Copyright © 1996-Present. This website created, designed and maintained by Brian Miller.
Miscellaneous Small Engine and Garden Tractor Pulling Tips
& Tricks
(Information that don't fit in any other category.)
Where Science and Common Sense Come Together for Better
Performance
Please visit these other Brian Miller's websites:
A-1 Miller's Performance
Enterprises - Parts & Services Online Catalog |
Hot Rod Garden Tractor
and Mini-Truck Pullers Association
Optimized for 1024 x 768 screen resolution. To search for a word or phrase in any of my web sites, press CTRL and F to open the Find dialog box in your web browser. Although every effort has been taken to check the accuracy of information contained herein, I cannot assume responsibility for errors.
Using a Quality-Made Hitch with an Adjustable Drawbar on a Garden Pulling Tractor or Mini-Rod | Updated 1/5/16 Top of page
First of all, when a pulling
association's or club's sanctioning rules state that "the tractor shall have
no more than a 13" hitch height", this is worded wrong. It should read: "The
tractor shall have no more than a 13" drawbar height." The
"drawbar"
is the part where the hook (on the sled) fastens to. And the "hitch" is the
framework that's attached to the rear of the tractor. It contains the drawbar.
If you can keep from doing so, don't use a bolted-on-solid hitch with a non-adjustable drawbar or a one-piece, welded-on drawbar. It's not that the weld may break, but if you had change the drawbar height, choose to pull in another class or with another club that require a different drawbar height, or if you were to change tire size, deflate/inflate tire pressure, change the diameter of the front tires or as the rear tires wear, a hitch with an adjustable drawbar, you can easily and quickly reset the drawbar height accordingly. This will give your tractor a better advantage with the competition.
To be truly competitive, always run the highest drawbar height your clubs' rules allow. And the further rearward the drawbar is located, the more weight must be placed on the front of the tractor. But if the drawbar is too close to the rear axle, it'll be hard to control the front end from rearing up and down violently at times. Therefore, the best position for the drawbar is 6-1/2" to 8" rearward from the center of the rear axle. This should allow the front of the tractor to rise gently (if the tractor is weighted correctly), which should give the driver full control of the tractor. This measurement applies to all makes and models of garden tractors and for all classes of pulling tractors, from a basic stock to a fully modified.
Information Concerning Strength and Safety of the Pulling Hitch and Adjustable Drawbar Ê
When certain pulling
club's sanctioning rules state something like, "the pulling point may not
be more than 3/4 inches in depth," what they actually mean is, on the drawbar,
there must be no more (and no less, for strength) than 3/4" of metal between
inside rear of the hole and outside rearward edge of the drawbar.
Also, for strength and safety, and because most rules don't bother mentioning this, the drawbar itself should be made of minimum 1/2" thickness steel, and not aluminum!
But the upper and lower angle brackets should be made of either minimum 1/8" thickness mild steel or minimum 1/4" thickness 6061 aluminum.
-
When using steel angle brackets...
- The adjusting rods can be securely welded to the upper bracket only.
- The adjusting rods can be threaded through the upper bracket only and secured with a jam nut on each rod above the bracket.
- Through-holes can be drilled and two jam nuts can be used to secure the adjusting rods to the bracket.
- Through-holes can be drilled in the lower bracket and jam nuts are not necessary for the adjusting rods.
-
When using aluminum angle brackets...
- The adjusting rods can be threaded through the upper bracket only and secured with a jam nut on each rod above the bracket.
- Through-holes can be drilled and two jam nuts can be used to secure the adjusting rods to the bracket.
- Through-holes can be drilled in the lower bracket and jam nuts are not necessary for the adjusting rods.
-
Being 100% of the downward/rearward
[pulling] force is on the upper bracket, when fastening the aluminum bracket
to the tractor, install a wide, thick flat steel washer under each mounting
bolt head or nut (w/stud) to distribute the load and prevent either fastener
from being pulled through the aluminum or causing the aluminum to bend or
crack when under pulling strain.
How to Construct a Professional Pulling Hitch with an Adjustable Drawbar Ê
FYI: This entire assembly is
called the HITCH. The adjustable flat bar where the hook goes is called the
DRAWBAR.
This type of garden tractor pulling hitch with an adjustable drawbar is the most common and strongest ever used. It's low-cost and looks nice, too. It's the design that most professional pullers use, plus it's NQS legal. It will adapt to virtually any garden tractor as long as two pieces of angled steel can be fastened on the rear.
