tilt cylinder

[reno611]

I have a 643 model Bobcat, 1988 model year. Tilt cylinder was replaced last month as cylinder and piston end was deeply scored and seals destroyed..Now it is again failing to hold in position. Probably has more loose metal in fluid causing seal damage. I want to repair it myself, that is if cylinder is not scored as last time..I have quit using it hopefully to prevent deep scoring should metal flakes again be the problem.. I watch the mechanic take the cylinder loose, but did not witness his taking it apart..where do I start? Bobcat want an arm and leg for a new cylinder, this rebuilt one was just an arm.. Metal in fluid? Does not the filter clean up some of this? Change filter again etc??? Any suggerstions would be appreciated..

 

[jsimpson]

Hydraulic pump may be going south. Metal to metal contact produces metal shavings. The filter is on the pickup side of the pump, so it won't keep the worn pump from generating shavings.

 

[reno611]

Hydraulic pump may be going south. Metal to metal contact produces metal shavings. The filter is on the pickup side of the pump, so it won't keep the worn pump from generating shavings.

Thanks for the input. Hydrolic pump shavings are probably the cause of the metal..another HUGE expense. I still would like to take the cylinder apart..last time the mechanic planted the forks into the ground, took the lines off, took the pin out of the top..and I miss his taking the cylinder apart exposing the rod and seal etc. ..any suggestions?

 

[StuZ]

Thanks for the input. Hydrolic pump shavings are probably the cause of the metal..another HUGE expense. I still would like to take the cylinder apart..last time the mechanic planted the forks into the ground, took the lines off, took the pin out of the top..and I miss his taking the cylinder apart exposing the rod and seal etc. ..any suggestions?

Better find out where the shavings are coming from first. Are they metal, or aluminum ?? You can flush the hyd. system 3 and 4 times after the repair, and still need to change the filter after a few hours of operation. As far as the cylinder goes, after you get it off, put the barrel end in a vice, and if you don't have the proper spanner wrech, you should be able to unscrew the end cap of the cyl with a dull punch, IF it was just apart. Pull the rod end out, and remove the nut holding the piston on. Replace the seals on the piston, and the oring inside the piston. I know the cyl. is expensive, but don't waste a seal kit if there are deep grooves in the barrel. A good hyd. shop can hone and coat the barrelm and MAYBE save you a 100.00 Good Luck

 

[reno611]

Better find out where the shavings are coming from first. Are they metal, or aluminum ?? You can flush the hyd. system 3 and 4 times after the repair, and still need to change the filter after a few hours of operation. As far as the cylinder goes, after you get it off, put the barrel end in a vice, and if you don't have the proper spanner wrech, you should be able to unscrew the end cap of the cyl with a dull punch, IF it was just apart. Pull the rod end out, and remove the nut holding the piston on. Replace the seals on the piston, and the oring inside the piston. I know the cyl. is expensive, but don't waste a seal kit if there are deep grooves in the barrel. A good hyd. shop can hone and coat the barrelm and MAYBE save you a 100.00 Good Luck

Thanks for the information. One more question..what is the technique for flushing the system? Again thanks..now to fine a good shade tree. WBL

 

[StuZ]

Thanks for the information. One more question..what is the technique for flushing the system? Again thanks..now to fine a good shade tree. WBL

Cheapest way I have found is a mixture of hyd. oil and diesel fuel. Just enough hyd oil to keep things lubed while you run and operate the cylinders briefly. It will take a few times to do it right, and maybe twice with fresh oil afterwards to get the diesel fuel all out. If you use a magnet AND get some filings out with it, slap a speaker magnet on the bottom of the hyd. tank. About the only metal in the system is the gears in the pump, or a spool.

 

[reno611]

Cheapest way I have found is a mixture of hyd. oil and diesel fuel. Just enough hyd oil to keep things lubed while you run and operate the cylinders briefly. It will take a few times to do it right, and maybe twice with fresh oil afterwards to get the diesel fuel all out. If you use a magnet AND get some filings out with it, slap a speaker magnet on the bottom of the hyd. tank. About the only metal in the system is the gears in the pump, or a spool.

I really appreciate all of your input. Now to the job at hand. Thanks again.

 

[StuZ]

I really appreciate all of your input. Now to the job at hand. Thanks again.

Let me know how you make out K ??

 

[reno611]

Let me know how you make out K ??

StuZ Man you ain't gonna believe this..am I snake bit or what? Planted the 48" fork in the ground to better see the connections, right? Left it that way overnight. Next morning I go out and the machine has lifted the front wheel off the ground and its sitting back on its butt...well, I climbed over into the cab careful to stay from under the arms etc..go to start it up and the battery is DEAD...cannot open the door...I just decided to leave it until I return week after next...Any more suggestions other that placing a "For Sale" sign on it?...Snake Bit in the cold North Florida woods...

 

[reno611]

Let me know how you make out K ??

StuZ Man you ain't gonna believe this..am I snake bit or what? Planted the 48" fork in the ground to better see the connections, right? Left it that way overnight. Next morning I go out and the machine has lifted the front wheel off the ground and its sitting back on its butt...well, I climbed over into the cab careful to stay from under the arms etc..go to start it up and the battery is DEAD...cannot open the door...I just decided to leave it until I return week after next...Any more suggestions in the mean time other that placing a "For Sale" sign on it?.....All I need now is for my brothers Larry and Moe to show up. To be continued...

 

[wademaniac]

Did you ever get your 643 fixed?e-mail me at [email protected].