Miscellaneous Small Engine and Garden Tractor Pulling Tips
& Tricks
(Information that don't fit in any other category.)
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Identification and Torque Specifications for the Most Commonly Used Grades of Bolts |
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Fractions, Numbers, Letters, Decimals and Metric Equivalents |
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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 wording is
not accurate! It should read: "The tractor shall have no more than a 13"
drawbar/hitch
height." The
"drawbar" is a separate part that's supported by the framework
on the rear of the tractor. But if the drawbar is non-adjustable and is fastened,
welded to or part of the tractor/vehicle frame, then it's called the hitch,
as in
receiver hitch, to tow a trailer.
Anyway, if you can keep from doing so, don't use a non-adjustable, bolted-on-solid or welded-on hitch. It's not that the weld may break, but if you have to change the height height, or pull with another club that require a different hitch height, or if you were to change tire size, deflate/inflate tire pressure, change the diameter of the front tires, the hitch height can't be changed (lowered) for legality of the club's pulling rules. Therefore, with a fully adjustable drawbar, you can easily and quickly reset the drawbar height according to the club's rules. This will give your tractor a better advantage with the competition, and not be disqualified due to the hitch being too high (above 13" or whatever the club's rules allow).
To be truly competitive, always run the highest drawbar height your clubs' rules allow. But if the driver of a tractor is a large person, then lower the drawbar height to 12". Doing this will place more weight toward the front of the tractor so the driver will have better control while going down the track. 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 uncontrollably 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 with an 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.
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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.
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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.
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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, extremely strong and safe to use pulling hitch with an adjustable drawbar!
Identification and Torque Specifications for the Most
Commonly Used Grades of Bolts [Top of Page]
NOTE: Use Standard Torque Settings When Specific Values Are Not Specified.
(C) = Coarse thread, (F) = Fine thread
| Hardness of Bolts è | No lines = Grade 3
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3 lines = Grade 5
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6 lines = Grade 8
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Stainless Steel or 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 Professionally Cut New Threads [Top of Page]
New threads in a drilled
hole (of the correct size) should ALWAYS be made with a (preferably new)
TAPER hand tap to prevent the possibility of breaking the
tap off in the hole! (This can be a nightmare, especially with an expensive
and/or non-replaceable part!) Taper taps are self-aligning, cut new threads
easily, much quicker and require less effort than plug taps. Then deeper
threads can be made with a PLUG or BOTTOM tap. (Care should still be taken
whenever cutting new threads, especially with smaller size taps.) Most hardware
stores do not stock taper (or bottom) hand taps. They keep mostly plug taps
in stock. Therefore, taper taps will need to be purchased online, such as
eBay or Amazon. And the only threading dies with tapered threads available
are for NPT pipe threads. These have a different pitch than any straight
bolt threads.
For best thread cutting results, use WD-40 when cutting new threads in aluminum, and when cutting new threads in cast iron or [mild] steel, use thread cutting oil, automatic transmission fluid (ATF) or power steering fluid (which is 10 weight hydraulic oil).
- 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.
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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.
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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.
- Refer to the Drill and Tap Chart below to find the correct size drill bit to use for any particular hole to be threaded.
Removing a Broken-Off Bolt from a Hole - As far as removing a broken-off bolt in an engine block or cylinder head for an exhaust flange is concerned, I have never had any luck with tapered spiral-fluted screw extractors. In my experience, all they do is thread itself deep into the drilled-out broken-off bolt and expand the bolt, making it harder, if impossible, to remove. Instead, what to do is grind flat any protruding metal of the broken-off bolt/stud, then precision center-drill into the broken-off bolt/stud with a short length drill bit or a centering bit (to prevent wobbling of the bit) as a pilot hole, then bore into the bolt/stud with the appropriate size drill bit, then re-thread the hole with a TAPER hand tap of the appropriate size, and then finish re-threading it with a PLUG tap.