Specifications are:
- Use four grade 8 bolts or hardened steel studs with hardened steel nuts to fasten the hitch assembly directly over the existing IH Cub Cadet rear transaxle cover plate or on the rear of the frame of another make of garden tractor.
- Use either two minimum 1/8" thickness angle steel or minimum 1/4" thickness aluminum for the upper and lower support brackets. Each piece will need to measure 2" x 2" x 6-½" long.
- Use two 3/4" x 8" long steel threaded rods with 4 matching nuts to adjust the drawbar height. NOTE: Using nuts for the drawbar is more secure than using two 1/4" bolts threaded into the rear of the drawbar plate. Besides, due to metal fatigue from tightening and loosening, the [grade 8] 1/4" bolts have been known to break off flush in the drawbar.
- With steel angle brackets, the threaded rods can be either welded or fastened with jam nuts. But with aluminum angle brackets, jam nuts must be used.
- Use minimum 1/2" thickness x 2-½" wide x 6-½" long flat steel for the drawbar. Bore a 1-½" hole for the hook. Drill the hole offset 1/4" x 3/4", so they'll be 3/4" of metal at the rear of the drawbar for strength.
- Secure all three pieces of steel together and drill two 3/4" holes through all three of them for the adjusting rods. But before drilling the 3/4" holes through all three pieces of steel, it's best to space the drawbar at least 1/4" away from the rear cover plate, like it shows in the drawing. This means that the two 3/4" holes in the drawbar themselves must be drilled 1/4" offset. This prevents the drawbar from making contact with the rear plate when adjusting it.
- Drill the two adjusting holes in the drawbar with a 25/32" bit (slightly larger than 3/4") so it'll slide up and down without binding on the threaded rods.
- And that's it! You now have a professionally-constructed and safe-to-use pulling hitch with an adjustable drawbar!
How to Prevent the IH Cub Cadet Mechanical PTO Clutch/Starter Pulley from Loosening on the Crankshaft (Updated 3/17/15) Top of page
Tools and parts
required are: Drill press (or milling machine for better accuracy), 5/16"
drill bit (or 5/16"
countersink bit for better accuracy), 1/4"
transfer punch, two 5/16-18 UNC x 5/8" length Allen set
screws, and two 5/16-18 UNC jam nuts.
- Remove the pulley from the crankshaft. Be careful not to bend or damage it in any way.
- Remove the OEM set screws from the pulley and the keystock from the crankshaft. Set them aside for another project. They won't be needed for this fix.
- Reinstall the pulley on the crankshaft, position the outer edge of the hub exactly 1-1/8" from the end of the crankshaft, install one of the 5/8" length Allen set screws in the hub with the keyway and tighten it in the keyway slot.
- Going through the other set screw hole (that's located at the 3:00 position or 90° of the keyway slot), use the 1/4" transfer punch to place a mark on the crankshaft dead center of the hole. Don't go by the original indention mark on the crankshaft that the OEM set screw made, because if the pulley was loose, the indention may not be dead center with the hole.
- Remove the pulley and use the 5/16" drill bit and drill press to create an 1/8" deep hole (dimple) dead center of the punch mark.
- Reinstall the pulley on the crankshaft, install a 5/8" length Allen set screw in the hub and tighten it securely into the drilled hole.
- Install the other 5/8" length Allen set screw in the keyway slot and tighten it securely.
- Install the jam nuts on the set screws and tighten them securely to prevent the set screws (and pulley) from loosening overtime. NOTE: The 5/8" length set screws and jam nuts are short enough to not make contact with the pressure plate on the PTO clutch assembly.
Advertisement:
If you would like to purchase any of the parts or services
listed in this website, please contact A-1 Miller's Performance Enterprises
| 1501 W. Old Plank Rd. | Columbia, MO (Missouri) 65203-9136 USA |
 Phone: 1-573-256-0313 (shop)
| 1-573-881-7229 (cell). Please call Monday-Friday, except holidays, 9am
to 5pm, Central time zone. If no answer, please try again later. (When
speaking with Brian, please be patient because I stutter.) A-1 Miller's
shop is open to the public from 9am to 5pm, including weekends, except holidays.
Please call before coming so I'll be here waiting for your arrival.
 E-mail:
pullingtractor@aol.com.
