RonL
Active Member
I haven't been on the site in a while. Currently looking to buy either s skid steer or a utility tractor. Anybody have comments and experiences with these machines?
RonL
RonL
-
Thank you for visiting HeavyEquipmentForums.com! Our objective is to provide industry professionals a place to gather to exchange questions, answers and ideas. We welcome you to register using the "Register" icon at the top of the page. We'd appreciate any help you can offer in spreading the word of our new site. The more members that join, the bigger resource for all to enjoy. Thank you!
Cat 246D & 272D XHP
- Thread starter RonL
- Start date
RonL
Active Member
What I'm trying to wrap my head around is the Tier 4i and Tier 4f standards and also how the high output hydraulics work. I was told that you can plug an electric connector in and the machine adjusts output accordingly. Again, I haven't been around in a while and need to bring myself up to speed.
RonL
RonL
RonL
Active Member
OK. I've been studying this DPF and DEF matter enough that it is giving me a headache. Let me pose this question. If you have at least one attachment that would utilize high output hydraulics is there any disadvantage to having high output hydraulics? Can you run regular output attachments on the high output machine? This is what's confusing me.
RonL
RonL
The hi-flow is only activated by the electrical harness from the tool when it is plugged into the machine. There is a jumper between pins F an G that complete the circuit. If it is a 'dumb' hi-flow tool like an auger, there is a dummy plug that is used to do the same thing. If a non- hi-flow tool is used, there is no jumper in the WT connector so it doesn't activate the circuit.
So there is no 'disadvantage' to having hi-flow machine.
So there is no 'disadvantage' to having hi-flow machine.
RonL
Active Member
The standard flow 246D puts out 23 GPM at 3335 PSI. The high flow 246D puts out 32 GPM at 4061 PSI. The 272D XHP puts out something like 40 GPM at 4061 PSI. As I understand it these machines have variable output pumps. I'm assuming that unless the high flow circuit is activated the machine bypasses at 3335 PSI and puts out in the area of 23 GPM. Is this a correct assumption?
Are the high output machines more problematic? In the long run is the maintenance on the machine more expensive?
Sorry for all the questions but I'm trying to wrap my head around all the variables before I spend the money.
PDG. I have a Ford F350 Powerstroke, A Cat 416C IT, A Cat D3G, and a crapload of other tools. Looking to add to the collection.
RonL
Are the high output machines more problematic? In the long run is the maintenance on the machine more expensive?
Sorry for all the questions but I'm trying to wrap my head around all the variables before I spend the money.
PDG. I have a Ford F350 Powerstroke, A Cat 416C IT, A Cat D3G, and a crapload of other tools. Looking to add to the collection.
RonL
My understanding is that the machine uses a the same pump and the wiring harness essentially tells the machine if you have a high flow attachment hooked up. it then allows the valve spool to open up allowing more than the standard flow to go out to the attachment. I think the load sensing system Cat uses has a pressure compensator allowing either 3335psi or 4061psi to control the destroking of the pump swashplate when the max operating pressure is reached. So in essence, the high flow pump is the same as the standard flow on high flow machines and I would think that it doesn't make it more problematic.
The earlier hi-flow machines just had a second gear pump that was engaged for hi-flow. The XPS and XHD machines use a piston pump which makes controlling flow a lot easier.
Not sure how they control the pressure change from low (3335) to hi-flow (4061). A piston pump will normally put out full pressure all the time. **** Maybe one of the dealer guys can help here. ****
I'm on my second XPS machine and have not had any maintenance issues with either hi or low flow hydraulics other than wearing out an ocassional quick connector. I would much rather have a piston pump instead of a gear pump though as the likely hood of a wear is much less as long as you keep the system clean.
Looks like the evolution of machines followed a plan. We must be doing the same types of work. The D3G is a good machine. Recently ran a K for a week - lots of improvements, but getting heavy for a small machine.
Not sure how they control the pressure change from low (3335) to hi-flow (4061). A piston pump will normally put out full pressure all the time. **** Maybe one of the dealer guys can help here. ****
I'm on my second XPS machine and have not had any maintenance issues with either hi or low flow hydraulics other than wearing out an ocassional quick connector. I would much rather have a piston pump instead of a gear pump though as the likely hood of a wear is much less as long as you keep the system clean.
Looks like the evolution of machines followed a plan. We must be doing the same types of work. The D3G is a good machine. Recently ran a K for a week - lots of improvements, but getting heavy for a small machine.
Last edited:
RonL
Active Member
Glad I got those machines before all this "Tier" crap evolved. The Mitsubishi 5 liter 6 cylinder engine is a gem.
I was originally looking for a utility tractor in the 80+ PTO HP range. They also are beset with this "Tier" BS. Need something to do the finish work after the backhoe and bulldozer are finish their work. Also wanted something that I could do maintenance and upkeep ( plowing, snowblowing, bushhogging, etc.) with.
If they keep up with this pollution control stuff we will have an absolutely pristine environment. And EVERYTHING that we buy will be made in China.
RonL
I was originally looking for a utility tractor in the 80+ PTO HP range. They also are beset with this "Tier" BS. Need something to do the finish work after the backhoe and bulldozer are finish their work. Also wanted something that I could do maintenance and upkeep ( plowing, snowblowing, bushhogging, etc.) with.
If they keep up with this pollution control stuff we will have an absolutely pristine environment. And EVERYTHING that we buy will be made in China.
RonL