Removing a Broken-Off Hand Tap from a Hole - A threading tap that has broken-off in an engine block or metal casting can be very difficult to remove. A HSS annular cutter could be used because these have a hollow center hole that can cut around the broken-off tap, Use an annular cutter with the same size center hole as the [broken-off] tap. Then the [bored] hole can be welded up, drilled and new threads made. Or Google: removing broken tap from hole, or have an experienced and reputable machine shop remove the broken-off tap. [Return To Previous Paragraph or Website]
Drill and Tap Chart for Inch Sizes
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Drill and Tap Bit Chart for Inch, Special Inch and Metric Sizes
[Top of Page]
NOTE - There's three different type of drill bits - fraction, number and
letter. Actually, there's four, including metric. Use the one that's closest
to the size hole that needs to be drilled.
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Drill and Tap Chart for National Pipe Tapered (NPT) Threads | NOTE - Recommended tap drill to use for 75% thread depth. [Top of Page]
| To Cut This Size Pipe Threads | Use This Size Drill Bit / Closest Fractional / Decimal Inches | Outside Diameter of Pipe |
| 1/16-27 NPT | D / 1/4" / .246" | 0.313" (5/16") |
| 1/8-27 NPT | R / 11/32" / .339" | 0.405" (13/32") |
| 1/4-18 NPT | 7/16" / .4375" | 0.540" (35/64") |
| 3/8-18 NPT | 37/64" / .5781" | 0.675" (43/64") |
| 1/2-14 NPT | 45/64" / .7031" | 0.840" (27/32") |
| 3/4-14 NPT | 59/64" / .9219" | 1.050" (1-3/64") |
| 1-11 1/2 NPT | 1-5/32" / 1.1562" | 1.315" (1-5/16") |
| 1-1/4-11 1/2 NPT | 1-1/2" / 1.500" | 1.660" (1-21/32") |
| 1-1/2-11 1/2 NPT | 1-47/64" / 1.7344" | 1.900" (1-57/64") |
| 2-11 1/2 NPT | 2-7/32" / 2.2188" | 2.375" (2-3/8") |
| Tap Size | Drill This Size Hole | Drill This Size Hole | Basic Major Millimeter Diameter | Basic Major Inch Diameter | Millimeters Per Thread |
| M1.6 x 0.35 | #55 | 1.25mm | 1.6mm | .063" | .35 |
| M2 x 0.4 | #52 | 1.6mm | 2mm | .0787" | .4 |
| M2.5 x 0.45 | #46 | 2.05mm | 2.5mm | .0984" | .45 |
| M3 x 0.5 | #39 | 2.5mm | 3mm | .1181" | .5 |
| M3.5 x 0.6 | #32 | 2.9mm | 3.5mm | .1378" | .6 |
| M4 x 0.7 | #30 | 3.3mm | 4mm | .1575" | .7 |
| M5 x 0.8 | #19 | 4.2mm | 5mm | .1969" | .8 |
| M6 x 1 | #8 | 5mm | 6mm | .2362" | 1 |
| M8 x 1.25 | H | 6.8mm | 8mm | .315" | 1.25 |
| M8 x 1 | J | 7mm | 8mm | .315" | 1 |
| M10 x 1.5 | R | 8.5mm | 10mm | .3937" | 1.5 |
| M10 x 1.25 | 11/32" | 8.8mm | 10mm | .3937" | 1.25 |
| M11 x 1.5 | 3/8" | 9.5mm | 11mm | .433" | 1.5 |
| M11 x 1.25 | U | 9.75mm | 11mm | .433" | 1.25 |
| M12 x 1.75 | 13/32" | 10.2mm | 12mm | .4724" | 1.75 |
| M12 x 1.25 | 27/64" | 10.8mm | 12mm | .4724" | 1.25 |
| M14 x 2 | 15/32" | 12mm | 14mm | .5512" | 2 |
| M14 x 1.5 | 1/2" | 12.5mm | 14mm | .5512" | 1.5 |