Directions to our shop |
1501 West Old Plank Road, Columbia, MO - Google Maps or
Map of 1501 West Old Plank
Road, Columbia, MO by MapQuest. If you're the kind of person who
don't trust delivery/shipping companies (mis)handling your high-dollar and
fragile merchandise, you can make the long drive to
A-1 Miller's shop
to personally drop off and/or pick up your carburetor, clutch assembly, engine,
transaxle, tractor, etc. "The road to a friend's house (or shop) is never
long." (We're planning to relocate to other property with a bigger and better
shop so we can provide many more parts and services.)
Please click here to place
an order. |
|
 IH Cub Cadet Garden Tractor
Mechanical PTO Clutch Rebuild Kit. Fits Cub Cadet models 70, 71, 72, 73,
86, 100, 102, 104, 105, 106, 107, 108 (serial number 481999 & below),
109 (serial number 481999 & below), 122, 123, 124, 125, 126, 127, 128
(serial number 481999 & below), 129 (serial number 481999 & below)
and 147. OEM Cub Cadet part # 759-3490. $87.00 each, plus shipping
& handling. |
 IH Cub Cadet Garden Tractor
Mechanical PTO Clutch Rebuild Kit. Fits Cub Cadet models 86, 108, 109, 128
(serial number 482000 & up), 129 (serial number 482000 & up), 149
(serial number 481999 & below) and 169. Install both pressure springs
to prevent clutch slippage. OEM Cub Cadet part # 759-3489. $90.00
each, plus shipping & handling. |
 Carbon Button for IH Cub
Cadet Garden Tractor Mechanical PTO Clutch. OEM Cub Cadet part # IH-473483-R2.
$7.45 each, plus shipping & handling. |
 Metal Button for IH Cub
Cadet Garden Tractor Mechanical PTO Clutch. OEM Cub Cadet part # IH-473477-R3.
$10.75 each, plus shipping & handling. |
 New Insert Bearing with
Eccentric Locking Collar for IH Cub Cadet Garden Tractor Mechanical PTO Clutch.
Each kit includes set screw and jam nut. Bearing size: 1" i.d. x 2.04" o.d.
Fits all IH Cub Cadet with a mechanical PTO clutch.
|
 Clutch/Starter Pulley for
IH Cub Cadet Garden Tractor Mechanical PTO Clutch.
|
It's best to use a handy calculator
here
, have pencil and paper
available
, or have JavaScript
enabled in your web browser.
To convert CID into Cubic Centimeters (CC): (1 Cubic inch = 16.3870641 Cubic centimeters)
Multiply the CID by 16.39 = Cubic Centimeters.
Example: 262.37 (CID) x 16.39 = 4300 CC.
To convert CC back into CID: 1 Cubic centimeter = 0.0610237 Cubic inches.
How to Calculate the Compression Ratio of a Flathead or OHV Engine -
- Acquire a flat piece of Plexiglas slightly larger than the cylinder head, and drill a small hole in it where the combustion chamber of the head is.
- Acquire a large test tube with cubic centimeter increments.
- Fill the test tube with brake fluid.
- Make a note of how much brake fluid is in the test tube.
- Seal the Plexiglas over the cylinder head with the head gasket that's going to be used on the engine. (Use silicone sealer)
- Fill the combustion chamber with the brake fluid through the drilled hole.
- Make a note of how many cubic centimeters of brake fluid it took to fill the combustion chamber.
- Now calculate the cubic inches of the cylinder in the engine. Convert that figure into cubic centimeters.
- Finally, divide the cubic centimeters of the cylinder by the cubic centimeters in the combustion chamber. This should give the exact compression ratio.
- Identification of and Torque Specifications for the
Most Commonly Used Grades of Bolts -
NOTE: Use Standard Torque Settings When Specific Values Are Not Specified.
