I'm looking at an 8T No. 12 road grader; Just can't get my wife to drive the tractor while I work the No.33 pull grader any longer!
I have heard these machines referred to as "knuckle busters", and I suspect it has something to do with the mechanical control levers.  What causes these lever(s) to be "knuckle busters"?  Is this a serious short coming and should there something I should look for when buying one?

nothing that can't be fixed when they get worn out the drive dogs will bounce in and out of drive if your hand is on the leaver. In the worst case, you can punch the window or break it. the second thing is people try to operate them like a hydraulic valve and just open it a little. you can't feather the controls the drive it's in or out always the same speed if everything is rust and not well taken care of it can be harder for the drive box to do its job so more force is needed. if taken care of and used with the right mind set there are no problems like most equipment understands what's going on and give it respect and you'll make out just fine. it's also just a way to tell the difference between mechanical and hydraulic graders.

Like Martin said, they are only knuckle busters until you get used to it. Firm movements, no pussy footing around when moving the levers.

Hi Delta KJ.
There izza 'ar-tickle' on the maintenance and adjustment of these jiggers which I put together some years ago. - covers most of what you would need to know.

www.acmoc.org/bb/search?query=Adjustment...te=all&childforums=1

Hope it helps.

Just my 0.02.

a family friend used to drive a old 12e when he was a kid his dad was a grader op for the shire council. later on his dad was hired to put in the strip at port macquarrie nsw they gave him a new hydraulic machine to use he persevered for a day or so then asked for the 12 back he said he couldn't feel the road with the hydraulic machine. he used to place his hands on the levers and feel the vibration coming back so he knew if he was taking to big a bite or not. years later the surveyed the strip he was only out by around a inch and he had don it by eye and feel. goes to show you dont need some of this fancy electronic shit just take your time and have some pride in your work.

Hi, Folks.
The biggest mistake that I see when watching blade operators doing final grade work is that they try to go too quick. A good, old fashioned 'Mark One Eyeball' final grade controller can only make corrections at a certain rate.

BUTTTT, in my limited experience with them, even the later 3D GPS/UPS systems can't make corrections much faster. It IZZA slow game and machine stability at speeds come into it too.

Just my 0.02.

Thanks for the responses and special thanks to Deas Plant for taking the time to document the functionality of the mechanical controls.
If I can negotiate the price, I'll buy the 8T grader.

Hi, Delta KJ.
I would suggest looking at all of those areas when inspecting the machine. Also, stand about 8 - 10 yards behind the machine on the centerline and check the tandem cases to see if they are both standing up straight. If either one is leaning OUT toward the bottom, the 'square bearing' on the inside of the tandem case is shot - bulk bucks.

If you have the chance, put it into HEAVY load, enough to spin the rear wheels and check that all 4 wheels are spinning. If one is not spinning one one side, you have a broken drive chain in the tandem case. If BOTH are spinning on one side, you have either TWO broken chains or a broken drive shaft 'coz these old girls do NOT have a differential. It is locked up crown wheel and pinion to ensure full drive to all four rear wheels all the time.

You can check the drive chains individually by removing the four cover plates on top of the tandem chain cases. There is also an oil level check plug on the outside of each chain case near the center pivot bearing.

If you can post a few photos, some of us may come up with some more things to check.

BTW, yer welkum too ther 'doco'. I cain't see any sense in gathering that kind of knowledge and then taking it to the grave with me.

Just my 0.02.

Hi, Folks.
On another note, it is possible to lift ANY wheel off the ground, tandems INCLUDED, using the blade lift. To get tandems on one side off the ground, with the blade square across the machine, raise the front end about 18" off the ground. Then RAISE the blade on the side away from the one you want to lift the tandems off the ground.

Even the hydraulic machines will do this, many even with a rear ripper attached.

Just my 0.02.

who needs a jack when you have machine power.

when dad worked for avokah irrigation one of the boys got bogged and had to get the farmer where they were working to snig the truck out, another of the staff nicknamed grandad pryor told this bloke your in a crane truck you shouldn't have been stuck enough to need towing out, you use the crane to pull and push yourself out of the bog.