Atomic Four Specifications

Universal Atomic Four: UJ, UJR, UJVD
Universal Atomic Four Stevedore: UJS, UJSR, UJSVD

Specifications & Dimensions	Models	5101 / UJ - base configuration Atomic Four 5111 / UJS - Stevedore configuration for Canadian market, power limited to 15 hp with intake manifold restriction) 5102 / UJR - reduction gearbox mounted on transmission, 2.04 ratio standard 5112 / UJSR - Stevedore configuration with reduction gearbox mounted on transmission, 2.04 ratio standard 5103 / UJVD - 20° angle Walter V drive gearbox mounted on transmission, 4 gear ratio options including 1:1 5113 / UJSVD - Stevedore configuration with 20° angle Walter V drive gearbox mounted on transmission, 4 gear ratio options including 1:1
	Type	Vertical, in line, 4 cycle, L (flat) head
	Serial Number Locations	Pre 1969: stamped on right, forward side of block above starter motor Post 1968: stamped on block above flywheel housing, and on an id tag glued to top of manifold Post 1977: stamped on block above flywheel housing, on an id tag glued to top of manifold, and on an id tag glued to front of the flywheel housing cover
	Cylinders	4
	Bore	2.562 in
	Stroke	3.125 in
	Engine displacement (swept volume)	64.44 cu in / 1055.98 cc
	Compression Ratio	6.3:1
	Cylinder Block	Cast en-block with marine chrome nickel alloy iron crankcase & full length water jackets
	Cylinder Head	Marine chrome nickel iron detachable head
	Crankshaft	2 main bearing, high carbon steel, fully counterweighted, statically and dynamically balanced, uses insert bearings
	Connecting Rods	Drop forged, high carbon steel, floating piston pin, insert bearings
	Pistons	Cast aluminum, flat-top, 3 ring - 2 compression rings and 1 oil control ring, floating piston pin retained by steel circlips, pin offset .005", expansion slot on non-thrust skirt
	Oil pan	Marine chrome nickel iron, one piece, partially baffled marine type, integral engine mounts
	Manifold	Water jacketed exhaust and intake manifold in one casting. Separate exhaust flange tapped 1 1/4 in NPT bolts to manifold with two 3/8" NC cap screws or studs at exhaust opening at rear of manifold. V drive models use same manifold with cap over rear opening and front opening machined for exhaust flange so that engine can be mounted facing backwards, as required for use of V drive.
	Exhaust pipe	1 1/4 in NPT (pipe thread) galvanized thick wall pipe
	Lubrication	Full pressure to mains, connecting rod big ends, idler gear stud, camshaft bearings, transmission sun & planet gear assembly Marine type fine brass mesh oil pump pickup screen surrounding pickup to retain oil in rough seas and prevent oil pump ingesting air, exterior oil pressure adjustment
	Water jacket cover	Removeable block water jacket plate (standard is carbon steel, stainless steel plates available from after-market suppliers)
	Cooling system	Constant flow, 2 stage thermostat, rubber impellor water pump (later models)
	Thermostat upper plate height	OEM Holley 3 spring: closed (cold) .325 in / open (hot) .625 in replacement Westerbeke single spring: closed (cold) .2 in / open (hot) .8 in
	Thermostat housing bypass boss depth	.4 in - .5 in
	Mechanical fuel pump pushrod size	1.550 in long x .375 in diameter
	Marine gear (transmission)	Paragon: combined engine / marine gear lubrication system with marine gear running in engine oil, sun and planet gear type, forward uses multiple plate clutch pack with over-centre pressure and lock, reverse uses clutch band on sun gear housing, the carrier gear assembly is pressure lubricated via a port on the crankshaft rear main bearing, the rear thrust bearing at the drive flange is splash lubricated via a bearing shield which meters the oil to and from the bearing / rear seal.