(C) = Coarse thread, (F) = Fine thread
| Hardness è | No lines = Grade 3
|
3 lines = Grade 5
|
6 lines = Grade 8
|
Stainless Steel / Special Alloy  |
| Bolt/Thread Size â |
Material: Low Carbon Steel. Tensile Strength: 85,000 p.s.i. (Low Strength) | Material: Medium Carbon Steel, Tempered. Tensile Strength: 120,000 p.s.i. (Medium Strength) | Material: Medium Carbon Alloy Steel, Quenched and Tempered. Tensile Strength: 150,000 p.s.i. (High Strength) | 18-8 [304] Stainless Steel |
1/4-20 (C) 1/4-28 (F) 5/16-18 (C) 5/16-24 (F) 3/8-16 (C) 3/8-24 (F) 7/16-14 (C) 7/16-20 (F) 1/2-13 (C) 1/2-20 (F) 9/16-12 (C) 9/16-18 (F) 5/8-11 (C) 5/8-18 (F) 3/4-10 (C) 3/4-16 (F) |
70 in. lb./ 6 ft. lb. 85 in. lb./ 7 ft. lb. 150 in. lb./13 ft. lb. 165 in. lb./14 ft. lb. 260 in. lb./22 ft. lb. 300 in. lb./25 ft. lb. 35 ft. lb. 45 ft. lb. 50 ft. lb. 70 ft. lb. 75 ft. lb. 100 ft. lb. 110 ft. lb. 140 ft. lb. 150 ft. lb. 200 ft. lb. |
115 in. lb./10 ft. lb. 140 in. lb./12 ft. lb. 250 in. lb./21 ft. lb. 270 in. lb./23 ft. lb. 35 ft. lb. 40 ft. lb. 55 ft. lb. 75 ft. lb. 80 ft. lb. 105 ft. lb. 125 ft. lb. 165 ft. lb. 180 ft. lb. 230 ft. lb. 245 ft. lb. 325 ft. lb. |
165 in. lb./14 ft. lb. 200 in. lb./17 ft. lb. 350 in. lb./29 ft. lb. 30 ft. lb. 50 ft. lb. 60 ft. lb. 80 ft. lb. 105 ft. lb. 115 ft. lb. 165 ft. lb. 175 ft. lb. 230 ft. lb. 260 ft. lb. 330 ft. lb. 350 ft. lb. 470 ft. lb. |
14 ft. lb. 17 ft. lb. 29 ft. lb. 35 ft. lb. 58 ft. lb. 69 ft. lb. 98 ft. lb. 110 ft. lb. 145 ft. lb. 160 ft. lb. 200 ft. lb. 220 ft. lb. 280 ft. lb. 310 ft. lb. 490 ft. lb. 530 ft. lb. |
How To Cut New Threads, the Correct and Professional Way | Top of page
When cutting new threads in
a drilled hole for a bolt, stud or screw, to prevent breaking off a [plug]
tap in the hole (this can be a nightmare!), it's best to start the thread
cutting process with a (preferably new)
TAPER hand tap, then the threads can be cut deeper with
a (preferably new)
PLUG hand tap. If it's a blind hole (a hole that is blocked-off
or not open at one end, such for mounting an exhaust header flange), the
threads will go deeper with a plug tap for installation of the mounting bolt.
(A through-hole is a hole that is open at either end, such as in plate steel.)
And a
BOTTOM hand tap is useful when the threads needs to go
deeper than the plug tap can provide.
Refer to the chart(s) below Ê for the correct size drill bit for the hole to be threaded. After drilling the hole, start the thread cutting process with a (preferably new) TAPER tap. For best thread cutting results, use WD-40 when cutting threads in aluminum, and use thread cutting oil, automatic transmission fluid (ATF) or power steering fluid (10 weight hydraulic oil) when cutting threads in cast iron or steel.
- To professionally create new threads, start the [taper] tap perpendicular, and not crooked (over to one side), with the hole. If a taper tap is mistakenly started crooked in the hole, in most cases, it'll straighten itself out with the hole as the cutting process continues. A plug tap may not do this.
-
For a blind hole with right-hand threads, gently rotate the tap clockwise
about 1/2 turn to cut the threads, then
back it off counterclockwise 
about 1/4 turn.
This will loosen and somewhat dislodge the metal cuttings from the flutes
in the tap (open spaces between the cutting teeth). If the tap is difficult
to back off, DO NOT FORCE IT, especially a small tap! Instead, with the tap
in the hole, use (150± psi) compressed air to clear out the majority
of the metal cuttings from the hole (wear
safety glasses!), then GENTLY rotate the tap counterclockwise
until it rotates freely and comes out of
the hole. Again, use compressed air to clear out the metal cuttings from
the hole.
- Gently and carefully cut the remaining threads until the tap bottoms out in the [blind] hole. Repeat step #2 several times for better results with a bigger tap, and less chance of breaking off a smaller tap in the hole. Use less muscle and more patience when working with smaller taps!
