Register free!
Search
 
     

The Green Industry's Resource Center


Click for Weather
Reply
 
Thread Tools Display Modes
  #21  
Old 06-27-2009, 11:30 AM
Tigerotor77W Tigerotor77W is offline
LawnSite Bronze Member
 
Join Date: Mar 2004
Location: Charleston, SC
Posts: 1,873
Ooops. I meant closed-center. Am I making any sense at all? I guess I meant to ask whether most SSLs are open-center systems, not open-loop/
Reply With Quote
  #22  
Old 06-27-2009, 08:57 PM
Total Earthworks's Avatar
Total Earthworks Total Earthworks is offline
LawnSite Member
 
Join Date: Sep 2007
Location: Brisbane, Australia
Posts: 20
My understanding is that the Komatsu utilizes a unique Closed loop load sensing system with integrated power control within the hydraulic system. Certainly having test driven various other skid steers such as ASV's, cats etc significant difference is noted in the way the machine manages anti-stall. Other machines give the clear indication that anti-stall is managed through the fuel pump resulting in significant variation in engine rev's and power when bogging into a pile. The komatsu maintains constant engine rev's and instead varies the hydraulic flow to match speed to load, accordingly, as the load increases when bogging into a pile, the hydraulic system reduces the speed of the machine, slowing rotation of the wheels and increasing torque and traction. To some this may appear as being under powered as it will not spin the wheels, however what it does mean is consistent full buckets, minimal tyre wear, less ground disturbance and less shock loading on the machine

From a usability perspective, I prefer the Komatsu

Just my two cents worth
__________________

www.totalearthworks.com.au
Brisbane,
Queensland,
Australia.
Reply With Quote
  #23  
Old 06-27-2009, 11:55 PM
SiteSolutions's Avatar
SiteSolutions SiteSolutions is offline
LawnSite Bronze Member
 
Join Date: Apr 2007
Location: Huntsville, AL
Posts: 1,098
Quote:
Originally Posted by Total Earthworks View Post
My understanding is that the Komatsu utilizes a unique Closed loop load sensing system with integrated power control within the hydraulic system. Certainly having test driven various other skid steers such as ASV's, cats etc significant difference is noted in the way the machine manages anti-stall. Other machines give the clear indication that anti-stall is managed through the fuel pump resulting in significant variation in engine rev's and power when bogging into a pile. The komatsu maintains constant engine rev's and instead varies the hydraulic flow to match speed to load, accordingly, as the load increases when bogging into a pile, the hydraulic system reduces the speed of the machine, slowing rotation of the wheels and increasing torque and traction. To some this may appear as being under powered as it will not spin the wheels, however what it does mean is consistent full buckets, minimal tyre wear, less ground disturbance and less shock loading on the machine

From a usability perspective, I prefer the Komatsu

Just my two cents worth
I don't really think that's accurate. The old rowing-oars skid I had managed anti-stall via my ears and arse directing my arms to push less. The SJC machine I have now manages anti-stall by destroking the pumps, a.k.a. "varies the hydraulic flow". I would imagine Cat does the same thing. I don't have any gadgetry on my fuel pump to vary fuel flow according to load. That's how a Briggs & Stratton lawnmower manages anti-stall. It's called a governor. My loader aint got one of them, and I bet BC Ron's kitty doesn't have one either... but he would be able to tell you better than me.
Reply With Quote
  #24  
Old 06-28-2009, 11:49 AM
bobcat_ron's Avatar
bobcat_ron bobcat_ron is offline
LawnSite Fanatic
 
Join Date: Nov 2007
Location: Abbotsford, British Columbia
Posts: 9,943
Quote:
Originally Posted by SiteSolutions View Post
I don't really think that's accurate. The old rowing-oars skid I had managed anti-stall via my ears and arse directing my arms to push less. The SJC machine I have now manages anti-stall by destroking the pumps, a.k.a. "varies the hydraulic flow". I would imagine Cat does the same thing. I don't have any gadgetry on my fuel pump to vary fuel flow according to load. That's how a Briggs & Stratton lawnmower manages anti-stall. It's called a governor. My loader aint got one of them, and I bet BC Ron's kitty doesn't have one either... but he would be able to tell you better than me.
The engine has a governor, that's the adjustment on the injection pump I made earlier this year, even in the exploded pats manual it shows the governor control bolt and the torque sensor below it.

