Grader wheel hop

[layinpipe93]

Run a 772 GP Deere. Falls one way, falls wing, 16' moldboard. Only in my second year of strictly snow removal on gravel roads, so no experience blading gravel. Normal blading speed is 19, seventh gear wide open. Having trouble with machine bucking like a bronco under heavy load. I've tried articulating slightly so the rear wheels are pointed towards center of the road, tried it with front wheels leaned left, tried it with and without front wheel assist, tried 60 pounds of air in front tires, 55 pounds in rear tires, CANT GET IT TO STOP. Drives me nuts because it's a rough ride and the people using the road have to feel that chop. Looking for any and all suggestions!

 

[Jonas302]

Assuming your using the moldboard behind the front plow, plain steel or carbide cutting edges, carbide can set up washboards in the snowpack under the right conditions seen it mostly with front plow changing your blade discharge angle and tilt can make a big difference

Is the grader tight in the blade slides and circle lift cylinders ect, Floating or holding if the machine is getting loose it can work better to hold down so its not bouncing in the sloppiness

Hope you get it figured out

 

[Welder Dave]

This was talked about in the past and I think the general consensus was sometimes you have to just slow down.

 

[layinpipe93]

Assuming your using the moldboard behind the front plow, plain steel or carbide cutting edges, carbide can set up washboards in the snowpack under the right conditions seen it mostly with front plow changing your blade discharge angle and tilt can make a big difference

Is the grader tight in the blade slides and circle lift cylinders ect, Floating or holding if the machine is getting loose it can work better to hold down so its not bouncing in the sloppiness

Hope you get it figured out

Yes it's a very tight machine, 1700 hours and greased regularly. Using the moldboard all the time as well. Never run in float, I honestly don't even know how to put the MB in float!

 

[layinpipe93]

This was talked about in the past and I think the general consensus was sometimes you have to just slow down.

I have noticed that slowing down helps, however the wing won't throw the snow far enough if I slow to 15. Occasionally I run 25 mph but she still bucks under heavy load

 

[Mobiltech]

I don’t run a grader but have been told it has a lot to do with tire pressure. Some will put each tire at a different pressure so they don’t bounce at the same rate. I’m not sure what the secret is but I think some are much lower than the pressure you are using.
I’m sure someone here knows more on this.

 

[Blue-Fox]

They tend to crow hop when you are running too fast. Road grader is not meant nor built to withstand the beating from high speed ops. Gears above 6th are "traveling gears" and 6 wheel assist is not functioning above 6th gear anyway. (disengages) Whoever is expecting you to operate at that speed should be run off. You will end up hammering that machine to death and eventually - driving over your moldboard, literally.

 

[Welder Dave]

I have noticed that slowing down helps, however the wing won't throw the snow far enough if I slow to 15. Occasionally I run 25 mph but she still bucks under heavy load

How much snow are you pushing? Maybe need to plow more often or push the snow back further after each plowing so it will throw further the next time.

 

[westerner]

The Caterpillar Operators Manual for the 140H in this situation specifically says 'slow down'.....

 

[layinpipe93]

They tend to crow hop when you are running too fast. Road grader is not meant nor built to withstand the beating from high speed ops. Gears above 6th are "traveling gears" and 6 wheel assist is not functioning above 6th gear anyway. (disengages) Whoever is expecting you to operate at that speed should be run off. You will end up hammering that machine to death and eventually - driving over your moldboard, literally.

Township board prefers if I go faster to save tax dollars, and I never really wanted the job so speed doesn't bother me. This machine actually keeps front wheel assist on thru seventh gear, but not eighth. Honestly I hit eighth any time I can pull it and it isn't hopping.

 

[layinpipe93]

How much snow are you pushing? Maybe need to plow more often or push the snow back further after each plowing so it will throw further the next time.

Currently I'm able to get it shoulder to shoulder doing one pass on each side of the road. However we're in the wide open prairie, so one storm can leave 1 to 5 ft tall drifts. I just go out as soon as the wind quits blowing.

 

[layinpipe93]

I don’t run a grader but have been told it has a lot to do with tire pressure. Some will put each tire at a different pressure so they don’t bounce at the same rate. I’m not sure what the secret is but I think some are much lower than the pressure you are using.
I’m sure someone here knows more on this.

I think I will try the different pressure method. Can't hurt much at this point

 

[layinpipe93]

The Caterpillar Operators Manual for the 140H in this situation specifically says 'slow down'.....

