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A huge debt is owed to inventor David Cline for his forward thinking and use of "standard" type parts for the Dynafoils.   What this means to you and me is that parts are still readily available. 
Almost all of the parts on a Dynafoil, except for it's very specific items like struts, hull and gear box, are either automotive, marine, motorcycle, snowmobile, or industrial.
The following list will help you locate almost everything you need:
The correct prop is a Michigan Wheel Propeller, model PJ-19
It is aluminum, pin drive and is 9" in diameter with a 9" pitch  (also knowns as 9x9)  These props are actually Johnson/OMC 25hp pin drive aluminum props.
Order from Michigan Wheel Propellers at:
Michigan Wheel Props run about $65ea.
NOTE:  DO NOT ORDER A PROPCO PROP.  They are too thin and the blades will break off in less than 1 hour of run time.  I've broken 2 of them within days of each other and Propco will not warranty them because they are being used on a watercraft and not a 25hp outboard on an aluminum boat.
A note on propeller installation:  Simply slide the prop onto the shaft so it engages the shear pin.  Then spin the prop nut down finger tight so it is as close to the prop as it can be and still get the stainless cotter pin through it and the shaft.  That's it.  It doesn't need to tighten onto the prop, there are no washers or spacers between the prop nut and the prop.  If you mount the prop in any other way, you will load the rubber bonded hub and it will be spun right out of the prop.  I learned this the hard way.
Propeller Sheer Pin: 
The correct propeller sheer pin is one you make yourself out of a piece of 3/16" #304 Stainless Steel rod.  You can typically buy a 12' length of this material for $4-$8.  You'll need to cut your sheer pins with a hack saw or die-grinder cut-off wheel and they need to be just under 1-1/2" long.  I've got 11' of this stuff left, so email me and I'll make you a couple!
NOTE:  Do not buy a sheer pin from your local Marine/Boat supplier.  They are made for a 25hp application and you'll break them in a matter of minutes, especially if you ride hard. 
Bearings & Seals For Rear Strut:
These are all standard industrial parts available at all bearing and seal supply stores.  Just remove yours and have the supplier measure them for accurate replacements.  Remember to use marine grade greases and oils!  Sources like or Applied Industrial Technologies are excellent sources for high quality bearings and seals.
  • Bearing & Seals at the top of the rear strut. Located just below the bronze "spider" gear (also called a Ball Gear in the Marine world).  This is a tapered needle roller bearing, so you need to order the bearing, and the race. There is a seal on either side of this bearing.
    • Bearing: Timken Part Number: A6062
    • Race: Timken Part Number: TKA6162
    • Seal at top of strut just below the bronze spider gear: TCM Part Number: 11162TB (Replaces #11124 & 471652)
    • Seal at top of strut down inside housing below bearing: TCM Part Number: 061131SC 
  • Bearing & Seals at the bottom of the rear strut. Located just above the large lower foil (wing).  This is a needle roller bearing with a seal on either side.
    • Bearing: J1212
    • Seal at top of bearing: Chicago Rawhide Seal Number: CR 7412
    • Seal at bottom of bearing: TCM Part Number: 071331TZ (Replaces 7028)
Bearings & Seal For Gear Box & Strut:
These are all standard industrial parts available at all bearing and seal supply stores.  Just remove yours and have the supplier measure them for accurate replacements.  Remember to use marine grade greases and oils!  Sources like or Applied Industrial Technologies are excellent sources for high quality bearings and seals. 
  • Bearings for the PTO shaft, 2 required:
    • Bearing Number: "6304" available in Koyo or SKF
  • Seal for PTO shaft, 1 required:
    • Seal Number: C/R (chicago rawhide brand seal) 7536
    • Alternate Number: TCM Part: 075132TB
    • Alternate Number: 471554
  • Seal for the input shaft located next to the water pump, 1required:
    • TCM Seal Number: 08153TC
Clutch Dog:
This is the steel engagement collar that you see inside your PTO gear box in the engine compartment.  You have to remove the four 7/16" headed bolts and then the cover of the PTO gear box in order to see the Clutch Dog.  The Clutch Dog has 2 lugs 180 degrees apart from each other and facing up.  It looks the same on the bottom side where it engages the pinion gear that's located down in the bottom of the PTO gear box.  These lugs get damaged from engaging drive with the engine running at anything other than a low idle.  The Clutch Dog can be removed and flipped upside down in order to have a fresh set of lugs.  But if the lugs on both sides are damaged, you can buy a new one.  They are a common part in Johnson outboards and come in various sizes and styles depending on what they were used in.  It appears that Johnson part #312866 is the version used in the Dynafoil.  They can be found online, and on ebay for $55-$75.
NOTE:  Keep your idle adjusted so it's fairly low and always engage drive by stepping on the metal safety bar quickly.  You want a fast engagement and nice 'clunk' when going into drive.  If you engage drive slowly, you'll hear the clutch dog chattering on top of the pinion gear and this will destroy those 2 lugs.  Once the lugs are damaged, the drive will feel like it's skipping.  Also, before your first ride, take the time to check the engagement rod and bellcrank and the linkage to the safety bar.  You'll probably find everything is out of adjustment, and that there is plenty of mechanical slop which is causing the clutch dog not to be fully engaged eventhough your foot is on the floor.  This is a critical adjustment!
Cooling system:
Water Pump drive belt at front of engine:
From NAPA Auto Parts, part number 7228 will get you a Gates automotive belt that is 5/16"(8mm) wide and 23"(585mm) long.  It fits perfectly.  I've also used a Bando FM 235 fractional horse power belt and it worked great.
Coolant hoses:
Hull to drive shaft mounted water pump: 
  • 3/4" diameter thick wall clear vinyl hose, available at most hardware stores.  Use clear so you can see the water moving through it, so you can tell if the water pump is working.
Drive shaft mounted water pump to exhaust manifold: 
  • 3/4" thick wall clear vinyl hose, available at most hardware stores.  Use clear so you can see the water moving through it, so you can tell if the water pump is working.
