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Hydraulic compatability for attachments.

Theweldor ยท 2018-12-06 18:45

Here is the issue. Several Cat hoes ranging in size from 335's to 315's all have the same wedge coupler system. The trouble is hooking up hydraulic lines for all the attachments that fit these machines. The hoes have all different sizes of blocks and fittings on them. Without a bushel basket full of adapters to follow each machine or attachment at times you don't have the fittings to run an attachment that is well within the machines limits. We have been toying with the idea of buying all matching blocks to mount on the booms so everything matches. This would include pressure and return hoses, case drains etc. Some times you have up to 5 lines on an attachment. I guess the question is what do you all do or have done to make this fool proof. Or isn't that possible?

Replies6
  1. #1heymccall2018-12-06 19:26

    Unsure what wedge coupler is? Mine are all pin grabber couplers. My PC120, PC128, ED150, 312, 314 all have #17 size Stucchi hose quick connect couplings. Everything else in B,C, BC, CD, D, DB linkage are running #21 size Stucchi quick connect couplings. Or, in simpler terms, 1" adapters on first size, 1-1/4" adapters on everything bigger.

  2. #2John C.2018-12-06 19:28

    I've run into this before with Cat wedge couplers. Basically you shouldn't be running attachments made for a 315 on a 335. The gallonage for each is different so the size of the hoses and fittings will be different. The thickness of the lugs is different between the smaller machines and the larger ones. I had one customer tearing up 320 buckets and wondering why. I visited the job site several times and caught the operators using the smaller machine buckets on the 330s and we washed all their warranty claims down the drain. If you have machine attachments that are close in hydraulic capacity, say a plate compactor that fits a 335 and want to use it on a 320, and the hydraulic flows are nearly the same you shouldn't have a problem. If you want to try running a 335 size compactor on a 315 your results will likely be sub par.

  3. #3Theweldor2018-12-06 19:40

    We are not trying to run attachments for a 315 on a 335. That part is understood. It seems that between a couple of years the hydraulic fittings have been changed on what should be compatable machines. Sending a handful of hydraulic adapters is absolutely idiotic in my opinion. They always seem to get lost in transit somehow. I have never really understood why some of this stuff is not more standardized as far as fitting goes. The type of coupler isn't the issue, it is the vast array of hydraulic fittings that screws everything up.

  4. #4John C.2018-12-06 19:42

    I'm guessing you are talking about things like pipe fittings, JIC fittings, ORFC and then flange fittings?

  5. #5Theweldor2018-12-06 19:51

    Yes, That is more the issue.

  6. #6willie592018-12-06 22:08

    If you're talking about connections to the aux pipes on the stick, it's not that the fittings have changed over the years, those fittings have all been out there for years, it's just the OEM decides to use different fittings. On my rental fleet I fitted all my excavators with JIC fittings at the shutoff valve on the stick, -16 for 200 class and below excavators and -20 for 300 class and above. Choose what fitting you wish to work with, JIC, ORFS, 4 bolt flange, and change all your machines to accept the choice you've made, no need for various adapters then.