D2 5U17027 Main Clutch

Good evening all!

New member…New old Cat for me.

I’m working on a 1956 Caterpillar D2, serial 5U17027, and I’m trying to diagnose a problem with the main clutch control before I make any adjustments.

The main clutch lever does not consistently snap over center or stay engaged properly. I found that the clutch control shaft coming out of the housing has noticeable vertical movement.

If I physically push the shaft downward while engaging the clutch, the lever snaps over center normally and stays engaged. If I allow the shaft to move upward, I lose the proper over-center action.

There also appears to be essentially no spring tension/preload on the shaft assembly.

According to my 5U13237-up parts catalog, the clutch control assembly contains:

5F5873 – Spring
S-94 – Washer
6B4967 – Seal
3H9108 – Yoke
1B8714 – Key

Before I tear into it, I’m trying to determine:

1. Is the 5F5873 spring supposed to provide downward preload/location for this shaft?

2. Is any noticeable vertical movement of this shaft normal, and if so, approximately how much?

3. Has anyone seen a broken, collapsed or missing 5F5873 cause this exact problem?

4. Does anyone know a source, superseded number, dimensions or specifications for 5F5873?

5. Does anyone know the dimensions or a current replacement/source for the S-94 washer?

6. Are there any other common wear points in this assembly I should inspect while I have it apart?

I have not adjusted the main clutch or steering clutches yet. I want to correct the mechanical movement in the control assembly first so I’m not compensating for a worn or failed part with an adjustment.

I can post photos of the shaft movement.

Any help greatly appreciated!

Welcome to the site. Maybe I can help awaken the real mechanics. I have never seen a hand clutch that was meant to have up and down motion, so there is major wear some place. But as tuff as this old Cat stuff is, it might function anyway with proper adjustment.

As for the parts, when Cat put all numbers on the computer these old numbers need 0's added to them to have the right amount of digits. My brain is tired like your tractor. I think the 0 goes in front and you need 6 total. But I could be wrong. If we had emoji's handy I would give you a "wink" and say try it. Not like pulling the clutch out and putting it back and hoping it works, without seeing a real problem.

Hi and welcome,

the S94 becomes 0S0094 to make the Cat computer happy. From my Best Thirty tractor manual parts listing it gives :- 1 11/16" OD X 1 1/16" ID, No 12 Gauge Steel.---from Googling AI :- 12-gauge mild steel is 0.1046 inches (or about 2.66 mm) thick.

From memory the spring is fitted on the upper section of the vertical clutch shaft -- above the clutch fork --to positively keep it down into the lower bore/bushing--maybe some one fitted it below the clutch fork by your description.

You can go to your local Cat Dealer Parts Department Manager and request the parts drawings from Caterpillar for the spring or indeed any Discontinued Parts.

If you can view a parts book image of the spring most any spring that fit the shaft with reasonable/suitable wire size and coils length, and/or remove the clutch top cover and see if you can view where, or not, the spring is fitted.

Hope this helps as I do not have a later D2 parts book.

Your experience may vary.

Cheers,

Eddie B.

That’s great info. Thank you! Pulling the cover to inspect is next on my to do list. Had to make room for it in the garage as I don’t want to tear into it sitting in the yard. 😂

Basically….I can hold the shaft down with my boot and the Cat drives about normal. Let pressure off it, the clutch position engagement “floats”. So I’m thinking the spring is my problem…Mostly.

i should have it apart this week to see exactly what’s going on. Thanks guys!

If the yoke is correctly engaged with the brass collar, it shouldn't be able to move (much) up and down because it's a reasonably snug fit (e.g. within 1/4" from memory - could be a bit off). When I worked on mine, my assumption was that the spring was there just to stop rattling

This is great info. Thanks fellas!