And that's another thing, the anti stall isn't just a valve like everyone thinks, there's an actual sensor below the drive gears from the injection pump coming off the crankshaft, if that sensor drops to a slower RPM, then the relief between the 2 piston pumps kicks in and it destrokes the pumps.
But when you do the "turning up" on the injection pump, you are basically adjusting the governor to keep the sensor from dropping down faster, and when you do the anti-stall adjustment, you are increasing the relief and destroke pressure.
__________________
The amount of energy necessary to refute bullsh*t is an order of magnitude bigger than to produce it


http://www.youtube.com/user/69rd96
Reply With Quote
  #25  
Old 06-28-2009, 02:36 PM
ksss's Avatar
ksss ksss is offline
LawnSite Fanatic
 
Join Date: Jan 2003
Location: Rigby, Idaho
Posts: 6,963
Quote:
Originally Posted by Total Earthworks View Post
My understanding is that the Komatsu utilizes a unique Closed loop load sensing system with integrated power control within the hydraulic system. Certainly having test driven various other skid steers such as ASV's, cats etc significant difference is noted in the way the machine manages anti-stall. Other machines give the clear indication that anti-stall is managed through the fuel pump resulting in significant variation in engine rev's and power when bogging into a pile. The komatsu maintains constant engine rev's and instead varies the hydraulic flow to match speed to load, accordingly, as the load increases when bogging into a pile, the hydraulic system reduces the speed of the machine, slowing rotation of the wheels and increasing torque and traction. To some this may appear as being under powered as it will not spin the wheels, however what it does mean is consistent full buckets, minimal tyre wear, less ground disturbance and less shock loading on the machine

From a usability perspective, I prefer the Komatsu

Just my two cents worth
One of the issues with these machines is with the pattern selector. To be able to have a pilot controlled skid steer with a pattern changer your having to assume that all flows to all functions including drive wheels are equal, there not ideally. This is why no else has put a pattern changer in a pilot controlled machine, not TK, not CASE/NH or CAT. If you want to switch patterns you have to change the plumbing via a kit. I cant speak of durability but they give up considerable performance to have the pattern changer. I liked several things about the machine. I liked the feel of the pilots, nearly ideal balance between feel, and resistance in the controls. The lap bar I thought was an interesting idea, putting all the guages on there. Komatsu has not made the progress they were anticipating with this machine, at least not yet. That cab forward thing that Komatsu uses and now BC, makes visibility to the back much more difficult at least with the Komatsu.
__________________
See us at www.kaiserskidsteer.com

Proudly running CASE and Takeuchi equipment.
Reply With Quote
  #26  
Old 06-29-2009, 04:32 AM
Total Earthworks's Avatar
Total Earthworks Total Earthworks is offline
LawnSite Member
 
Join Date: Sep 2007
Location: Brisbane, Australia
Posts: 20
Not all komatsu's have pattern changes, Mine certainly does not. In fact mine has the benefit of having pilot controls with foot pedals, I find this setup excellent for working with a Harley rake as with the foot pedals I have far greater control over fine movements than I have experienced with pilot control machines where everything is on the joystick. It allows me slowly lower the rotor of the rake in nice and progressively.

I don't mind the rear vision on mine, with the optional mirrors fitted on the arms I find that I personally have far better vision than I do in say the Cat 299's, Toyota Huskies or Case machines.