Do you know if they are referring to slowing down when blading gravel, or snow? Everybody around here preaches high speed on our flat land, but I do agree with you that slowing down would help. I'm just afraid it isn't feasible in my situation.

 

[Welder Dave]

Township board prefers if I go faster to save tax dollars, and I never really wanted the job so speed doesn't bother me. This machine actually keeps front wheel assist on thru seventh gear, but not eighth. Honestly I hit eighth any time I can pull it and it isn't hopping.

You won't be saving any money and their roads won't be getting plowed at all because the grader will be getting expensive repairs. I wouldn't think you'd have much pushing power in 7th and higher gears especially if you're using a wing. Abusing the machine never results in cost savings.

 

[cuttin edge]

The government wants you to run fast here on main roads. It's the same thing, they don't want snowbanks. I have run full speed, but it is on asphalt, and they keep you out plowing for the entire storm. I have done long stretches of road, came back the other lane, and had enough snow down to hit it again. Never had that issue, and mine is not 6 wheel drive. Some guys use float, but I prefer to be in control of the machine. You might need to go out out more often, or slow down, and if they don't like it, let them try it.

 

[Oxbow]

It's an age old problem inherent to blades. If your roads are frozen float may help as the blade won't follow the hop as closely. I suspect it has a lot to do with out-of-round tires. There are threads on HEF that talk about the problem, and I think some will stagger pressure in the rear tires - front left and rear right 5psi higher or lower than rear left/front right for example.

The only sure-fire cure is less speed.

 

[Blue-Fox]

Township board prefers if I go faster to save tax dollars, and I never really wanted the job so speed doesn't bother me. This machine actually keeps front wheel assist on thru seventh gear, but not eighth. Honestly I hit eighth any time I can pull it and it isn't hopping.

Township Board doesn't know the first thing about safe operation of a motor grader. When that unit gets away from you (from any one of a random hydraulic issue) and you destroy the machine or run over a car I guess maybe they will listen? Anyway, its a combo of cutting edge bite in the surface and tire pressure is the key to stopping it or at least minimized by spreading your tandems tire pressure about 5 pounds or more. When you are finish blading its generally normal to throw 10-15 lbs extra to stop the crow hops.

 

[Pickawinna]

First up I know nothing about plowing snow. Don't even get the stuff where I am in outback Australia.
But operating a grader at those speeds for anything other than travel is mind blowing to me. 19 KmH would be bad enough but I guess you are talking MPH which is even more insane.
Have you tried bringing your tyre pressure down? More traction and less bounce.
Roll the moldboard forwards so its not cutting under and pulling machine down then causing the machine to bounce up when the material breaks away and releases the pressure?
Radial tyres on it?

 

[Moraisclaudio]

Run a 772 GP Deere. Falls one way, falls wing, 16' moldboard. Only in my second year of strictly snow removal on gravel roads, so no experience blading gravel. Normal blading speed is 19, seventh gear wide open. Having trouble with machine bucking like a bronco under heavy load. I've tried articulating slightly so the rear wheels are pointed towards center of the road, tried it with front wheels leaned left, tried it with and without front wheel assist, tried 60 pounds of air in front tires, 55 pounds in rear tires, CANT GET IT TO STOP. Drives me nuts because it's a rough ride and the people using the road have to feel that chop. Looking for any and all suggestions

Run a 772 GP Deere. Falls one way, falls wing, 16' moldboard. Only in my second year of strictly snow removal on gravel roads, so no experience blading gravel. Normal blading speed is 19, seventh gear wide open. Having trouble with machine bucking like a bronco under heavy load. I've tried articulating slightly so the rear wheels are pointed towards center of the road, tried it with front wheels leaned left, tried it with and without front wheel assist, tried 60 pounds of air in front tires, 55 pounds in rear tires, CANT GET IT TO STOP. Drives me nuts because it's a rough ride and the people using the road have to feel that chop. Looking for any and all suggestions!

Hey try do this, work in 5th gear, put your MB at maximum angle 45º using the circule table tilting your blade just a little bit, lean your front tires towards whatever direction the snow is flowing.

 

[Cat 140M AWD]

I plow at the same speeds you do and what I can tell you is set your one way up to be about an inch off the road surface and take everything with your one way I hate using moldboard unless I have to I find if I use just front plow and wing the hoping goes away I just got a new falls XPR reversible plow last February best thing we’ve brought I average 20 plus mph now.