| M16 x 2 | 35/64" | 14mm | 16mm | .6299" | 2 |
| M16 x 1.5 | 37/64" | 14.5mm | 16mm | .6299" | 1.5 |
| M18 x 2.5 | 39/64" | 15.5mm | 18mm | .7087" | 2.5 |
| M18 x 1.5 | 21/32" | 16.5mm | 18mm | .7087" | 1.5 |
| M20 x 2.5 | 11/16" | 17.5mm | 20mm | .7874" | 2.5 |
| M20 x 1.5 | 47/64" | 18.5mm | 20mm | .7874" | 1.5 |
| M22 x 2.5 | 49/64" | 19.5mm | 22mm | .8661" | 2.5 |
| M22 x 1.5 | 13/16" | 20.5mm | 22mm | .8661" | 1.5 |
| M24 x 3 | 53/64" | 21mm | 24mm | .9449" | 3 |
| M24 x 2 | 7/8" | 22mm | 24mm | .9449" | 2 |
| M27 x 3 | 15/16" | 24mm | 27mm | 1.063" | 3 |
| M27 x 2 | 1" | 25mm | 27mm | 1.063" | 2 |
Decimals of | Decimals of | Decimals of MM an inch | MM an inch | MM an inch ------------------+----------------------+-------------------- .1 = .00394" | 1. = .03937" | 15. = .59055" .2 = .00787" | 2. = .07874" | 16. = .62992" .3 = .01181" | 3. = .11811" | 17. = .66929" .4 = .01575" | 4. = .15748" | 18. = .70866" .5 = .01968" | 5. = .19685" | 19. = .74803" .6 = .02362" | 6. = .23622" | 20. = .78740" .7 = .02756" | 7. = .27559" | 21. = .82677" .8 = .03149" | 8. = .32496" | 22. = .86614" .9 = .03543" | 9. = .35433" | 23. = .90551" 10. = .3937" | 12.7 = .500" | 24. = .94488" 11. = .43307" | 13. = .51181" | 25. = .98425" 12. = .47244" | 14. = .55118" | 25.4 = 1.000" |
NOTE: There's three different type of drill bits - fraction, number and letter. Actually, there's four, including metric. Use the one that's closest to the size of hole that needs to be drilled.
Fraction/| | | Fraction/| | | Fraction/| | Number/ | Decimal | MM | Number/ | Decimal | MM | Number/ | Decimal | MM Letter | | | Letter | | | Letter | | ----------------------------+----------------------------+---------------------------- 1/64" = .0156" = .396 | #20 = .161" = 4.089 | T = .358" = 9.093 1/32" = .0312" = .795 | #19 = .166" = 4.216 | 23/64" = .3594" = 9.129 #60 = .040" = 1.016 | #18 = .1659" = 4.214 | U = .368" = 9.347 #59 = .041" = 1.041 | 11/64" = .1718" = 4.366 | 3/8" = .375" = 9.525 #58 = .042" = 1.067 | #17 = .173" = 4.394 | V = .377" = 9.576 #57 = .043" = 1.092 | #16 = .177" = 4.496 | W = .386" = 9.804 #56 = .043" = 1.092 | #15 = .180" = 4.572 | 25/64" = .3906" = 9.921 #55 = .0465" = 1.181 | #14 = .182" = 4.623 | X = .397" = 10.084 3/64" = .0468" = 1.191 | #13 = .185" = 4.699 | Y = .404" = 10.262 #55 = .052" = 1.321 | 3/16" = .1875" = 4.763 | 13/32" = .4063" = 10.320 #54 = .055" = 1.397 | #12 = .189" = 4.801 | Z = .413" = 10.49 #53 = .0595" = 1.511 | #11 = .191" = 4.851 | 27/64" = .4219" = 10.716 1/16" = .0625" = 1.588 | #10 = .1935" = 4.915 | 7/16" = .4375" = 11.113 #52 = .0635" = 1.613 | #9 = .196" = 4.978 | 29/64" = .4531" = 11.509 #51 = .067" = 1.701 | #8 = .199" = 5.055 | 15/32" = .4688" = 11.908 #50 = .070" = 1.778 | #7 = .201" = 5.105 | 31/64" = .4844" = 