Backhoe bh75 dipper rod bent

bigballer · Mar 26, 2012

the dipper rod on my bh75 was damaged (bent) and i am wondering if i need to have some special tools to replace it? has anyone done this or is it best to take it to a shop to have them swap the rod out? could the bent rod cause damage to any of the internal parts on the piston, cylinder, or seals?

you get bonus points if you can guess correctly how it was damaged. the hoe was not digging when this happend, in fact the tractor was not even running.

wdchyd · Mar 26, 2012

Lemme guess.....Someone back into it??

If the rod gets sucked in, it could do more damage to the gland, piston head or barrel

look and see if the gland is cracked from the outside...... with the rod extended all the way out off the machine, see if the rod is sloppy in the gland, you shouldn't see any slop

Best to take apart to determine if it just a routine rod/seal change or more...

Deano · Mar 27, 2012

Don't hook the backhoe to something, ie. root, and try to drive the tractor to pull it. A friend of mine did that and bent his piston on the dipperstick.

Deano

Baby Grand · Mar 27, 2012

Sorry to hear about the dipper rod. Did you ding a tree limb while trailering?

radioman · Mar 27, 2012

technically, you don't need special tools. it depends on the shape on inside. If you are not sure, I'd remove it from your BH with standard wrenches and take whole thing to hydrualic shop and ask for opinion. As long you didn't try to retract it, I would just leave as it till its looked at. some cylinders need spanner groove wrench or pin type wrenches or its welded shut.

Chances are a shop will prefer to replace rod, they could try to put it in a press and straighten, but they will tell you it can leak and no gaurantees.

Why not post a picture of it before taking it off? make sure you post pics of ends too.

bigballer · Apr 5, 2012

here are some pics it does not look as bad as i think it is..

wdchyd · Apr 5, 2012

This would be a good case for straightening.......if you decide to do it, a shop press with thick alum sheet metal chunks will protect the chrome from damage and a dial indicator helps to see when you get it close to straight

A seal kit and you're off on your way.....

CHDinCT · Apr 6, 2012

So do we have a winner yet on how it got bent? Curious to know so I don't make the same mistake. And I hope you can have a hydraulic or machine shop straighten it out for you. Looks to me that it can be bent back into position.

Herkypilot · Apr 6, 2012

Deano said:
Don't hook the backhoe to something, ie. root, and try to drive the tractor to pull it. A friend of mine did that and bent his piston on the dipperstick.

Deano

Yup! Brother in law did this very thing also. Same result and very obviously bent. He had a B75 or B77 BH, not sure which. About a $2k mistake as I recall. He let the dealership fix it. Ouch!:ashamed:

bigballer · Apr 6, 2012

it's about $450 for the rod and seal kit + 30 minutes of shop time. if i decide to buy a complete new cylinder it's around $600. i think i'll try to have the local shop put in in a press and see if they can straighten it. it is not leaking currently and the outer ring looks OK.

wdchyd was correct on how it got bent, someone (not me) backed into it and let me tell you if anyone actually tried to do this would not be successful. i know how it happened but still don't beleive it. the receiver hitch on the truck entered right between the dipper arm and the rod and the ball wedged between the two. they tried to pull the truck out but it would move the entire tractor. anyway a call was placed and i rushed home to assess. i had to start up the tractor and fanagle the hoe around for it to let loose as it was in such a perfect angle it did not want to let go of the ball.

wdchyd · Apr 6, 2012

Bigballer,

That rod shouldn't be anymore than $150 to 200 to make if you have an independent hyd shop make it.....easy to repack yourself

It may be 30mm (or close) chrome stock....I'd bet it will straighten fine..

Here's a video of me making one for a TBN member here.... 3 Minute Hydraulic Rod - Tractor Videos - Kubota, John Deere, New Holland and More

bigballer · Apr 6, 2012

wdchyd said:
Bigballer,

That rod shouldn't be anymore than $150 to 200 to make if you have an independent hyd shop make it.....easy to repack yourself

It may be 30mm (or close) chrome stock....I'd bet it will straighten fine..

