Bobcat Flat Face Couplings

[LWG]

I recently bought a grapple bucket for my T200. The machine is old, but new to me. I was able to attach the couplers the first time with just a little trouble. After that, it seemed impossible, especially if I just had disconnected the bucket, and then went to reattach it. I tried the pressure relief switch in the cab, but nothing seemed to work. I couldn't figure out where in the Bobcat the problem was.

I did some research and found some posts on this site. It seems a lot of the problems result from residual pressure in the attachment, and not in the machine. There's an easy way to test for it. Since the flat face couplers are the same between the machine and the attachment, I just try to connect male-female on the attachment. If they go in, the pressure in the attachment has dissipated. If not, there's still residual pressure in the attachment.

I'm sure this is not new to the old hands out there, but for us newbies, it might be a help.

 

[JD8875]

My grapple bucket is notorious for this if it sets and the grapples settle. You will quickly learn to remember to hook the hoses together when you unhook from the machine, after your first bath in hydraulic oil because you had to open the couplers.

John

 

[dirty4fun]

Welcome to the great world of flat face couplers. I bleed the pressure off and then disconnect them, and then attach them back so they can't build pressure. That works most of the time, the rest of the time two wrenches and loosen the fitting, or fittings. When it is cold they will freeze, and you can't hook them up without warming them. The ones on the snow plow will freeze, and sometimes have pressure even though they have been connected, to each other. The plus is on a cold day it does warm you up, in more than one way.

 

[LWG]

My particular problem was that my machine is old and unfamiliar. I assumed that since the attachment was new, and the machine old, that the problem was with the machine. As it turned out, I think the machine was running properly, and the "problem" was with the attachment. I think I will just loosen one of the fittings a fraction, just so it weeps a little.

 

[PDG X]

As a suggestion on any grapple bucket for anybody's machine. When you set the bucket down to disconnect it, open the grapple about half way and set both edges on the ground - with bucket facing downward. After releiving presssure in the machine and tool, disconnect the hydraulics and immediately connect the tool lines together. That way as the tool heats up in the sun, if there is any pressure buildup on one side of the cylinder or the other, the clam will move against the ground as the pressure will move from one side of the cylinder to the other, instead of building up pressure against a closed clam that cannot move. After picking the tool back up and coupling to the machine, make sure you relieve the pressure in the machine before trying to recouple the tool lines to the machine.

 

[ctheddy]

Or just apply pressure to the clamps and watch your hose as they will tense up then back the clamps off till the hose go limp, disconnect and your good to go. Hooking the hoses together may equalize residual pressure but not relieve it... but it will keep your ends clean and your oil clean and so on...