- Use caution and be aware of the depth of a blind hole when the tap bottoms out! If it's a shallow blind hole, judge by the hole's depth to determine where the tap will bottom out.
-
Then use a (preferably new) PLUG hand tap, and repeat the 1/2 turn clockwise
and 1/4 turn counterclockwise
until the new threads are cut all the way
in or through the hole. Return To Previous
Paragraph or Website
Removing a Broken-Off
Tap From a Hole - A threading tap that has broken off in an engine block
or metal casting can be very difficult to remove. About all I can tell you
is to either take your block to a reputable machine shop to have the tap
removed, or go here and try to do it yourself:
https://www.google.com/?gws_rd=ssl#q=removing+broken+tap+from+hole.
Actually, before cutting new threads, it's ALWAYS best to use a TAPER hand
tap, and clean out existing threads as the tapping process progresses. If
used correctly, a TAPER tap is less likely to break off in the hole.
Tap and Drill Chart - Inch Sizes Only
|
|
Tap and Drill Bit Chart - Inch, Special Inch and Metric Sizes
|
|
National Pipe Tapered Tap Chart (Recommended tap drill to use for 75% thread depth.)
| To Cut This Size Pipe Threads | Outside Diameter of Pipe | Use This Size Drill Bit | Closest Fractional | Decimal Inches |
| 1/16-27 NPT | 0.313" (5/16") | D | 1/4" | .246" |
| 1/8-27 NPT | 0.405" (13/32") | R | R or 11/32" | .339" |
| 1/4-18 NPT | 0.540" (35/64") | 7/16" | 7/16" | .4375" |
| 3/8-18 NPT | 0.675" (43/64") | 37/64" | 67/64" | .5781" |
| 1/2-14 NPT | 0.840" (27/32") | 45/64" | 45/64" | .7031" |
| 3/4-14 NPT | 1.050" (1-3/64") | 59/64" | 59/64" | .9219" |
| 1-11 1/2 NPT | 1.315" (1-5/16") | 1-5/32" | 1-5/32" | 1.1562" |
| 1-1/4-11 1/2 NPT | 1.660" (1-21/32") | 1-1/2" | 1-1/2" | 1.5000" |
| 1-1/2-11 1/2 NPT | 1.900" (1-57/64") | 1-47/64" | 1-47/64" | 1.7344" |
| 2-11 1/2 NPT | 2.375" (2-3/8") | 2-7/32" | 2-7/32" | 2.2188" |
For performance testing engines
up to 200hp at speeds up to 12,000 RPM. The only engine dyno service in Missouri
for Kohler pulling engines! Fully operational and 100% accurate, customers
can rent dyno time, fine tune and make adjustments or changes to their engines
to gain maximum horsepower and torque, and print-out the results so their
tractor(s) will be truly competitive on the track. NOTE: A fresh-built
engine may not produce full power until it's broke-in. This is when the valves
wear-in with the seats to completely seal in the compression. The rings will
likely hold the compression, but the valves may leak slightly until they
wear into the seats. This is normal for all engines and may take several
hours or pulls to happen, then the valves will be able to hold full compression.
Lots of pullers tell me after I've built their engines that it seems to pull
stronger every time they pull it.
-
Coming Soon - Detailed
Illustrated Plans on How to Construct a Professional Pull-Back Garden Tractor
Pulling Sled, and a Motorized/Self-Propelled Garden Tractor Pulling
Sled. FYI - My professionally-built
motorized/self-propelled pulling sled, Track Master (click the picture to
the right to see a larger image of my sled), is the only one I've ever built
and I got it right the first time, with very few changes that had to be made
to it. I guess I'm just one of those kind of guys that knows what he's doing.
Pullers really like pulling my sled, too. They say it's the best sled they've
ever pulled. (Not bragging, just stating the truth.) By the way - Track Master
sled is engineered so well (by Brian Miller), that other sled builders/owners
have copied my well thought-out and proven design. Anyway, I have lots of
work to do in my shop and I work on the sled plans in my spare time. As soon
as my plans with an inventory list of parts to use are perfected, I'll post
the update in my websites. Remember - Perfection takes time. If it's worth
having, it's worth waiting for. Also, I plan to acquire a bigger shop and
I may build high quality garden tractor pulling sleds in the future to offer
for sale. Please call me at 573-256-0313 (shop) or 573-881-7229 (cell), or
email me at