Problem: Loose steering caused by worn hole in left Steering Knuckle/Arm;

Last Revised 9/6/2008 (Reamer prices have gone up!)

Discussion:

I'm not a collector or real restorer of these things, but I do have 6 of them and about 6 acres to mow. As the tractors get older, the whole steering system loosens up, as we all know. There are good, no-cost or reasonably priced solutions for all the causes of looseness, except for the looseness at the point where the left “Steering Knuckle” is connected to the “Arm” by a 5/16" roll pin. I have talked to several dealers about what to do to correct this. They would mostly like to sell a new left Steering Knuckle and arm.
But they will offer some other choices:
-Replace the pin
-Put a bolt in the hole instead
-Drill out the hole and go to a bigger pin
-Weld the Steering Knuckle to the arm (ick!!!)
- etc.

I looked thru the unofficial Cub Cadet website archives for a while and found one reference to the problem, but nothing on solutions. I probably just didn't look far enough. So after trying all of the above solutions with not much success, I developed my own. And, if I do say so myself, it is a permanent, no compromise method of solving the problem for good! I was thinking of trying to find some way of selling my idea to dealers, but, what the heck; I am retired and not starving to death so:

The problem:
With age, both the hole in the steering knuckle and the hole in the collar of the arm wear enough that the 5/16" roll pin comes loose, sometimes enough to fall out. Even if it doesn't fall out, this looseness can easily cause 1/4 to 1/2 a turn of slop in the steering system all by itself. To complicate the problem, some owners have drilled out the original 5/16" hole to 3/8 and put in a 3/8" bolt. This usually isn't much help, since standard drill bits usually drill somewhat oversize holes anyway and so the problem doesn't really go away.

My solution:
I replace the original straight 5/16 roll pin with a specially prepared #7 taper pin. This requires drilling out the existing hole and reaming it so the taper pin makes a perfect fit in the hole.

Here's how I do it:
Jack up the left front of the tractor and remove the left front wheel. With the steering wheel in the straight ahead position, remove the pin (or whatever happens to be in the hole now).
With the arm still in place on the steering knuckle, drill and ream the hole from front to rear as follows:
I drill and ream the assembly (with the arm in place on the steering knuckle) for a #7 taper pin that is about 2 1/2" long. I use a hand reamer. There are tables available for the proper drill bits and depths to prepare the hole for the reamer. I drill the hole all the way through with a 23/64” or a letter T drill bit and then drill about 5/8" through (from the front)with a 3/8” bit.
I then ream deep enough so that the small end of a taper pin will stick out of the hole at least 1/16”. Use lots of cutting oil on the reamer. Clean out hole and check pin for fit every 20 or 30 cranks of the reamer.
I have made a fixture that allows me to drill and tap the small end of the #7 taper pins to 1/4-20 for about ľ of an inch deep.. Once the hole has been reamed, I simply push the taper pin into the hole, tap on the big end of the pin with a light hammer to seat it firmly, and then bush out the excess pin that comes thru the arm's collar with an oversize nut ( 7/16” nut works).
I screw a ľ” long Ľ-20 bolt into the tapped hole in the end of the taper pin and tighten it up.

The beauty of the this process is that it even works for those cases where the hole has been drilled out to 3/8" and even if wear has occurred at that size. I have done this to four of my own tractors over a three year period, and I just did it my two newest acquisitions this month. I use my Cub Cadets a lot! Lawn mowing takes 6 hours, with two tractors going at a time. And I have had no problems at all with the modification. It destroys nothing. It isn't a compromise. And, if any wear does occur, just tighten up the 1/4-20 bolt a bit. If the bolt breaks, it is easy to drive the pin out and replace it. If EXCESSIVE wear did occur, I’d just remove the taper pin and take a couple more turns with the reamer.
You CAN drill and tap the small end of the taper pin without a fixture, with a little care. An “Import” #7 taper pin reamer now costs $20.00 or more each, (MSC catalog or call 1-800-645-7270). The #7 taper pins are a little hard to find. I got mine from Field Fastener in Rockford, Illinois. Recently I noticed that you can buy individual #7 taper pins in plain steel from MSC, too. But you need to buy the 4” long size in order to buy one pin for $0.84 (2002). Cut the pin to the 2 ˝” length FROM the big end, drill and tap the small end 1/4-20.
Anyway, there it is. If you don’t want to go looking for the special parts and tools yourself, I will sell the following kits, below. -Pete Stanaitis

Calculations for efficacy of taper pin repair vs new parts replacement:
New Parts Approach:
Left Steering Knuckle (spindle) $43.87
Arm $23.86
Pin, 5/16” X 2” (est.) $ 1.00
--------
Total Parts cost (SRP,circa 2000, Case/IH) $68.23

Taper Pin Approach:
PreDrilled #7 X 2 ˝” Taper Pin $ 5.00
Bolt, Ľ-20 X ľ” Grade 5 $ .50
Spacer (7/16-14 nut) $ .25
Hand Reamer, #7 Taper Pin $22.00
--------
Total Parts cost (SRP, Pete Stanaitis) $27.75

I have marked up the components to account for stocking them, profit, mfg, etc.

I will sell the kit with one pin for $35 plus $4.00 S&H (39.00 total), with no returns on the reamer. I would be concerned that a returned reamer might be damaged and I don’t want to get into any “contest” with the customer about its condition.

1.95 to 1 in favor of the taper pin method.

Five Pin Kit:
5 PreDrilled #7 X 2 ˝” Taper Pins $ 25.00
5 Bolt, Ľ-20 X ľ” Grade 5 $ 2.50
5 Spacer (7/16-14 nut) $ 1.25
1 Hand Reamer, #7 Taper Pin $ 22.00
--------
Total Parts cost (SRP, Pete Stanaitis) $50.75

I will sell this kit for $64.00 plus $5.00 ($69.00 total) S&H

So, $341.15 for 5 sets of new parts vs. $64.00 for taper pin method; 5.3 to 1 in favor of the taper pin approach.
The prices from the Cub Cadet dealer have probably increased since I got them several years ago, so the savings is bound to be higher than what I show here.

If you want to order, send check or money order to:
Pete Stanaitis 2476 10th Av Baldwin WI 54002

Here are links to a few things that are Cub-Related, one way or the other:
Check 'em out and don't forget to sign our Guest Book!

-My Drive-on Grease Rack makes servicing easy

-The “Unofficial” Cub Cadet site

-The rear Drive Shaft drive pins are hard to replace- add a little hole

-Trackster.com, another off-road vehicle

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