B670 Backhoe Rebuild

D2Cat

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Bill, your description and pictures makes me wonder what North Idaho Wolfman will end up with on that tractor. Do you have any pictures of it before you separated the hoe?

I've bought tractors that had been dis-assembled and left in boxes, and been in a barn that burned. What you have there....is a PROJECT!
 

Lil Foot

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Len, I do have some pics, but no real detail. It definitely has some of the same abuse/stupidity as the hoe, and is kinda odd on top of that. For instance, it has the new style front axle, but with only 4 lugs instead of six. Some of the bolts holding the rear hanger plates for the hoe were 1/2"-13. One of them was about 4" long. Sean can explain what he found in the engine, which was a D850 instead of a D750.
 

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D2Cat

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OK, Bill, how did the headlights survive? That's got to be a miracle.

Maybe we need a contest. The most beat up/abused Kubota.
 

Lil Foot

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OK, Bill, how did the headlights survive? That's got to be a miracle.
Accidents do happen.:D
Actually, one socket was dangling and almost none of the wiring is intact.
HST cover & both engine side covers also missing, as is the screen box over the oil cooler.
 

North Idaho Wolfman

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First let me say I was the Bad person that prompted this insanity, as Lilfoot really wanted the tractor and BH, and by the pictures it did look like it was in much better shape.
Me and Bearskinner took a road trip 16Hours round trip and picked it up.
All the time I was the fool that held out hope that it wasn't as bad on the inside as the outside looked, and really tried to get it whipped into shape before he got here, but fell flat on my backside with work on it and other work.
In my defence when we got to the tractor it was covered in a layer of oil, hydraulic fluid and dirt that covered most of the mismatched, cut, broken, poorly assembled parts up, so initually it didn't look all that bad.

I felt and feel really really bad, because Lilfoot was rather disappointed and let down when he got here to pick it up, think kid at christmas opening the toy he wanted all year, only to find it broken beyond repair ?! :eek::(:(:mad::confused::eek:

Well lets start at the front of this fine Newer Model B7100HSTD.

Hood bolts...Missing but yes headlights intact, radiator looks like a fan ran into it, but surprisingly doesn't leak, radiator hoses mismatched, oversized, cut, and spliced, radiator bolts and mounts cobbled up mess, one long bolt one short bolt, cut pieces of tire for mounts, broken lower mount. Fan belt that was frayed and worn worse than I've ever see.

The front axle as Lilfoot said, rather odd, 4 lug, but a new style axle with little to no wear that I can feel. tires mismatched, one new on front and rear one old front and rear.

Front axle pin and frame, Worn 3/8" on the frame in the rear hole and 1/8" on the pin on the large side but little to no wear on the small end, castle nut is stretched and stripped.
Another gem is that they has cut and welded on the frame all over the place to attach ????, that will take some clean up.

Engine has been swapped out with newer D850, which when first arrived was seized. I tore into it to only be more and more disgusted as I went.
They installed the flywheel wrong and broke one bolt off and stripped two others, crank will need to be retapped to be useable!

In teardown I found the springs removed from the governor so this poor thing, when it ran, had to run horrible, glow plugs shot, still need to test injectors (not holding my breath on those being any good) and will need to rebuild the injector pump.

Tough tear down as it turned out #3 piston had gotten a tiny bit of moisture in it and rusted up very minorly, but enough to lock it up.
When I finally got all the pistons out, all the rings on all the pistons were stuck, tried to unstick them and ended up breaking one.

At that point I measured the cylinders to see if it was worth rebuilding and discovered there is little to no wear on the cylinders, they were still at factory new specs, it's like the motor never really has ever run? :confused:

Wiring, complete shambles, will need completely rebuilt!

Was surprised to find a new clutch, pressure plate, throwout bearing, but not surprised that there was no pilot bearing at all in the crank at all, not worn out just never installed, motor was probably from a mower that didn't use the crank to run a propeller shaft.

HST looks complete but I have not has power to run it, I've got my fingers crossed that it's good.

Onto the rear... WOW... that pretty much sums it up.
Bolts stripped, bolts replaced with oversized SAE, bolts that were the wrong length, but mechanically internally sounds good on static spinning of parts.

Top three point arms are there but one of the lift pins had been replaced with a SAE bolt, the other lift pin was missing washers and loose. the rest of the three point is missing.