THEse are all personal and subjective opinions of course, for me the machine works really well and would not hesitate replacing it with a new one.
__________________

www.totalearthworks.com.au
Brisbane,
Queensland,
Australia.
Reply With Quote
  #27  
Old 09-07-2009, 01:09 PM
bobcat_ron's Avatar
bobcat_ron bobcat_ron is offline
LawnSite Fanatic
 
Join Date: Nov 2007
Location: Abbotsford, British Columbia
Posts: 9,943
I thought I would bump this back up for someone who has contacted me for information on this topic through another forum.

The injection pump, the long brown cap is the one to look for, use a vise grip to grab it and whack with a hammer, there is C-clip holding the cap on the jamb nut, it is on the left side, on the bottom of the pump:



This is what it will look like, not my picture) loosen the jamb nut (the one against the pump housing) and turn out the bolt at least 1/2 a turn, and tighten the jamb nut, or rev the engine until you see a bit more smoke out of the muffler, not copious amounts, just a wisp:


The relief valve on the valve bank, on the right side of the frame:

***Loosen the center nut and turn the outer nut out and tighten center jamb nut, test before and after to verify***

__________________
The amount of energy necessary to refute bullsh*t is an order of magnitude bigger than to produce it


http://www.youtube.com/user/69rd96
Reply With Quote
  #28  
Old 09-08-2009, 09:10 PM
CarterKraft's Avatar
CarterKraft CarterKraft is offline
LawnSite Senior Member
 
Join Date: Sep 2006
Location: DFW, Texas
Posts: 290
Quote:
Originally Posted by bobcat_ron View Post
The engine has a governor, that's the adjustment on the injection pump I made earlier this year, even in the exploded pats manual it shows the governor control bolt and the torque sensor below it.

And that's another thing, the anti stall isn't just a valve like everyone thinks, there's an actual sensor below the drive gears from the injection pump coming off the crankshaft, if that sensor drops to a slower RPM, then the relief between the 2 piston pumps kicks in and it destrokes the pumps.
But when you do the "turning up" on the injection pump, you are basically adjusting the governor to keep the sensor from dropping down faster, and when you do the anti-stall adjustment, you are increasing the relief and destroke pressure.
OK Ron you I am fixing to pull your CAT credentials.

On a B-series and back machine there is no interface from pumps to engine. The engine drives a load and the pumps pump oil. The speed sensing pressure is proportional to engine RPM so.... As engine RPM drops speed sensing pressure lowers accordingly, thus swashplate angle is minimized and consequently so is flow. Pressure and power remain the same but flow drops causing a reduction in speed. The pump governor is trying to maintain the engine RPM at the predetermined torque check level yielding max engine torque. Again no connection between the engine fuel settings and pump controller. No sensors solenoids etc.

Now when you raise the speed sensing pressure you are fooling the pump into basically raising the point the anti-stall kicks in, or eliminating alltogether bcuase the destroke doesn't happen as aggressivly.

You can S-can it all together if you want by moving some lines but why?
if the tires spin how much power do they put to the ground? Do they wear tires faster? Do more work?
I am all for hot rods but watch any operator on any jobsite the rookies are the only ones spinning tires.
Reply With Quote
  #29  
Old 09-09-2009, 01:55 PM
bobcat_ron's Avatar
bobcat_ron bobcat_ron is offline
LawnSite Fanatic
 
Join Date: Nov 2007
Location: Abbotsford, British Columbia
Posts: 9,943
This was only intended for the guys with track loaders, and OTT units.
__________________
The amount of energy necessary to refute bullsh*t is an order of magnitude bigger than to produce it


http://www.youtube.com/user/69rd96
Reply With Quote
  #30  
Old 09-09-2009, 06:01 PM
CarterKraft's Avatar
CarterKraft CarterKraft is offline
LawnSite Senior Member
 
Join Date: Sep 2006
Location: DFW, Texas
Posts: 290
huh?

no difference from track to tire either, except of course C-series.
Reply With Quote
Reply

Tags
247b2 , anti , cat , skidsteer , stall

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump





Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ©1998 - 2012, LawnSite.comô - Moose River Media
All times are GMT -4. The time now is 03:06 PM.

Page generated in 0.11830 seconds with 7 queries