Please visit these other Brian Miller's websites: A-1 Miller's Performance Enterprises - Parts & Services Online Catalog | Miller's ATV, UTV and Local/Stock Garden Tractor Pulling Sled Rental | Hot Rod Garden Tractor and Mini-Truck Pullers Association |
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
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The Importance and Safety of Having Wheelie Bars on a Pulling Tractor (Updated 11/4/05) Top of page
If a pulling tractor is going
to run a 13" drawbar height with 26x12.00-12 tires, it must have wheelie
bars properly installed, even if a club or pull site doesn't require them.
Because a pulling tractor can flip back so quickly, without warning. The
rear tires are rotating in one direction, which forces the tractor to want
to rotate in the opposite direction. ("For every action, there's an equal
and opposite reaction." -
Newton's third law of motion.) So for safety sake, it's
best to have wheelie bars installed for pulling regardless of the height
of the drawbar or tire size. Wheelie bars are sometimes referred to as a
"no-tip device." Wheelie bars are one of the easiest things to install on
a pulling tractor. Only an idiot or someone with a death wish would pull
a tractor without wheelie bars!
The pads or wheels for the ground contact needs to be of adequate size too, to prevent from sinking into soft earth. The pads need to be a minimum of 3" square x 1/8" thickness and wheels need to be a minimum of 4" diameter x 1" wide. Most pullers prefer to use wheels on the wheelie bars. They allow the tractor to gain an inch or two because they "roll." The pads on the other hand scrape on the ground and doesn't allow the tractor to get much further. And it's a good idea for stock tractors to run a 10" drawbar height anyway to prevent breaking a stock rear end.
For best stability of the tractor when the front end raises upward, most club's rules state that the bottom of the wheelie bar wheels or skid plates are supposed to a maximum of 5" from the ground. And the rear of the wheelie bar wheels or skid plates are supposed to be a minimum of 5" from the tread of the rear tires. Scroll down to see drawing for a better explanation. Check out this YouTube link: When it's important to have wheelie bars on a pulling tractor!
For safety reasons, make your wheelie bar bracket material rigid and not spring-loaded. They must be made of heavy wall (minimum 1/8" thickness) tubing and reinforced for strength. Also, bolt on the wheelie bar brackets and don't weld them to the frame. So they can be adjusted if necessary. See the pictures below Ê for what typical wheelie bar brackets look like:
NOTE: The wheelie bar brackets shown above were
fabricated by the individual who owns each tractor.
And be aware when using flat
aluminum wheelie bar braces. If the tractor were to stop suddenly on the
track, and the sled bumps the rear of the tractor, the braces may bend to
the side from the impact. And straightening them so they'll look original
again is almost impossible. Therefore, we think it's better to use 1-1/2"
x 1-1/2" x 1/8" wall square tubing as wheelie bars. When the sled bumps wheelie
bars made of heavy wall square tubing, the whole rear of the tractor will
move sideways slightly, and the wheelie bars won't suffer any damage.
Advertisement:
If you would like to purchase any of the parts or services listed below
Ê, or virtually any product or service mentioned 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.
Please click here
to place an order.
|
How to set the wheelie bars for proper height so the front end won't be too high or too low when the front tires comes off the ground:
- Install the front and rear tires that you're going to use at the pulls on the tractor.
- Raise the front of the tractor (using a hoist or ramps) until the bottom of the front tires are about 16" off the ground.
- Set the wheelie bars w/wheels or skid pads on the ground.
- Mark and drill holes in the frame or transaxle to fasten the wheelie bar brackets.
- Use 3/8" diameter grade 8 bolts to fasten the wheelie bars!
About Rear Safety Bumpers -
When a high speed garden tractor gets going down the track really good, and all of a sudden it's engine stalls and the tractor comes to a complete stop, what's going to happen? Chances are the sled will bump the rear of the tractor. Most sled operators can't put the brakes on in time or react fast enough because this can happen so quickly. Therefore, it's a good idea to install a couple of heavy-duty rear "bumpers" mounted on or incorporated into the wheelie bar brackets located a minimum of 6" above the wheels or pads. (Most club's rules and regulations will or should specify the location.) These bumpers will keep the sled from possibly getting up on top of the rear tires, causing damage to the tractor and/or injury to the driver. And the bumpers will prevent the pull chain from getting "wrapped" around one of the rear tires should the tractor go sideways to the extreme.