12.304 #49 = .073" = 1.854 | 13/64" = .2031" = 5.159 | 1/2" = .500" = 12.700 #48 = .076" = 1.930 | #6 = .204" = 5.182 | 33/64" = .5156" = 13.096 5/64" = .0781" = 1.984 | #5 = .2055" = 5.22 | 17/32" = .5312" = 13.495 #47 = .0785" = 1.994 | #4 = .209" = 5.309 | 35/64" = .5469" = 13.891 #46 = .081" = 2.06 | #3 = .213" = 5.41 | 9/16" = .5625" = 14.288 #45 = .082" = 2.083 | 7/32" = .2188" = 5.558 | 37/64" = .5781" = 14.684 #44 = .086" = 2.184 | #2 = .221" = 5.613 | 19/32" = .5938" = 15.083 #43 = .089" = 2.26 | #1 = .228" = 5.791 | 39/64" = .6094" = 15.479 #42 = .0935" = 2.375 | A = .234" = 5.943 | 5/8" = .625" = 15.875 3/32" = .0937" = 2.383 | 15/64" = .2344" = 5.954 | 41/64" = .6406" = 16.271 #41 = .096" = 2.438 | B = .238" = 6.045 | 21/32" = .6563" = 16.67 #40 = .098" = 2.489 | C = .242" = 6.147 | 43/64" = .6719" = 17.066 #39 = .0995" = 2.527 | D = .246" = 6.248 | 11/16" = .6875" = 17.463 #38 = .1015" = 2.578 | 1/4" = .250" = 6.35 | 45/64" = .7031" = 17.859 #37 = .104" = 2.642 | E = .250" = 6.35 | 23/32" = .7188" = 18.254 #36 = .1065 = 2.705 | F = .257" = 6.528 | 47/64" = .7344" = 18.654 7/64" = .1094" = 2.779 | G = .261" = 6.629 | 3/4" = .750" = 19.05 #35 = .110" = 2.794 | 17/64" = .2656" = 6.746 | 49/64" = .7656" = 19.446 #34 = .111" = 2.819 | H = .266" = 6.756 | 25/32" = .7813" = 19.845 #33 = .113" = 2.87 | I = .272" = 6.909 | 51/64" = .7969" = 20.241 #32 = .116" = 2.946 | J = .277" = 7.036 | 13/16" = .8125" = 20.638 #31 = .120" = 3.048 | K = .281" = 7.137 | 53/64" = .8282" = 21.034 1/8" = .125" = 3.175 | 9/32" = .2813" = 7.145 | 27/32" = .8438" = 21.433 #30 = .1285" = 3.195 | L = .290" = 7.366 | 55/64" = .8594" = 21.821 #29 = .136" = 3.454 | M = .295" = 7.493 | 7/8" = .875" = 22.225 #28 = .1405" = 3.569 | 19/64" = .2969" = 7.541 | 57/64" = .8906" = 22.621 9/64" = .1406" = 3.571 | N = .302" = 7.671 | 29/32" = .9063" = 23.020 #27 = .144" = 3.658 | 5/16" = .3125" = 7.938 | 59/64" = .9219" = 23.416 #26 = .147" = 3.734 | O = .316" = 8.026 | 15/16" = .9375" = 23.813 #25 = .1495" = 3.797 | P = .323" = 8.204 | 61/64" = .9532" = 24.209 #24 = .152" = 3.861 | 21/64" = .3281" = 8.334 | 31/32" = .9688" = 24.608 #23 = .154" = 3.912 | Q = .332" = 8.433 | 63/64" = .9844" = 25.004 5/32" = .1563" = 3.970 | R = .339" = 8.611 | 1" = 1.000" = 25.400 #22 = .157" = 3.988 | 11/32" = .3438" = 8.733 | #21 = .159" = 4.039 | S = .348" = 8.839 | |
| Thread Size | Actual Outside Diameter of Threads | Closest Drill Bit Size |
| 2-56 | .086" | #44 / 3/32" |
| 3-48 | .099" | #39 / 7/64" |
| 4-40 | .112" | #33 or #34 |
| 5-40 | .125" | 1/8" |
| 6-32 | .138" | 9/64" |
| 8-32 | .164" | 11/64" |
| 10-24 | .190" | 3/16" |
| 10-32 | .190" | 3/16" |
| 12-24 | .216" | 7/32" |
Useful Formulas, Conversion Charts, etc. [Top of Page]
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.
