Backhoe 375 backhoe, bent bucket cylinder rod

[jdjllee]

Stumping a small tree with a crotch in it. Guess I somehow crowded
and bent my bucket cylinder rod. Bent pretty good, too much to straighten.
Should I just get the whole cylinder or maybe just the rod can be replaced. Is it an easy repair to replace the rod? I have most tools. Any special tools needed.? Don't have time for dealer to work on it. How much will a whole cylinder set me back?

 

[kennyd]

Well, I have no good news for you...

A new cylinder from JD is:

AM127642 BUCKET CYLINDER ADD 610.00 USD


And just the rod is:
AM127921 ROD, WELDED PISTON ADD 170.00 USD

And the seal kit is:

AM127929 KIT, SEAL ADD 29.99 USD


So basically you are looking at $200 or so to replace the rod yourself.

 

[gunmaker]

Should make a nice afternoon or evening project. Suggest working in a clean area where you can lay out the parts, maintain cleanliness. Kenny's the guy to keep in touch with if you run into problems.

 

[jdjllee]

Going to the dealer soon to see about parts or a new cylinder.
The price seems very high for what that cyllinder is. The rod must be rather soft. At first I though I may have bumped the cylinder against the tree
somehow, but I don't see any evidence that happened. Trying to get a better handle on what caused it so I can avoid the same mistake. I'll assume it was my fault for now. This tree was about 5 inch diameter on the main trunk with a crotch and 3 inch trunk off that. I had cut it off 4 foot above ground a year or more ago. The main trunk was laying over at an angle about 60 degrees off horizontal and away from the hoe when I backed up to it.
I laid the bucket out over it and curled it in (maybe too tight) extending the bucket cylinder. I then pulled the pintle in. the tree came out of the ground. I was left with a bent bucket rod. I'm thinking the action of the pintle and odd angled trunk, bucket curled around it, put a big load on the bucket tending to force the bucket open, but since the relief valve is ahead of the valve, and the bucket hydraulics are locked, something had to give.
I don't think the bucket cylinder rod would bend thru action of the bucket alone. The relief valve would limit the forces. I think I've learned a lesson here, just not sure what it is yet. I'l ltry not to pintle or boom the hoe if the bucket is into a root or rock and overly curled with bucket rod extended.

 

[Wayne County Hose]

This is common. You had one cylinder extended, that's when they're the weakest. Then you used the power of another cylinder against it. Something had to give and it wasn't the stump. The relief valve only comes into play if you have the spool valve open for that circuit. Otherwise, no relief valve.

 

[Cidertom]

been there, done that.

dealer had rod in next day and cylinderback to me that night.

I too think it is a bit much for the cylinder. I don't know about the 375 but the 448 is by ameriquip I wish it was easy to buy parts directly. When I bent mine, there was a flury of "me to's". I figure anything is going to break sometime with diesel powered equipment.

Good luck.

 

[jrutherford]

This is common. You had one cylinder extended, that's when they're the weakest. Then you used the power of another cylinder against it. Something had to give and it wasn't the stump. The relief valve only comes into play if you have the spool valve open for that circuit. Otherwise, no relief valve.

that sounds like bad engineering to me.... shouldn't the one cylinder be able to withstand the force of the other cylinder? this is upsetting as I just bought a 375. As far as I'm concerned if this happens to me it will be a warranty issue, not my fault.

 

[jrutherford]

This is common. You had one cylinder extended, that's when they're the weakest. Then you used the power of another cylinder against it. Something had to give and it wasn't the stump. The relief valve only comes into play if you have the spool valve open for that circuit. Otherwise, no relief valve.

and also, wouldn't the relief valve of any activated cylinder be engineered not to destroy another cylinder not activated? That doesn't make sense. Here is the scenario I could see this happening by: A guy is pulling major stump, doesn't have enough gusto with hoe to get it so wraps chain around bucket and stump and tugs with tractor. Now that might do it!

Not sure what is going on here, but doesn't make sense to me with these bent cylinders..... I hope this isn't common, because I will not be happy if this happens to mine.... it is a design flaw.

 

[mfreund]

With enough force anything will break and the one thing no mfg will cover: loose nut behind the wheel!!!

 

[SFish]

I agree with JRutherford, and in addition I just don't see where the sideways pressure, perpendicular to the ram, would come from to start the piston rod to bend. Because both ends pivot the pressure should be straight in line with the cylinder and excess pressure should just blow the packing. The only things I can think that would start a rod to bend are a frozen pivot point, a pivot point manufactured off center, or a rod that was previously bent a little (e.g. from backing into something).

Steve