All tractor pullers, despite their age, needs to be educated on safety requirements and proper operation of a pulling tractor. Because many of them, when the tractor they're sitting on is hooked to the sled, will rev it up and give it all it's got, and they'll do whatever it takes to win. Some even get injured by doing so. They think it's a "no-holds-barred" contest.
We've seen a few garden tractor pullers would start to pull the sled (not our sled), when all of a sudden it would flip backwards and sometimes the puller would hit the back of their head on the front of the skid pan dirt shield because no wheelie bars were installed. They weren't seriously injured though. But it's scary to actually witness something like that! It's not a funny thing and certainly not part of the show!
We were at a pull several years ago [at a now defunct pulling club that was based in central Missouri], when an inexperienced person (adult) on a stock garden tractor caught on fire while pulling the sled [not our sled] down the track when all of a sudden the front of his tractor reared up and stood on end. What caused this is the tractor had 26-12.00x12 lug tires, about a 16" drawbar height and no wheelie bars. It also had a loose-fitting gas cap, a full tank of gas, which was positioned above the engine, and the battery, which was positioned between the gas tank and steering column, wasn't fastened down. When the tractor stood on end, the gas cap fell off, spilling gas onto the battery and onto the driver. Then the battery tipped back, shorting out the posts against the metal steering column support, igniting the fuel. It was a horrible sight! The flames were extinguished and the puller had to be air-lifted to the nearest hospital with a burn unit. He recovered from his injuries, but to this day he has scars on his chest and groin area to remind him of that horrible day at a tractor pull when he was just trying to have some fun with his friends. Not to mention the mental scars it left, too.
An official of that particular pull should have inspected that tractor and all the other tractors for safety, and not allow the puller to participate if the tractor wasn't legal or if an adjustment wasn't made.
Tell your friends and family about this story. And tell them to install sturdy wheelie bars, whether if they feel they need them or not, or if the rules require them or not. Remember - friends don't let friends pull without wheelie bars (and other safety equipment). And NEVER allow a young person to participate in a pulling event without wheelie bars (and of course, other safety equipment) properly installed and maintained.
We've been to a lot of garden
tractor pulls over the years and noticed that some tractors leak fuel in
places where a fuel leak shouldn't be. Therefore, we think that safety
inspections needs to include checking the fuel lines for dry-rotting, cracks,
fuel leaks, loose fittings, etc. (The tractors should have sturdy wheelie
bars, too.) The inspectors needs to grab hold of the fuel line(s) with their
hand and wiggle it around and slightly jerk on it to check for durability.
This is important. Especially in a kid's class. Don't wait until an issue
becomes a problem, and then turn into a catastrophe. If pullers would build
their tractors right to begin with and maintain them properly, there wouldn't
be any injuries, fires, or fear of a fire.
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.
| If you would like to purchase any of the parts or services listed below
Ê, or virtually any product or service mentioned 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.
Please click here
to place an order. |
|
 Professionally
Constructed Pulling Hitch Assemblies for Garden Pulling Tractors and 1,500
lb. Small Wheel Mini Rods. This is the design that's NQS legal, and
preferred by professional pullers everywhere!
Specifications include:
|
|
 Drawbar only for
build-it-yourself garden pulling tractor hitch. Comes with a 1-1/2" hole
for hook. Edge of 1-1/2" hole is spaced 3/4" from rear of drawbar for maximum
strength and safety. No holes for adjustment rods. Customer locates and
drills own holes. Dimensions: 6" wide x 2-1/2" depth x 1/2" thickness.
Made of mild steel. An original concept by Brian Miller. Accept no copycat
parts!
|
 Drawbar only for
build-it-yourself garden pulling tractor hitch. Comes with a 1-1/2" hole
for hook. Edge of 1-1/2" hole is spaced 3/4" from rear of drawbar for maximum
strength and safety. Has two 25/32" holes for 3/4" adjustment rods for
easier adjustment. Dimensions: 6" wide x 2-1/2" depth x 1/2" thickness.
Made of mild steel. An original concept by Brian Miller. Accept no copycat
parts!
|
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 below
Ê, or virtually any product or service mentioned 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.
Please click here
to place an order. |
|
 New Insert Bearing
with Eccentric Locking Collar. 1" i.d. x 2.04" o.d. Fits all IH Cub Cadets
with mechanical PTO clutch.
|
 Cub Cadet PTO Clutch/Starter
Pulley.
|
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 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! Now set up and fully operational, customers can
rent dyno time, fine tune and make adjustments or changes to their engines
for 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.
-
