Grader Power Control Questions 112 3U5103

Hi, LeakyBoot.
You ass-u-me correctly. All the fixed clutch gears are the same except the for the two on the circle reverse which have the bevel gear on them to mesh with the vertical power shaft coming up from under the floor.

Having said that, there may well be some variations between the different series of which I am not aware. I do know that there were some variations between series with the sliding clutch section and with the control yokes associated with them but I don't have the serial number lists for those changes.

IF you have an unworn face among the clutches in your machine AND a GOOD machine shop near you, you should be able to get matching new faces ground on some of the old clutch parts. The two that are most likely to have unworn faces are probably the circle reverse gears 'cos they can't be reversed.

Just my 0.02.

Hi Team,
Deas is onto it, as a general finding the Scarifier Gears and sliding collar are usually the least worn.
At the Dealer we had an Exchange Program for the gears and collars with worn dog clutches.
The gears were welded up with weld metal that I was not privy to and the gears sent out to outside Trade for machining.

I did a few cheapies by hand also by welding up and die grinding for best fit--they seemed to work--likely low hydrogen rods or some such later day better product for this type of application--your local weld supplier would be the best bet for reliable info--maybe.

There may have been a Factory drawing of the dog clutch profiles that was used, too long ago to recall now.
As Deas said, make a profile pattern of an unworn gear to work to.

Cheers,
Eddie B.

Would a new center sliding part, a 4f6992 , work as a pattern for rebuilding the two gears?

My main issue is with the circle. Not only does it kick back more than it should it also will not hold position if the blade tip hangs on a rock. Do I need the horseshoe shaped parts with the 11 springs replaced? 7F7935 can be had on ebay for around 12 dollars each. LB

Hi, LeakyBoot,
Sounds to me like the circle guides may need adjusting as well but putting the whole clutch/brake assembly in there would not hurt.

And yes, the new clutch assembly can be used as a pattern for rebuilding and/or resurfacing the others. As I understand it, the pitch and those clutch faces is pretty specific for optimum function with minimal effort. They will work with worn faces but the shape that they come from the factory with is the optimum.

To adjust the circle guides - 'bush method', center the blade square across the machine, set it lightly on the ground and drive forward until the circle hits the front pair of guides and hold the machine there by whatever means you can. (The park brake will do just fine - - - -IF it works. LOL) Dismount and check the meshing between the circle drive pinion and the circle teeth. Neither one should be touching the bottom of the other but they should be close. Adjust the front guides as needed to achieve this.

When and only when you have the front guides adjusted, then adjust the rear guides to suit. On older machines with plenty of wear, it often pays to leave about 1/8" clearance between the rear guides and the circle to allow for a bit of 'out-of-round' in the circle itself.

Then lift the blade and test the circle rotation.

http://www.acmoc.org/bb/showthread.php?20409-Cat-12-Graders-Pre-G-series

Just my 0.02.

Thanks. I just ordered a new sliding clutch for the power control and will give specs to pattern any rebuilds. LB