CAT 143H Tire inflation

[Deeretime]

Hi i know there is alot of knowledge on here and i need some advise i have a blade that won't stop walking when im finnishing and i have continetal radials on the machine.
Im not sure if it is an inflation problem rite now or just the tires that i have on it
if someone could let me know the best Psi to run a blade at it would be greatly apreciated

 

[biggrader]

oooooh...... the old tire pressure thing. There is a thread on this problem. it is.
https://www.heavyequipmentforums.com/Forum/showthread.php?t=16001. Haven't figured out how to reference it like the pros on this forum but it is on page 3 of the motorgrader section about half way down. As far as me I run the pressures in my continentals probably a little higher than most. I'm @ 65-70 lbs/ on the rears and 50 in the fronts. the pressures on the rears vary depending on what attachments I have on the back. (ie. ripper,packer,snow wing,disc.)

 

[Deeretime]

oooooh...... the old tire pressure thing. There is a thread on this problem. it is.
https://www.heavyequipmentforums.com/Forum/showthread.php?t=16001. Haven't figured out how to reference it like the pros on this forum but it is on page 3 of the motorgrader section about half way down. As far as me I run the pressures in my continentals probably a little higher than most. I'm @ 65-70 lbs/ on the rears and 50 in the fronts. the pressures on the rears vary depending on what attachments I have on the back. (ie. ripper,packer,snow wing,disc.)

Yea the tire guy recomended 50 and i know to stager the preasure, And we also have ripper, V plow and wing on ours so maybe 65-70 is what ill try next
:drinkup

 

[ledsel]

tire pressure.

Check this out it may help you. http://www.tirexusa.com/firestone/loping.html

 

[mg140h]

I have played with the tire pressure all over the board....has anyone gotten it to really work? I am wondering if it isn't just how a grader is made, the distance from the front wheels to the rear wheels. I know how to try and control it by turning the circle, slowing down, rolling mold board over to try and get as much pressure pushing up to get the slop out etc, i just have not found the way to keep it from bouncing all together.

 

[plowking740]

I noticed that you run a 143h. I ran on last year as well, and it might be you awd. I found that if it was set to high (forward), it would bounce and hop like mad. usuall kept it right back till I absolutly needed it, and then pushed it up. It was really bad a Cat Fixed it, some kind of drive/pump under the motor quit. likely is the tires, but something to think about.

 

[Grader4me]

Yea the tire guy recomended 50 and i know to stager the preasure, And we also have ripper, V plow and wing on ours so maybe 65-70 is what ill try next
:drinkup

I found that running a higher tire pressure like that cut down on my traction. I usually kept it around 50 to 55 lbs psi. I've had tires that bounced and tires that didn't. I really think it just depends on the quality of the tire.

 

[ovrszd]

I've had tires that bounced and tires that didn't. I really think it just depends on the quality of the tire.

I agree with this completely. Worst bouncing tires I've ran were Firestone Bias Ply. Hated those tires.....

 

[Deeretime]

I noticed that you run a 143h. I ran on last year as well, and it might be you awd. I found that if it was set to high (forward), it would bounce and hop like mad. usuall kept it right back till I absolutly needed it, and then pushed it up. It was really bad a Cat Fixed it, some kind of drive/pump under the motor quit. likely is the tires, but something to think about.

yea the awd cat graders are terrible they don't have it nearly as smooth as a deere but Unless im doing heavy cutting or side slopes i keep the awd off all the time.
I was looking yesterday at the tires again and the front drives look like recaps with small cracks in the side wall, The others are all new so i think its the tires because it bounces bad!
Im not a blade oporator but i have spent lots of time in them and with a good hard smooth base i cant spread in anything other than 1st if i go to 2nd at an idle or better it starts to hop.
Is that the only gear to spread in because i can do it in 3rd on our 772 verry well.

 

[Grader4me]

.
I was looking yesterday at the tires again and the front drives look like recaps with small cracks in the side wall, The others are all new so i think its the tires because it bounces bad!
Im not a blade oporator but i have spent lots of time in them and with a good hard smooth base i cant spread in anything other than 1st if i go to 2nd at an idle or better it starts to hop.
Is that the only gear to spread in because i can do it in 3rd on our 772 verry well.

Sounds to me like its the front tires that are causing you grief...I remember a few years ago I was shaping up a road that had been milled. The milled asphalt would stick to the front tires which in turn would cause the grader to bounce. I would have to drop down to first gear. At that point I would road the grader for a couple of miles to knock off the asphalt. What a pain in the butt that was..
I spread in 2nd & 3rd gear. Usually 3rd most of the time though. Lower gear when shaping.

 

[ledsel]

Aah, O.K. ? It doesn't bounce with the end wings in position?

 

[biggrader]

The other thing I have noticed with finish blading is that depending on the material being graded..... very hard base or a loose base..... with both types of base you can have problems if you do not use the diff lock. U may be spinning one side of the tandems and not even know it. Putting alot of HP to the ground and with radial tires can create a slight lope when the tires break loose. Slight lope turns into a teeth-jaring bounce that will spill the coffee all over the floor. Diff lock makes it tough for turning though or for curves.:my2c

 

[gilledp]

Gents,
MG Bounce or Loping is inherient in all MG design. You have a vehicle with no suspension and arched front frame and a large weight (the moldboard) suspended from the frame. The variations in frame rigidity, position of the moldboard, size of load on the blade, tire type and inflation pressure and moldboard angle all contribute to the speed at which the MG will begin to bounce. Changing any of these factors can change the speed at which bounce will occur. For the operator,, the options are tire pressure, blade load and blade angle. I have lots more on this subject if anyone is interested. Thanks

 

[archibald]

try ballasting your tyres with water/antifreeze mix this sometimes helps . hope this helps