| Gauge | Standard Steel | Galvanized Steel | Aluminum | Gauge | Standard Steel | Galvanized Steel | Aluminum | |
| 3 | 0.2391" | - | 0.2294" | 20 | 0.0359" | 0.0396" | 0.0320" | |
| 4 | 0.2242" | - | 0.2043" | 21 | 0.0329" | 0.0366" | 0.0285" | |
| 5 | 0.2092" | - | 0.1819" | 22 | 0.0299" | 0.0336" | 0.0253" | |
| 6 | 0.1943" | - | 0.1620" | 23 | 0.0269" | 0.0306" | 0.0226" | |
| 7 | 0.1793" | - | 0.1443" | 24 | 0.0239" | 0.0276" | 0.0201" | |
| 8 | 0.1644" | - | 0.1285" | 25 | 0.0209" | 0.0247" | 0.0179" | |
| 9 | 0.1495" | 0.1532" | 0.1144" | 26 | 0.0179" | 0.0217" | 0.0159" | |
| 10 | 0.1345" | 0.1382" | 0.1019" | 27 | 0.0164" | 0.0202" | 0.0142" | |
| 11 | 0.1196" | 0.1233" | 0.0907" | 28 | 0.0149" | 0.0187" | 0.0126" | |
| 12 | 0.1046" | 0.1084" | 0.0808" | 29 | 0.0135" | 0.0172" | 0.0113" | |
| 13 | 0.0897" | 0.0934" | 0.0720" | 30 | 0.0120" | 0.0157" | 0.0100" | |
| 14 | 0.0747" | 0.0785" | 0.0641" | 31 | 0.0105" | 0.0142" | 0.0089" | |
| 15 | 0.0673" | 0.0710" | 0.0571" | 32 | 0.0097" | 0.0134" | 0.0080" | |
| 16 | 0.0598" | 0.0635" | 0.0508" | 33 | 0.0090" | - | 0.0071" | |
| 17 | 0.0538" | 0.0575" | 0.0453" | 34 | 0.0082" | - | 0.0063" | |
| 18 | 0.0478" | 0.0516" | 0.0403" | 35 | 0.0075" | - | 0.0056" | |
| 19 | 0.0418" | 0.0456" | 0.0359" | 36 | 0.0067" | - | - |
Click
Here for Detailed Illustrated Plans on How to Construct a Professional Pull-Back
and Self-Propelled Garden Tractor Pulling Sled (Available
Soon)
To place an order and/or for FREE professional and honest
technical customer service assistance and support,
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; text or when leaving a voice
message, please speak slowly and clearly). Payment
Options. 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.)
E-mail:
pullingtractor@aol.com. A-1 Miller's
shop is open to the public from 9am to 5pm, with an appointment on weekends,
except holidays. Please call, text or email me before coming so I'll be at
my shop waiting for your arrival. When you visit our shop, you will be dealing
directly with the owner for the best customer service.
