Problem: Loose steering caused by worn hole in left Steering Knuckle/Arm;
Here is Pete's Solution: Install a Taper Pin Kit
Last Revised: October 20, 2023
Taper Pin Kit in Place
Here's how the parts fit
Home
My Cub Main Page
Blacksmithing
My Shop
Contact Us
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 may offer some other choices:
-Replace the pin
-Put a bolt in the hole instead
-Drill out the hole and go to a bigger pin or bolt
-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.
Note!!: If the hole has been drilled out to more than 3/8", contact me. I may have a special solution for you.
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.
Remember that you should NEVER turn a reamer backwards. If you can't simply pull it straight out of the hole to
check your fit, turn it clockwise a couple of turns while pulling gently outward on it.
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 3/4 of an inch deep..
This allows me to secure the taper pin in the Knuckle/Arm hole once it is in place.
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 3/4" long 1/4-20 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 all five of my own tractors, and I have done it to two Cubs that my boys
own.
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 #7 taper pin reamer currently costs anywhere from about $22.00 to $45.00
each. 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 (2002). Cut the pin to the 2 1/2" 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:
My "One Pin Kit"
Cost Using All New Parts:
Left Steering Knuckle (spindle) $97.02
Arm $62.52
Pin, 5/16" X 2" (est.) $ 1.00
--------
Total Parts cost (SRP,circa 2012,) $160.54
Cost Using My One Pin Kit:
Taper Pin Approach:
PreDrilled #7 X 2 1/2" Taper Pin $ 9.00
Bolt, 1/4-20 X 3/4" Grade 5 $ .50
Spacer (7/16-14 nut) $ .50
Hand Reamer, #7 Taper Pin $27.00
--------
Total Parts cost (SRP, Pete Stanaitis, circa 2020) $37.00
I will sell the kit with one pin for $37 plus $6.00 S& H (43.00 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 a customer about its condition.)
$160.54 / $43.00 makes it 3.7 to 1 in favor of my taper pin method.
My "5 Pin Kit":
If you have several machines around, or even 2 of them, consider:
The Five Pin Kit:
5 PreDrilled #7 X 2 1/2" Taper Pins $ 35.00
5 Bolt, 1/4-20 X 3/4" Grade 5 $ 2.00
5 Spacer (7/16-14 nut) $ 2.00
1 Hand Reamer, #7 Taper Pin $ 27.00
--------
Total Parts cost (SRP, Pete Stanaitis, circa 2020) $66.00
I will sell this 5 Pin Kit for $66.00 plus $7.00 S& H ($73.00 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 a customer about its condition.)
So, $802.70 for 5 sets of new parts vs. $73.00 for taper pin method; 10.99 to 1 in favor of my taper pin approach.
If you want to order by US mail, send check or money order to:
Pete Stanaitis
2476 10th Av W
Baldwin WI 54002
And feel free to email me at:
spaco@baldwin-telecom.net
if you have any questions.
Here are links to a few other things that are Cub-Related, one way or the other:
-My Drive-on Grease Rack makes servicing easy
-The rear Drive Shaft drive pins are hard to replace- add a little hole
-The "Unofficial" Cub Cadet site
-Trackster.com, another off-road vehicle