanging down that has come loose from somewhere and i can't figure out where is goes for the life of me. Could this have anything to do with the boom ? Does anyone know what this spring and link rod is for and where it goes ?

ANY help is going to be appreciated and please help my pea brain figure out why this happened so i don't fix it only to hear it go boom again.

 

[bevis]

more pix of the sheared bolts / spacers bushings and spring and link rod on the right side of the frame that i can't figure out where it goes.

 

[CountryBumkin]

The only thing I can think of is that something (tool, etc.) got up in the driveshaft/fan area and when you started the engine something had to give.

 

[bevis]

The only thing I can think of is that something (tool, etc.) got up in the driveshaft/fan area and when you started the engine something had to give.

I wish. NO tools whatsoever in the path during start. Do you know what that
spring / lever arm is in that pic ?

 

[bevis]

it appears that there is a set screw that holds the hub on the front of the pump ( praying that there is ) . I'm going out to the garage and see if thats the case. If it is I'm going to try and get the hub off and see if i can extract those 2 sheared off bolts. I know there will be a lot of cussing involved for certain. Anyone else with any thoughts as to why this happened ? I just don't want to order $100 worth of parts and have it happen again. I can't believe that Kubota wants $76 for that fibrous type flange that interfaces the crank to the pump. Thats ridiculous but i think I'm going to need one.

 

[rbargeron]

.........parts fly across the garage.

I yank the fuel kill to stop the insanity..............

The tranny pump turns freely by hand....

the rear wheels both turn freely by hand.

obviously the motor runs.....

Was the tranny Hydro locked via air in the system ?

Breaking both bolts takes some serious forces, but this may not be a huge failure.

Are we sure the engine still turns normally? Will it run without the pump connected? Try trapping the shaft with wood to keep it from flailing around? Maybe try turning the starter with the fuel cut?

A hydro "lockup" is essentially unheard of, but a jammed gear after the hydro could cause a hard stop that would rip up the flex coupling. Without the engine running the hydro becomes free turning, A trans problem downstream wouldn't show up turning the input end of the hydro.

To verify the trans is really free try this - with it in gear, turn both rear wheels at the same time in the same direction to see if everything inside rolls smoothly. My only thought is that, during the filter screen change, a metal chip moved to where it could jam something.

To remove broken bolt ends I use a dremel tool with a thin grinding wheel to cut a screw driver slot into the face of the break. Sometimes they'll turn right out. May be able to do it in place. Dick B

 

[bevis]

Breaking both bolts takes some serious forces, but this may not be a huge failure.

Are we sure the engine still turns normally? Will it run without the pump connected? Try trapping the shaft with wood to keep it from flailing around? Maybe try turning the starter with the fuel cut?

A hydro "lockup" is essentially unheard of, but a jammed gear after the hydro could cause a hard stop that would rip up the flex coupling. Without the engine running the hydro becomes free turning, A trans problem downstream wouldn't show up turning the input end of the hydro.

To verify the trans is really free try this - with it in gear, turn both rear wheels at the same time in the same direction to see if everything inside rolls smoothly. My only thought is that, during the filter screen change, a metal chip moved to where it could jam something.

To remove broken bolt ends I use a dremel tool with a thin grinding wheel to cut a screw driver slot into the face of the break. Sometimes they'll turn right out. May be able to do it in place. Dick B

i will get it back up in the air and do those tests and post the results. I appreciate your help in diagnosing it.

 

[North Idaho Wolfman]

The spring and the rod is the hood hold down.

It's actually not that uncommon for that joint to fail it's a flex joint and if even one bolt were loose or a crack in the fiber washer it can fail, pull it apart and inspect all the parts.
And use hardened bolts (most likely metric) on reassembly

Yes the hub comes off, bolt in end and set screw or locking bolt (#200).
Use a good pulley puller to get it off if it's stuck on.

 

[bevis]

Breaking both bolts takes some serious forces, but this may not be a huge failure.

Are we sure the engine still turns normally? Will it run without the pump connected? Try trapping the shaft with wood to keep it from flailing around? Maybe try turning the starter with the fuel cut?

A hydro "lockup" is essentially unheard of, but a jammed gear after the hydro could cause a hard stop that would rip up the flex coupling. Without the engine running the hydro becomes free turning, A trans problem downstream wouldn't show up turning the input end of the hydro.

To verify the trans is really free try this - with it in gear, turn both rear wheels at the same time in the same direction to see if everything inside rolls smoothly. My only thought is that, during the filter screen change, a metal chip moved to where it could jam something.

To remove broken bolt ends I use a dremel tool with a thin grinding wheel to cut a screw driver slot into the face of the break. Sometimes they'll turn right out. May be able to do it in place. Dick B

OK, i jacked it back up to where the rear tires were off the ground.
i turned the both wheels at the same time in neutral / treadle pedal fwd / treadle pedal rev. All smooth . I put a big cable tie around the crank output shaft and started the motor. runs smooth as silk.

What do you glean from that information ?
Again, i appreciate the help.

 

[bevis]

The spring and the rod is the hood hold down.

It's actually not that uncommon for that joint to fail it's a flex joint and if even one bolt were loose or a crack in the fiber washer it can fail, pull it apart and inspect all the parts.
And use hardened bolts (most likely metric) on reassembly

Yes the hub comes off, bolt in end and set screw or locking bolt (#200).
Use a good pulley puller to get it off if it's stuck on.

