Anyone have any experience or advise using an auxillary hydraulic power supply for running an accessary, looking to get around (constant) 35 gpm - 3000 psi at the end of the stick. I have seen large machines outfitted with auxillary units mounted on the counterweight. Anything available for smaller (8-12t) machines? Lifted an old diesel generator for a guy last week and got to thinking u could replace the generator with a pump, streamline the cowl a little and its all there, even wired with a remote operating pannel. (of corse a little engineering to match pump, engine, add resivor, cooler, mounting system etc..)
I have seen a cat 312 on this site somewere with a auxillary engine for running a mulcher on the stick! Is that the type of thing your thinking about?
Yes, a mulching attachment.
It's not that hard to do depending on the size and manufacture of machine. A 30 ton machine can run 35 GPM pretty easy off the auxiliary spool and still run the rest of the functions at a little slower than normal rate. A 20 ton or smaller machine requires diverter valves and some fancy hydraulic work to make that gallonage and still run the machine. An 8-12 ton machine doesn't make 35 GPM in the first place so running a big mower or mulcher is not real practical unless you add another power unit. I had a customer a number of years ago that modified the counterweight on a PC120-5 and added a power unit with a piston pump just for the mulcher. It worked OK.
I seen a power unit on the back of a 312.... nothing fancy ... just a unit instead of counterweight... It was set-up as a low overhead augercast drill
Found this outfit that makes stand alone power pack, not sure how well it would hold up to the beating it would take riding on the back of an excavator. Hoping to find somthing a little more suited i.e. element proofed. $ 21k is a chunk of change for an experiment. rather find somthing that has been field tested. Love to see a photo of a working unit installed. http://www.fosterhydraulics.com/page/diesel/67_hp.html Thanks
I Know that these are bigger than 8 to 13 ton like you said but they will give you ideas! Found them on there website www.shinncutter.com
To size such a pack correctly, you’ll want to match: Pump displacement to deliver ~35 GPM, Engine HP to handle ~35 GPM × 3000 psi = 61 HP theoretical (plan for 70–75 HP after losses), Reservoir volume typically 2–3× pump flow, Oil cooling capacity need only if for continuous duty. Smaller excavators rarely have factory kits for this size of flow, so a bolt-on HPU is often the most reliable and economical route. Some users add a piggyback pump to the machine’s existing pump stack, but on 8-12t machines, i wouldn't recommend it as often overloads the engine during peak digging loads. You can refer to this {link removed} if you like to know about it and calculate it. Hyperlink removed by moderator
I’m quite sure that there have been major developments made in the auxiliary hydraulic back pack units and availability in the last 13 years. You sir, Bot or not have won the thread resurrection of the friggin decade. Congratulations and happy new year! LOL.
Happy new year