I just got my new cat 305.5 ecr and the thumb can't hold anything. When I pick something up the thumb looses pressure and what I pick up falls out. I am in the south pacific so far from a cat rep. Does anybody have any ideas?
Auxiliary relief valves are probably low. Should be able to roll your bucket into the thumb and have some pressure but the bucket should over come the thumb as not to do damage to the thumb cylinder. Some of the cat guys will be able to get you a picture from sis. If you post your serial number it will make it easier.
FKY02879 is the model number I can move the thumb by hand, it has no resistance....
Sounds like it is set up fro one way (hammer) flow instead of two way (thumb) flow. There should be a valve at the base of your boom to redirect the oil through the control valve. Take a look in the operators manual behind the seat for auxiliary hydraulics and it should explain the process there.
Thanks ben46a thats all it was.....I can see its nothing like a medium size machine I will be learning things for quite some time.
Good to hear you got it figured out. First time I ran into that issue was on a 315 I had put a thumb and lines kit on. The kit was for one or two way flow and had a similar valve at the base of the boom. Got a call from an irate boss tellling me to get out to the machine and fix whatever I had screwed up because the thumb was floating. I drove out to the site, laughed and moved the operators track cleaning shovel that had hit the valve and turned it to hammer circuit. I never forgot that one. I'm pretty sure the customer got billed for my travel time to move his shovel as well!
I have another question, I ordered the 305.5 with a 60 cm bucket and was deliverd a 50 cm bucket because with the hydraulic Quick attachement and the thumb, it can only be a 50 cm. I found out that the next size up for my machine is a 91 cm bucket. My question is, can the 305.5 handle that size of bucket in digging applications? Thanks for your answers.
I'm going to go out on a limb and guess, without seeing a part number, I'd guess that the 91cm bucket is just for ditch cleaning or clean up. I wouldn't recommend it for general digging. A 50 cm bucket would be about the largest I would use on a 5 tonne machine.