WOW, awesome
Thank you soooooo much. I could not figure out for the life of me what i had done wrong.
Am i correct that the bolts final resting place is unimportant because there is a groove machined around that entire banjo fitting ? Im talking about the bolt that is part of the sump screen. There is a hole machined through the middle of that bolt. I put 2 new O-rings on the banjo fitting and i marked the head of the bolt so i would know where that hole through the bolt was. When i tightened it up, that hole ( looking at my mark on the bolt head ) did not line up perfectly with the banjo fitting exit to the feed pipe. Its probably 20 degrees past it. Is that ok ?

 

[Diydave]

Post a pic of the broken bolts, showing the broken ends of the bolts...

Looks to me that one sheared straight across, and the other sheared on a diagonal.

Looks to me like the first one may have been cracked for a while, and sheared off.

Then the next one broke at an angle, as the flex plate changed angle, due to the stress of being the only bolt holding...

Not having a picture of the broken edges, I can speculate no further...

 

[bevis]

Post a pic of the broken bolts, showing the broken ends of the bolts...

Looks to me that one sheared straight across, and the other sheared on a diagonal.

Looks to me like the first one may have been cracked for a while, and sheared off.

Then the next one broke at an angle, as the flex plate changed angle, due to the stress of being the only bolt holding...

Not having a picture of the broken edges, I can speculate no further...

Well if i NEVER have to get that hub off agin, it will most certainly be wayyyyyyyyjyyyyyy too soon... No set screw as the spec drawing shows. Press fit with keyway. OMG i promise you don't want to try and get a puller in there and manipulate it. The only thing i can think of thats much worse than that is the 2 top bell housing bolts in that 68 big block nova in the background. Both of my arms and hands look like i have been in a fight with a badger. Here are the pics and it appears that you are correct because the sheared bolts do not look the same.
I assume i need to replace that flex plate even though it is not cracked or broken. But the holes are wallowed out where those bushings rest. Im not sure how that flex plate even works.

 

[bevis]

here are the pics of the hub. I'm letting some pb blaster soak in overnight

 

[bevis]

also any answer on this part of the question ? ? ?

Am i correct that the bolts final resting place is unimportant because there is a groove machined around that entire banjo fitting ? Im talking about the bolt that is part of the sump screen. There is a hole machined through the middle of that bolt. I put 2 new O-rings on the banjo fitting and i marked the head of the bolt so i would know where that hole through the bolt was. When i tightened it up, that hole ( looking at my mark on the bolt head ) did not line up perfectly with the banjo fitting exit to the feed pipe. Its probably 20 degrees past it. Is that ok ?

 

[North Idaho Wolfman]

I replied on this yesterday and somehow it disappeared????

First the spring and the rod is the hood hold down, should have had 2, one on each side.

looking at the wear marks, it was loose or was assembled wrong.
Yes the fiber (disk) joint is bad, pulled the bolts right threw it.
The fiber joint allows the drive shaft and the HST to be coupled in a way that the engine, shaft, and HST do not have to be in perfect alignment and still work properly and without binding.

For that system to work efficiently, properly and safely, it needs to be assembled properly with the right parts and tight!

 

[Russell King]

also any answer on this part of the question ? ? ?



Am i correct that the bolts final resting place is unimportant because there is a groove machined around that entire banjo fitting ? Im talking about the bolt that is part of the sump screen. There is a hole machined through the middle of that bolt. I put 2 new O-rings on the banjo fitting and i marked the head of the bolt so i would know where that hole through the bolt was. When i tightened it up, that hole ( looking at my mark on the bolt head ) did not line up perfectly with the banjo fitting exit to the feed pipe. Its probably 20 degrees past it. Is that ok ?

You are correct. The bolt position in relation to the fitting is not important.


Sent from my iPad using Tapatalk

 

[bevis]

I replied on this yesterday and somehow it disappeared????

First the spring and the rod is the hood hold down, should have had 2, one on each side.

looking at the wear marks, it was loose or was assembled wrong.
Yes the fiber (disk) joint is bad, pulled the bolts right threw it.
The fiber joint allows the drive shaft and the HST to be coupled in a way that the engine, shaft, and HST do not have to be in perfect alignment and still work properly and without binding.

For that system to work efficiently, properly and safely, it needs to be assembled properly with the right parts and tight!

Thank you so much for your help. Any suggestions as to the cheapest place to get those parts ?

 

[bevis]

You are correct. The bolt position in relation to the fitting is not important.


Sent from my iPad using Tapatalk

awesome ! as i looked at it i didn't think so but i thought i had better verify it considering what happened as soon as i fired the motor right after tightening that fitting up and refilling with hydro fluid.
I really appreciate the help

 

[North Idaho Wolfman]

I buy most of my parts from these guys:
http://www.colemanequip.com/Kubota_Parts.asp

You can go to Kubota.com and get the part #'s:
http://www.kubota.com/part/partsList.aspx

 

[bevis]

I buy most of my parts from these guys:
http://www.colemanequip.com/Kubota_Parts.asp

You can go to Kubota.com and get the part #'s:
http://www.kubota.com/part/partsList.aspx

Thanks for the links