Cylinder on my Dump Truck blew up

[wushaw]

Fine job Eddie and like has been said it is time to build you a support rod for whenever you need to work on it.

 

[gemini5362]

Eddie that looks exactly like the scissor lift on the used dump trailer I bought.
Is it a "heil"

 

[Ryan03]

If I had to guess, I would say that the reason the bolts broke was due to fatigue from shaking your loads back, or backing up and hitting the brakes to get your load to slide out. I see this type of failure a few times a year in the salt trucks that I repair for a living. we have a fleet of 40 or so 5 ton Internationals and tandoms, our trucks are used for ditching and asphalt all summer, and plowing and salting all winter, sometimes when a driver gets a load of wet muck from ditching, or a hardened load of salt, he is forced to backup quickly and hit the brakes to get the load to slide out. this puts an enormouse strain on the piston rod and cylinder case, I have seen 3in rams sheared in half, cylinders torn out of bed subframes, and the top of cylinders torn off like yours. Many companies such as vibra and big bertha make bolt on 12 volt "shakers" for dump beds that decrease the need to backup and hit the brakes, but sometimes, even with a shaker, you still have to do it. I have been guilty of it too. I think it was just a coincidence it broke while lowering the bed. Over the past 10 years, I have changed about 20 bed cylinders, and it never gets any less scary climbing in the pinch point of a raised dump bed, no matter how many wood blocks, towmotor forks, and safety props you have under it. Glad to see you got it going and everything went well.

 

[CATMAN]

Eddie, I hope you plan on replace both hydraulic lines. Hyd. Lift lines and Hyd. lowering lines. There has to be a reason that when the hydraulics were used to force the raised bed downward, that this action raised the hydraulic pressure so much as to blow the cap off and break all those threaded rods. I am surprised a pressure relief valve in the system didn't protect this from happening. I just think something else may be the "root cause" of this failure. I hate to see you repair the cylinder and have it happen a second time. Could there be debris/restriction in the "raise" circuit or control valve that didn't "dump" the fluid quickly enough back to the reservior on the down stroke of the dumpbed? Note: Old hyd. hoses can get the internal rubber to flake off or create a rubber flapper inside that act like a one-way check valve, they also balloon up inside and restrict flow. This is why I would like to see new hyd. hoses installed. Also consider flushing the system a little(waste a little hyd. fluid) before you reattach your rebuilt cylinder. Good Luck.

 

[rdln]

I'll bet you didnt know you had so many guardian angels till you posted this thread

 

[toolaholic]

Eddie great fix ! Didn't You repair this hoist in 2006?

 

[CurlyDave]

I bought Grade 9 bolts and cut the head off of them. Then I cleaned up the remaining part of the old bolts and welded the new ones to the side of the old ones. I figured this would keep everything lined up right.

Eddie:

I am not certain about this, but I think grade 9 bolts get a lot of their strength from the heat treatment they have been through. Welding might not be good for them.

Next time, weld lugs on the cylinder, with through holes for the bolts...

That is a very fast fix, good luck with it.

I am constantly amazed at the jobs you will tackle alone.

 

[mopacman]

The one system that I have seen with two hoses used the back side of the cylinder as an extended resivour. This also keeps the back side of the cylinder clean insted of sucking in wet, dirty air. Larry

 

[3RRL]

Eddie,
I think you did a really good job fixing that thing as fast as you did. I'm glad nothing happened having to work with the bed tilted up like that, that must have been a scary experience. Looks like you had it blocked up pretty good though. I would take the suggestion of adding HD steel props, as your dump truck should have had those as a safety feature.
Great documentation of your repair.
Thanks for sharing.

 

[scott_vt]

Afternoon Eddie,
Thats gettin er done !!! Yeah I would be nervous about gettin pinned inbetween those rails and the dump body ! I would have so much cribbing in there I wouldnt be able to get any work done

Nothin like savin a buck !