Lets not forget to mention the rear hubs, One is in good shape, the other ...yikes, evidence that they had welded it onto an axle at some point, lucky enough it doesn't look like one of these axles, the hub has two broken studs, one stripped stud, and no colters (locks) so it only held on by the set pin and flops around incredibly bad.

Now for the fun:
Most would scrap it...well not me...it's just a challange!

Massive parts are on order right now:
Full Kubota OEM rebuild kit
Doner crank out of another motor.
Thanks to 007kubotaguy, new bolts for the flywheel.
All the OEM hoses, filters, filter screens, orings, and seals for shafts, hydraulics, motor, just everywhere.
Used good rear case (fix all the stripped bolts).
Complete OEM three point.
New hub
Pile of body and frame bolts and nuts and hardware off of a B7100 to replace mismatch or stripped bolts.
Radiator mounts.

That should whip it into shape and then we'll just fine tune it.
I'll still need a grill, side covers, HST cover, Seat and seat mount (Lilfoot took the one on it as it was for the BH), ROPS.

One thing I'm seriously considering changing is the steering to Hydrostatic steering, would make it super nice if it gets a loader later.

More to come...
 

shootem604

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I can't believe you are using it as a parts recipient instead of a parts donor! Good luck.
 

Lil Foot

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1979 B7100DT Gear, Nissan Hanix N150-2 Excavator
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Lilfoot was rather disappointed and let down when he got here to pick it up, think kid at christmas opening the toy he wanted all year, only to find it broken beyond repair
Yep, that about sums it up.:D
But the more I thought about it, it is just way too much work & time for our situation in life these days. (caregivers for MIL & FIL)
I am so grateful that Sean was willing to take it off my hands. I have tackled bigger projects, but only when I had the time & patience to do them.
Had the tractor still been in one piece when I got there, I would have hauled it home, threw a tarp over it, and maybe some day tackled it, assuming I hadn't robbed or sold too many parts off it in the interim.
It will return to running condition and live a better life under Sean's capable hands than it would have with me. I need another project like I need a hole in my head. And I made out in another way, Sean sent me home with so much stuff that I think hauling the tractor home might have been lighter.:D
 

Lil Foot

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1979 B7100DT Gear, Nissan Hanix N150-2 Excavator
May 19, 2011
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Peoria, AZ
Hey Sean, I know someone who should have an extra seat soon, and maybe a set of injectors if they turn out bad. Maybe some seat bumpers also.
 

North Idaho Wolfman

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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
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Sandpoint, ID
Hey Sean, I know someone who should have an extra seat soon, and maybe a set of injectors if they turn out bad. Maybe some seat bumpers also.
I might have to take you up on that! ;)
 

North Idaho Wolfman

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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
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28,286
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Sandpoint, ID
I can't believe you are using it as a parts recipient instead of a parts donor! Good luck.
That model of tractor up here is rather pricey to buy, 4K to 6K normal selling range and that's in fair shape.
I have a great reputation for rebuilds like this, and will have several buyers that will be fighting to own this little beast when I'm done, I've already had two that wanna buy it right now (with me finish building it for them), I keep telling everyone to wait and we'll see how it turns out after some work and TLC. ;)
 

Lil Foot

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1979 B7100DT Gear, Nissan Hanix N150-2 Excavator
May 19, 2011
7,259
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Peoria, AZ
A few days ago, I unloaded my B670 parts hoe from the trailer & stashed it in the back of the garage. It was everything my little B219 FEL could handle-if it had been 3 lbs heavier, I'd have been screwed.
 

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North Idaho Wolfman

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Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
28,286
4,853
113
Sandpoint, ID
A few days ago, I unloaded my B670 parts hoe from the trailer & stashed it in the back of the garage. It was everything my little B219 FEL could handle-if it had been 3 lbs heavier, I'd have been screwed.
It was all that extra welding that they did on it! :rolleyes:
 

lparknit

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B7100HST-D
Oct 7, 2017
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Greenville
Re: Backhoe rebuild

You guys have shared such great information in great detail, making the huge rebuild task seem simple. That's experience and knowledge at its best, Thanks for your time and devotion on here.
 

Lil Foot

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1979 B7100DT Gear, Nissan Hanix N150-2 Excavator
May 19, 2011
7,259
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113
Peoria, AZ
Glad you found this thread helpful. If you happen to cover something we haven't, or find something new, please post your experience.