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
purchase parts, or drop off and/or pick up your carburetor, clutch assembly,
engine parts, entire engine, transmission, transaxle, entire garden tractor,
etc. for repairing and/or rebuilding. "The road to a friend's house (or shop)
is never long." (We're planning to relocate our business to other property
with a bigger and better shop so we can provide many more high quality parts
and professional services.)
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or Website]
To place an order, please call the number below Ê or send an email with your name, complete and correct postal address and phone number and so I can figure the total with shipping cost and USPS Tracking. For payment options for parts ordered or services performed, or to make a donation to my websites, I accept cash (in person), USPS Postal Money Orders, cashier's checks, business checks, MasterCard, VISA, Discover, American Express (please add 2.5% to the total for the credit/debit card processor's surcharge), Western Union Money Transfer or MoneyGram Money Transfers. (If a part for a specific purpose is special ordered, your debit/credit card may be charged for the full amount or as a deposit right after your order is placed; please do not send your debit/credit card information in email!) Or you can pay A-1 Miller's through PayPal. (My PayPal account name is my email address. And be sure to mention in PayPal a description of what the payment is for.) If sending a money order, please include a note in the envelope with your name, complete and correct postal address, phone number and a description of what the payment is for. My mailing address and phone number are below Ê . I'll make a note of your order, and I may have to order some of the parts, which should take a few days to come in, but I will send the parts to you as soon as I have everything in stock after I receive your payment.
IMPORTANT - When sending your part(s) to A-1 Miller's for rebuilding or repair, package everything securely so the item(s) won't get damaged in shipping and please include a note in the box with your name, mailing address, phone number (in case I have any questions) and a description of what you want done. When shipping heavy parts, it's best to put a slightly smaller box inside a larger box, to double the strength and integrity of the package. Because the clumsy "gorillas" or incompetent and uncaring workers that work for certain delivery services mishandle the heavy packages and don't care. And when the work is completed, I'll either call or email you an invoice with the total including shipping & handling.
Payment Options and We Ship to Canada and
Worldwide 
Item(s) in a package or cushioned envelope weighing less than 1 lb. is sent
by US Postal Service Airmail Letter Post for a 4-7 days delivery. Packaged
item(s) weighing over 1 lb. and up to 66 lb. is sent by US Postal Service
Airmail Parcel Post for a 4-10 days delivery. I cannot use the US Postal
Services' Flat Rate Priority Mail envelopes and boxes to ship outside U.S.
territories. Item(s) weighing over 67 lbs. or more is sent by FedEx Ground
or equivalent services. We try to keep our shipping cost to customers within
reason. Therefore, we don't ship our products in a fancy-looking package
with our company name and/or logo on it because most customers will just
toss it in the trash after they remove the contents. And being there is no
USPS tracking number outside the US, all I can do is make sure I write your
address correctly on the customs form and on your package.
My websites are not set up to process orders and accept payments. Therefore, for payment options, I accept cash (in person), USPS Postal Money Orders, cashier's checks, business checks, MasterCard, VISA, Discover, American Express (please add 2.5% to the total amount for the credit/debit card processor's surcharge), Western Union Money Transfer or MoneyGram Money Transfers. If paying with a credit/debit card, please call me at either number below. To make a payment to me through PayPal, please click this link: https://www.paypal.me/PullingTractor. Please use the "Friends and Family" option, or add 3% to the total amount to cover PayPal's processing surcharge. Or to make a payment to me (pullingtractor@aol.com) in the US through the Venmo app, please click this link: venmo.com. Or use Cash App to make a payment to me (pullingtractor@aol.com). And be sure to mention in PayPal, Venmo or Cash App a description of what the payment is for with your full name, postal address, phone number and email address. If sending a money order or cashier's check, please include a note in the envelope with your name, complete mailing address, phone number, email address and a description of what the payment is for. I'll make a note of your order when I have all your information, and I may have to order some of the parts, which should take a few days to come in, but I will send everything on your list to you as soon as I have the parts in stock after I receive your payment.
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