Exhaust manifold to upper fitting on the engine mounted water pump: 
  • NAPA Auto Parts part number 7741 (trim slightly to fit). 
Cylinder head to wet muffler: 
  • NAPA Auto Parts part number 7768 (trim slightly to fit)
Water Pump at PTO shaft impeller:
The water pump on the PTO shaft was a special casting made specifically for the Dynafoil. However, in true Dynafoil fashion, it uses standard industrial bearings and seals which are not only readily available, you can get the bearings in stainless steel so they don't rust up and fail prematurely.
  • Water pump shaft seal:  2 required and available from Applied Industrial Technologies (805)928-1683.
    • Dimensions:  1.123" outside diameter x .625"shaft dia. x .313" depth
    • Part Number: TCM Part: 061131SC
    • Alternate Part Number: 480791
  • Water pump shaft bearing: 1 required.  This is a double shielded bearing and is available in Stainless Steel from Applied Industrial Technologies (805)928-1683. 
    • Dimensions:  1-5/8"(1.625") outside diameter x 5/8"(.625") shaft dia. x 1/2"(.50") depth
    • Stainless Steel version Part Number: SS 1628 2Z
  • Water pump impeller:  is a standard Johnson/OMC outboard impeller. It is OMC part number: 378891 It is made in the aftermarket by Marine parts supplier, "Sierra" and is part number 18-3006.
    • Purchase them from the following supplier who went out of his way to measure these and make sure they were the correct impeller:
    • Vintage Outboard and Marine Supply
      a division of Brooke Enterprises, L.L.C.
      Spokane, WA
      Phone (509) 747-9960
Throttle & Grips:
Twist Throttle:
This is a standard single cable motorcycle throttle available at all motorcycle/motocross repair shops and parts sources for about $22.
Throttle Cable:
Most motorcycle shops can custom make throttle cables.  Modern cables are stainless steel and run inside a teflon sleeve inside the main cable housing.  Definately worth having one built, especially if yours is getting stiff from rust inside and not being used.
Handle Bar Grips:
These are standard motorcycle handle bar grips.  Availlable at all motorcycle/motocross repair shops and parts sources for about $9.  Make sure to buy the pair that have one grip larger to fit over the twist throttle.
Fuel system:
Fuel Gauge:
Standard industrial 1/4 turn fuel tank cap with built in gauge.  These are available in the correct length from long-time manufacturer, Kelch:  
They run about $25ea. and take a couple weeks to make.
Fuel Filler Assembly On Hull:
Technically called a "Deck Fill."  This is a standard marine/boat  assembly made by "Perko."  Still available at any boat/marine supply store.  Also available online on or   The original ones were black, and Perko still makes that version.  $10-$13 online plus shipping, or about $20 at your local marine/boat supply store.  You want the version with the 1-1/2" neck into the hull.
Fuel Filler Hose:
This is a standard automotive fuel tank filler neck hose 1-1/2" diameter.  Available at NAPA or similar quality auto parts stores.  Marine grade fuel hose is also available and may be mandated for your boating use in your area.  Buy it cut to length.
Fuel Hose & Fuel Tank Vent Hose:
I use the clear hose for motocross motorcycles because it allows me to see the fuel flow.  Very handy when diagnosing running problems.  Available at most all motorcycle, ATV and watercraft parts sources.
NOTE:  Always replace your fuel tank vent hose AND blow through each of the vent fittings (there's one back at the stern and one inside the fuel filler neck housing next to the gas cap) because they are generally plugged solid from years of sitting.
Bilge Pump:
Standard marine bilge pump.  Available in various output ranges from all boat/marine parts stores. 
NOTE:  The bilge pump runs continuously when the engine is running
Voltage Rectifier For Bilge Pump:
This is actually located in the lid of the box that houses the ignition coil and CDI unit.  The full wave rectifier simply converts the AC voltage coming out of the engine's lighting magneto into 12v DC to run the bilge pump.  The rectifier is built out of standard electrical components available at most electronics stores. 
Ignition Coil & CDI Unit:
Standard snowmobile ignition components used in both Rupp and Chaparral snowmobiles, to name a few.
  • CDI Ignition Unit No. CU11 made by Kokusan Denki Co. in Japan
Engine Gasket Kits:
Standard snowmobile components used in both Rupp and Chaparral snowmobiles.  Available online from
2 Stroke oil:
I use full synthetic 2 stroke oil (Torco Synthetic) mixed at 40:1 and have had excellent results.  Very little smoke and I've got a year out of my spark plugs and they still look great.  The original recommended ratio was 20:1 with conventional 2 stroke oil.
Gear Oil & Bearing Grease:
I use synthetc 85/90w Marine Gear Oil.  Remember to use Marine rated oils and grease because they don't create acid when water gets mixed in with them...and it will.  This acid causes bearings and gears to rust fast and will ruin them. 
Lovejoy Coupler (the rubber coupler at the engine):
These rubber ring "Saga" style couplers are still made by the company in Illinios.  The "Saga S-11" Coupler runs $60-$75ea so it pays to shop around a bit.  Look them up on the net  or buy them from your local industrial supplier.  Their cool pdf catalogue is at:  Just scroll all the way down until you get to the Saga Coupler catagory.
I got mine from a nation-wide industrial supply chain called "Applied Industrial Technologies."  They have great service and excellent parts quality.
Motor Mounts:
These are the same as Kawasaki Jetski 440/550 mounts from the older models.  They are available in standard OEM rubber, or in the super strong "Monkey Grip" version for about $144.  See your favorite personal watercraft parts vendor for these, or contact Dan Fitzgerald at "Jet World" in Burbank, CA at (818)559-9610.
(I ordered 4 from Dan and got them in 3 days via UPS.  They are definately indestructable.)
You can also get them from Parker Yamaha in Parker, AZ. or call them at (928)669-2385.  $30.80ea
Duckbill Drain:
Standard marine duckbill.  These are used for the bilge pump's opening in the transom as well as for the footwell drain openings.  Order them from "Blowsion" in Sherwood, OR at (503)625-3616
  • Part number: KASRAS101 for $21.95.  Great bunch of guys and they're willing to ship regular mail for about $1.50 instead of $8 for UPS.
(I ordered one from Blowsion and got it in 3 days via US mail.  By the way, these guys are closet Dynafoil lovers!)

