Sleeve Valve Radial

Engineering Description 

         The 14 cylinder - Sleeve Valve Radial - is a double row, 4 cycle, direct drive, naturally aspirated engine with a dry sump oil system and electronic ignition.

          A Sleeve Valve engine is characterized by a sleeve between the piston and cylinder. Various ports allow the Fuel \ Air mixture and exhaust to flow into and out of the combustion chamber. There are no overhead poppet valves, cams, pushrods or rocker arms.   

          Each sleeve is actuated by its own short stroke crank, using a ball and socket arrangement. The sleeves operate at half crankshaft speed and are operated by a series of 29 spur gears.    

         The conservative design has a 7.2 to 1 compression ratio and is  designed for manufacture with a minimum of specialized equipment. Speed is 400 rpm idle and 2000 rpm at full power. The engine is equipped with an  oil system that supplies pressure lubrication to both main crank throws. Three (3 ) additional oil jets supply oil to the sleeve drive gears as well as the front and rear sleeve ball sockets. The ignition is operated from a distributor for each row. The high tension for each row is supplied by a Capacitive Discharge Ignition ( CDI ) system triggered by a Hall Effect sensor. 


         The crankcase of the engine is made of seven ( 7 ) sections. The bearing housing, the gear housing, the front, middle and rear crankcase sections and the induction housing are all are machined from 6061 aluminum billet. The last section is the distributor drive, made from a 356-T6 aluminum casting that has various bosses.   

         The bearing housing is equipped with a large ball bearing that supports the front shaft thrust loads. The housing is piloted to the gear housing and secured by fourteen ( 14 ) bolts. The gear housing encloses the twenty nine ( 29 ) spur gears and is equipped with fourteen ( 14 ) bronze bushings to support the ends of the fourteen ( 14 ) individual sleeve crankshafts. The gear housing is piloted to the front crankcase and secured by fourteen ( 14 ) bolts. 

        All three of the crankcases are piloted together, secured by seven ( 7 ) bolts and are split at the cylinder centerline. The front crankcase is equipped with a ball bearing that supports the front journal of the main crankshaft. There are seven ( 7 ) additional ball bearings located on the periphery of the front crankcase. These bearings support the front row sleeve drive shafts. In addition, there are seven ( 7 )  clearance holes to allow the rear sleeve crankshafts to pass through to the rear row.  

          The middle crankcase is equipped with a gear type positive displacement oil pressure pump and a separate gear mesh scavenge oil pump. These pumps are driven from a gear mounted on the middle crankshaft journal. The middle crankshaft is supported by a bronze bushing. This arrangement provides an oil flow passage from the pressure pump to oil galleries in the crankshaft. There are seven ( 7 ) additional ball bearings located on the periphery of the middle crankcase to support the rear row sleeve crank drive shafts.  

        The rear crankcase is equipped with a ball bearing that supports the rear of the main crankshaft. The rear crankcase is also piloted to the Induction housing and secured by fourteen (14 ) bolts that extend from the rear crankcase through the induction housing. Eight ( 8 ) of these bolts are longer, for securing the engine to the engine mount.   

        The induction housing includes a provision for a large diameter  impeller, driven directly by the rear crankshaft. The housing directs the fuel \ air mixture through the impeller blades into a large annulus that leads to the fourteen ( 14 ) intake pipes which, in turn, lead to each individual cylinder.    

         The induction housing includes the mounting for the rear casting secured by eight ( 8 ) bolts. The rear casing has two ( 2 ) bosses used to mount the distributor assemblies. An additional boss provides a mounting surface for the carburetor.    


        The cylinders are machined from 6061 aluminum billet and are deeply finned for cooling, the cylinders are hard black anodized for surface protection. The bottom of the cylinder is provided with a mounting flange that secures the cylinder to the crankcase mounting pad. The cylinders are  secured by sixteen ( 16 ) bolts. The middle of the cylinder has a provision for two ( 2 ) forward facing exhaust ports. Also, in the middle of the cylinder, facing toward the rear, are three ( 3 ) intake ports that are covered by a semi-circular intake cuff, secured by sixteen ( 16 ) screws. The five ( 5 ) port shapes are machined into the cylinder. The top of the cylinder is secured to the cylinder head by six ( 6 ) bolts. 

