Clutch finger confusion

Mon Nov 26, 2012 12:53 pm

I split Eddie this past weekend to attend to the rear main. As long as I had her split, I figured I would check the finger height on the clutch (Rockford). They were all equal, at 1 3/4 inches from the base of the pressure plate. I double checked what they were supposed to be, and several posts stating the height should be 1 1/4 inches, so that's what I set it at. However, when I get her back together, that did not give enough travel to release the pressure plate from the clutch disk. So I adjusted them out about another 1/8 inch. When I started her up, I got a chattering sound almost immediately, when I pushed on the pedal. I adjusted the fingers out another 1/8 inch. Now I can push the clutch in enough to shift, but if I push it too far, it still chatters.

Before I started, I could push the clutch pedal all the way to the stop without any noise. I was not having any trouble with the clutch before I started (should have left well enough alone), but figured that I should get things at their proper setting (just because it's working, doesn't mean it's working correctly). Is there something wrong with my pressure plate? Is there any downside to having the clutch fingers adjusted out where I had them to start with?

One further note. Before I started the adjustment, I noted that the heads of the adjusting screws were just above the locknuts, which is how they appear in the photos I saw in the various posts while checking to see what the correct height was. When I got done setting them at 1 1/1 inch, the head of the adjusting screw was well above the locknut.

Re: Clutch finger confusion

Mon Nov 26, 2012 2:17 pm

1. What is your pedal free travel set at?
2. Do you have about an 1/8" gap between the front of the clutch release bearing and the outermost point of the pressure plate fingers?
3. What is the condition of your clutch release bearing? (how much wearable surface above the retainer)
4. Is the steel rod that supports the clutch release bearing retainer worn and have grooves in it?

Here is a pic of a new bearing from TM Tractor, note the thickness above the retainer:

http://www.tmtractor.com/new/cl/378fp.htm

Here is a good visual from Rudi's manual server about some of the things I asked above:

http://www.cleancomputes.com/Cub/Cub%20 ... e%2057.jpg

Re: Clutch finger confusion

Mon Nov 26, 2012 2:23 pm

And I am assuming you are taking your 1 1/4" measurement from the correct location on the pressure plate:

Image

Re: Clutch finger confusion

Mon Nov 26, 2012 3:20 pm

If the stock screws are in place, typically at 1 3/8 to 1 1/2, the heads will be flush with or just below the jam nut.

Re: Clutch finger confusion

Mon Nov 26, 2012 4:46 pm

cubguy47 is right. You also have to adjust the pedal travel. The adjustments don't leave a lot of allowance, and the pedal adjustment is no different.

Todd

Re: Clutch finger confusion

Tue Nov 27, 2012 8:08 am

The clutch assembly has to be installed on the flywheel to adjust the fingers. From your narrative, I gather that it was not.

Re: Clutch finger confusion

Tue Nov 27, 2012 8:48 am

Thank you for the replies. No, Gary, the clutch was not bolted to the flywheel when I measured. That's probably where I went wrong. I'll make the adjustment measuring tool and re-check this week-end.

In answer to Cubguy's question, I set the free play to 1", which gave me about 1/8" clearance between the release bearing and the fingers. the bearing surface is worn down half or less, and those are the points I used to measure. I did not check the rod that holds the release bearing for grooves.

But, if I do end up having to adjust the fingers to more than 1 1/4" to get rid of the clatter, what is the downside to that (provided the free play and bearing to finger clearance is correct)? As I said, the clutch operated fine before I monkeyed with it.

Re: Clutch finger confusion

Tue Nov 27, 2012 9:27 am

Quick tip put loctite on the jam nut after your adjustment.

Re: Clutch finger confusion

Mon Dec 03, 2012 8:42 am

Well, I adjusted the clutch fingers to 1 1/4", and everything is fine. Discovered that a paint stirrer is the perfect thickness to check the throwout bearing to finger clearance, so there's another use for your gas guages.