CCU unit #29 brake and clutch adjustments

Hi, Brian.
Garlic Pete has raised a good point here about different terms and being clear on what is meant. Some people refer to setting the neutral position - aligning the hole and the actuating roller - as 'timing' the CCU when in fact no 'timing' is involved. What is being done is setting the neutral position so that the clutch can be adjusted accurately. This is a MUST so that the clutch free travel can be set properly, which is what you are doing when you adjust the clutch.

Glen's 'trick' of using Ajax powder to clean up the brake band and drum and get a little more out of the brake is a good one and works best if you can use a puffer pack to spray the Ajax into the gap between the two ends of the brake band while someone is working the lever to release the brake.

Just my 0.02.

Hey Deas,

Doesn't setting free play have to do with timing of the way it works??? Setting the free travel correct changes the way it responds... This is the timing I'm referring too. I'm not asking you to agree with me, but I don't agree with your statement that the adjustment has nothing to do with timing of the operation of the unit.

Hey Deas,

Doesn't setting free play have to do with timing of the way it works??? Setting the free travel correct changes the way it responds... This is the timing I'm referring too. I'm not asking you to agree with me, but I don't agree with your statement that the adjustment has nothing to do with timing of the operation of the unit.

Hi, Glen.
I suspect that the use of the term, 'timing', came from having to align the two marks to set the neutral before adjusting the clutch but I don't see how anything is actually being 'timed'. What you doing when you set this adjustment is establishing a reference point for the beginning of the free travel of the lever from 'neutral' to the point where it engages the clutch. Once that 'reference point' is established, you can then adjust the clutch for the correct amount of free travel on the lever before the clutch engages.

This 'reference point' should also allow enough movement of the control lever to mover the brake actuating roller right up to the 'float' position - assuming there are no obstructions blocking the control lever movement.

I had never heard the term, 'timing', used in regard to the setting of the neutral position until I came over here for the first time - - - never had heard it back home and I doubt you will find it in the instruction book. I am on another PC at the moment or I would post the instruction scans that Old Magnet so generously posts every once in a while for enquiries like this.

Just my 0.02.

Deas Plant,

I was looking over what you posted on your first reply to me and have a question or two. First, when I tried turning the clutch adjusting nut with a wrench (and then a pipe wrench) counter-clockwise like the manual says, the control lever wanted to move AWAY from the seat not toward the seat. You had indicated that a helper would be able to feel pressure pushing it TOWARD the seat.

Second, when I tried moving turning the clutch adjusting nut count-clockwise, it would not budge. I had someone trying to turn it while I held the control lever, but it just wanted to push right through my resistance. Am I missing something, or do you think the nut is frozen or clutches locked up somehow? Or, possibly, maybe the manual said counter-clockwise but meant clockwise?

Thanks in advance.

Hi, Brian.
Sorry. My boo-boo. As you try to turn the clutch adjusting nut against the resistance of the control lever, it WILL want to push the lever away from the seat. As for the nut rotation, an easy guide is to have someone move the control lever while you watch which way the control arm moves inside the CCU. Whichever way the control arm moves, the clutch adjusting nut usually needs to turn towards it, in other words move to meet it. On the right hand side, if my memory serves me right, this would equate to turning the nut counter-clockwise.

What you have in there is basically a 'nut' and a 'bolt' threaded into each other. When you move the control lever, you are forcing these two threaded components to work to push the multiple clutch plates together to drive the drum. When you release the control lever, it allows the threads to unscrew a little thus releasing the clutch plates from their contact and stopping the drive to the drum - pretty much the reverse of a crawler steering clutch which is engaged and driving until you release it.

Hope this helps.

Hey Deas,

I do understand around the world deferent people use different words to describe things. This is a mechanical unit. It's not too hard to figure out. The "Reference Point" you describe moves as time and wear occurs. As the brake band wears, that point moves it's reference point(timing mark), and after time effects the units ability to stay adjusted correctly. Once the point isn't at proper set point, and the further away from that point, the more difficult it is on its ability to perform correctly. The timing of the operation is out of sequence and needs to be reset to compensate for the brake band wear.

I remember my Father over 50 years ago settling an argument between two of my older brothers. Jim saw a Porsche drive past us as my Father drove us on a trip in a Chyrler station wagon. "Did you see that Porcha", my brother Jim screamed out. Pat replied,"Hey, it's not a Porsha, it's a Porsche" !!! Well that started it and for 20 minutes all we heard was, "it's a Porche", "Nope it's a Porscha"!!! Jim was getting heated, and the loudest, so Pop turned and slapped Jimmy upside the Head and said, "Jimmy, I don't care what we call you now, but it'll be either an Ass or an Aus, but which ever one It Is, that's What You Are, so sit down and Shut Up"!!! Hahahaha

So call it a reference point, or call it a timing mark. It's the hole in the lever... Hahahaha
Glen