You can also get them from Parker Yamaha in Parker, AZ.  or call them at (928)669-2385. 

  • Their part number is Atlantis A-2019 and they are $15.95.
Note:  I suggest not using them on the footwell drains so the drains will drain faster.  But, I think they are important on the bilge because it will keep water from coming back into the bilge when you're getting crazy, or when you're sitting still and waves hit the stern.
Front Foil:
Front Foil Bronze Pivot Bushings:
  • 4 Required: Standard oil impregnated bronze bushings with the thin flange. 1/4" dia inside bore, 3/8" outside diameter and 1/4" tall (long). 
    • Part No. 6338K411  You'll need 4 and they are 49 cents each from McMaster-Carr in Los Angeles, CA. (562)692-5911

NOTE: These are the bronze pivot bushings for the actuation of the water sensing flaps as well as the foils on the front strut.

Front Foil Nylon Bushings:
Standard thin wall, thin flange white nylon bushings made by Thompson and sold through places like "Applied Industrial Technologies." 
  • 23 required, and they are .28 cents each. 
  • Part Number: 5L5F.  Applied Industrial Technologies has warehouses and distributors all over the USA.  Here's the number for the AIT distributor I use:  (805)928-1863.

NOTE: These are the nylon bushings that the water sensing flaps and the foils ride against.  They are positioned just behind the flange of the flaps and the flange of the foils and are installed in the front strut so every other bushing faces the opposite direction.  It is these nylon flanges that the flaps and foils glide against as they rotate up and down.

Front Foil Stainless Pivot Pins:
These are 18-8 or 316 Stainless dowels 5/16"(.3125") in diameter and approximately 7/8" long.  These are turned down on a lathe so each end is 1/4" in diameter to fit into the oil impregnated bronze bushings listed above.  These also come in oversize diameter of +.0001" which is nice incase the metal levers inside the front strut are wallowed out where these pins have been running. 
  • 2 required. Part No. 90145A580 gets you the standard dimension version in 7/8" length.  
    • Order from McMaster-Carr in Los Angeles, CA. (562)692-5911
Front Strut Aircraft Hitch Pins:
Standard Aircraft type "L Handle Quick Release Pin" (5/16" hitch pins).  
  • 2 required, Part No. 903022A211
    • Order from McMaster-Carr in Los Angeles, CA. (562)692-5911 

NOTE:  I paid $25 locally, but if you buy from McMaster-Carr directly, they should be cheaper.  They're made by "Jergens" in Cleveland, OH.