        The cylinder heads are of the junk head type, extending deep into the cylinders, They are machined from a single piece of 6061 aluminum billet. The heads are equipped with two ( 2 ) compression rings. The top of the heads are provided with integral cooling fins and also are equipped with two ( 2 ) vent holes that  prevent hydraulic locking of the sleeve. The head is tapped for a single spark plug. A brass gasket provides sealing between the head and cylinder. 


        The sleeves are made from 1145 steel billet. The bottom of the sleeve is provided with a mounting pocket that locates the one-piece ball socket firmly to the sleeve. The ball socket is secured by two ( 2 ) high strength Allen head screws.  Four ( 4 ) ports are milled into the sleeve. The outer diameter of the sleeve is honed to operate inside the cylinder. The inner diameter is honed for the operation of the piston. 


        The crankshaft is made from nine ( 9 ) pieces. The crank throws are made from 4140 steel clamped to the crank cheeks with high strength Allen head bolts. The shafts are secured to the crank cheeks using using a square shape. This square hole arrangement transmits the torque and provides a secure connection between the shafts and crank cheek. The joint is secured with a taper pin. No welding, that might warp the parts, is required.    

        The crankshaft is equipped with oil galleries that direct the oil from the center main journal to the two ( 2 ) master rod journals, then to three ( 3 ) oil jets that provide lubrication for the sleeve drive gears, the sleeve ball socket joints and the sleeve crank ball bearings.

         The front shaft is equipped with a hole that provides a crankcase breather. The front shaft also has the integral gear that operates all of the sleeve drive gearing.

          The rear shaft is equipped with a drive for the impeller and supports a helical gear for the distributor drives.   

      Connecting Rods 

        The master rod is a single piece, machined from 1145 steel billet. The lower end is equipped with a plain bronze bushing. The six ( 6 ) articulated or link rods, are of the same construction. The master rod is not compensated.  


        The pistons are machined from 2024 aluminum billet. Each piston is fitted with two cast iron compression rings above the piston pin. The piston pin is of the floating type, with aluminum plugs at each end to prevent scoring of the sleeve wall. The bottom of the pistons are equipped with an oil control ring and a series of holes to direct the oil back to the crankcase.  

       Lubrication System 

        Oil is supplied from an external supply tank through transfer tubes to the positive displacement gear pump.

        The pump is mounted in the middle crankcase and is driven by a series of spur gears. The oil is directed to the crankshaft oil galleries where it travels to the crank throws under the master rods. The oil also flows to three oil jets that lubricate the spur gears and sleeve cranks. The oil returns by various holes in the crankcases to a sump located behind cylinder #8. Oil is then directed to the oil scavenge pump and return to the supply tank.  

       Intake System 

       The fuel \ air mixture exits the carburetor and is turned radially outward and passes through the crankshaft driven impeller. The fins of the impeller ensure complete atomization. The mixture is then conveyed to one of the fourteen ( 14 ) intake pipes leading to the intake cuff mounted on each cylinder.    

         Ignition System  

         The two ( 2 ) distributors, one for each row, are driven by a set of helical gears giving a 2:1 speed reduction. Each distributor rotor is equipped with seven ( 7 ) magnets that  trigger the Hall Effect sensor. The ignition system consists of two ( 2 ) CDI units, one for each row, that provide the spark. The ignition voltage is sent to the top of the distributor and then to the correct cylinder.    

         The distributor cap is made from black Delrin. The cap is made with a single center contact and seven ( 7 ) individual contacts at the periphery. Each contact has a screw thread for positively securing the spark plug wire eyelet to the contact.              

        Additional Features  

        The engine drawings also include an engine mounting stand and an oil and fuel supply tank for bench running.



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