Here's a video of me making one for a TBN member here.... 3 Minute Hydraulic Rod - Tractor Videos - Kubota, John Deere, New Holland and More

i'll call around and see what i can find. the prices i quoted were from the dealer so yes, i'm sure they mark it up quite a bit..

nice video btw, what would you charge for one of these?

Ductape · Apr 7, 2012

Bill, that vid won't go past the 1:42 mark for me. Maybe it's on my end?

Impressive machine.

crazyal · Apr 7, 2012

Unless you don't want to learn how to do it I would rebuild it yourself. Sooner or later you'll have other seals fail and once you do the first one the rest are much easier. There's a local guy around here who straightens them and can cut the eye off and weld a new rod on it to repair them. Finding his name was difficult and I ended up finding a used cylinder for the same price.

wdchyd · Apr 7, 2012

bigballer said:
i'll call around and see what i can find. the prices i quoted were from the dealer so yes, i'm sure they mark it up quite a bit..

nice video btw, what would you charge for one of these?

Yours will be metric stock so that ups the price (for material) a little but that basic rod would be approx $150.

The chrome plated stock is expensive but I buy it in 24' lengths and cut the eye off like Crazyal said.....

I stock inch sizes .500 up to 4.000 and metric sizes from 20mm to 100mm

Any machinist can do this job but many cannot do it any quicker or as nice a machine job as the CNC lathe....

wdchyd · Apr 7, 2012

Ductape said:
Bill, that vid won't go past the 1:42 mark for me. Maybe it's on my end?

Impressive machine.

The vid works on my end......What's really nice with the machine is the touch-screen and the repeatability......if I wanted to make 20 parts they'd be all the same

I can program, verify (the simulation to make sure I didn't screw-up the program) and run......then go make a cup of tea and done.....

Deano · Apr 7, 2012

Awesome video! Amazing how the threads are cut. I wanted to see that part thinking the machine would slow WAY down and cut the thraeds all at once in one pass. Neat how it makes continuous passes at high speed.:thumbsup:

wdchyd · Apr 7, 2012

Deano, other people here that run CNC's can attest to it but that machine is capable of running even faster.....I chose to keep it under 1000 rpm's but it will go to 2000 rpm's when cranking.....the computer speeds it up while cutting as the dia gets smaller to keep the SFM (surface feet per minute) the same when cutting.......it will take off the threads all in one pass but I prefer multiple passes for better carbide life..

Compared to doing it manual it's incredibly fast

kcender · Apr 9, 2012

After reading this post,I started thinking I should fix the bucket cylinder on my BH90 backhoe.It is bent also and has been for some time,probably close to a year and a half.It worked fine and didn't leak so I never bothered with it.The bend is opposite to the OP's but about the same deflection judging by the photos.I called the dealer to get some prices but he said it would be much cheaper to go to a hydraulic shop.Kubota wanted 700 dollars for the rod and 130 dollars for the packing kit.I took the cylinder off myself and disassembled it.This is the first time I have ever done this but it wasn't too difficult.I took the rod,gland,and cap to two different hydraulic shops for their opinion.Both said the gland was fine but needed new seals and O-rings.These were 10 dollars.The rest of the seals were as good as new and didn't need replacing.They said to make a new rod would be around 300 dollars but I got them to sell me a piece of 40 mm stock for 60 dollars.I can get the machining done at work on a CNC machine.I will weld the eye on myself as I am a welder by trade.With a jug of UDT fluid to top up what was lost,the total cost should be around 100 dollars which is pretty cheap.I chalk the whole thing up to a learning experience.As to how the rod got bent I am not positive but I think it happened when I was pulling a tree with a chain hooked to the BH bucket.The tree fetched up on a stump and I think this is how it happened.At the time I didn't realize this was a no-no but now I see it is,another lesson learned.