	Reduction Gear (optional)	Single step, internal helical and pinion type, 2.04:1 ratio
	Carburetor	Updraft Zenith marine non-drip type carburetor, upturned air horn with flame arrester screen: 1949 - 1968 Zenith Bendix type 61, cast-iron (adjustable main jet) 1969 - 1984 Zenith Bendix type 68, aluminum (fixed main jet)
	Electrical Charging System	Post 1967 12 volt DC, 35 amp Motorola marine alternator, transistorized alternator-mounted voltage regulator, 12 volt DC solenoid equipped starter (optional 50 amp Motorola marine alternator was available at extra cost)
	Propeller rotation	Right hand (clockwise facing the rear of the propeller)
	Propeller shaft / coupling diameter	Direct Drive: ¾ in, 7/8 in, 1 in Reduction Drive: 1 in, 1 1/8 in V Drive: 7/8 in, 1 in
	Propeller Size Note: propeller fitted must allow the engine to reach at least 1,800 rpm during hull speed / full throttle testing	2 Blade Direct drive: 11 x 7, 12 x 6 (most common size), 12 x 7, 13 x 5 2:1 Reduction Drive: 12 x 11, 12 x 12, 13 x 10, 13 x 12, 15 x 8, 15 x 10 3 Blade (recommended for areas with severe currents, winds, tides) Direct drive: 10 x 6, 10 x 7 2:1 Reduction Drive: 12 x 9, 12 x 10, 13 x 8, 13 x 9
	Crankshaft rotation	Clockwise (right hand) viewed from rear of engine output shaft
	Reduction gear ratio options	2.04:1, 3.01:1
	V drive ratio options	1.00:1, 1.29:1, 1.67:1, 2.0:1
	Torque / RPM / HP
	Fuel	Original specification was "standard 92 - 94 octane gasoline", later revised to "regular 90 - 94 octane" (when the specifications were written all gasoline contained lead, which was used to raise the octane rating and extend valve seat life). Modern "Regular" 87 or 89 octane non-leaded gasoline is OK as long as the compression is below 120 psi and the ignition timing is set by adjusting distributor at full cruise speed to give maximum tachometer rpm. Octane booster & lead additive is not recommended or necessary.
	Maximum operating angle	15°
	Length overall	UJ: 26 ¾ in, UJR: 31 15/16 in, UJVD: 35 13/16 in
	Height above crankshaft centreline	13.125 in
	Maximum width	18.250 in
	Offset – crankshaft to propeller shaft	UJ: 0 in UJR: 1.042 in UJVD: na
	Base depth below centreline	6 in
	Weight	UJ: 310 lb UJR: 330 lb UJVD: 335 lb
	Firing order (#1 cylinder: flywheel end)	1 2 4 3
	Valve timing	Inlet valve opens: 5 BTDC Inlet valve closes: 50 ABDC Exhaust valve opens: 45 BBDC Exhaust valve closes: 10 ATDC
	Valve guide dimensions	1.5 in long x .5 in diameter
	Valve length	3.685 in
	Intake valve head diameter	1.500 in
	Exhaust valve head diameter	1.030 in
	Valve spring diameter	1949 – 1967: .785 in 1966 – 1967: .800 in 1968 – 1984: .810 in
	Valve spring free length	1949 – 1967: 1.825 in (coil bound at .760 in) 1966 – 1967: 1.925 in (coil bound at .800 in) 1968 – 1984: 2.075 in (coil bound at .810 in)
	Compression	90 psi – 125 psi, optimum 100 psi
	Alternator drive ratio (through PTO gear & V belt pulley)	1.75:1 (1 turn of engine crankshaft = 1 ¾ turn alternator)
	Flywheel ring gear & housing dimensions	1949 – 1967 (Prestolite starter): ring gear OD / flywheel housing ID 11 in 1968 – 1984 (Delco starter): ring gear OD / flywheel housing ID 11.5 in
	Fuel consumption	Approximately 4 litres/hour (1 US gal/hour) @ 2,000 rpm under load depending on boat size & winds/currents
	Auxiliary primary fuel filter recommendation	Filter mesh size & type rating: 10 micron with water separator section & metal bowl (ie Racor 320R-RAC-02) Minimum Flow Rating: 15 litre / hour
	Mechanical fuel pump	AC Delco mechanical rubber diaphragm type, maximum pressure 3.0 psi Auxiliary sediment bowl with internal mesh filter
	Electric fuel pump	Facet 574A, 12 volts, maximum pressure 4.0 psi Internal mesh filter accessible by removing cam lock bottom cap In-line fuse 10 amp Should be fitted with oil pressure safety switch (Hobbs 76576 - 10 n.o.) to stop pump if engine stalls or ignition switch left in "on" position
	Pipe / Hose Sizes	Exhaust flange: 1 1/4 in NPT - 1 1/2 in or 1 /5/8 in hose Water pump inlet: 3/8 in NPT - 1/2 in or 5/8in hose Water pump outlet: 3/8 in NPT - 1/2 in hose Fuel pump connection: 1/8 in NPT - 5/16 in OD copper pipe, double flared or 1/4 in ID hose (alcohol compatible)
Design Changes	Engine Specification Updates	circa 1949: Serial #? Zenith series 61-M2AE7 cast iron carburetor with adjustable main jet Dole thermostat Auto-lite ignition Fairbanks Morse magneto (optional) Auto-lite 6 volt starter Auto-lite 6 volt generator Prestolite distributor (1Gw60032E1X) bronze gear water pump old style heat exchanger kit (optional) 5 unit control panel with mechanical tachometer, mechanical oil pressure gauge, mechanical water temperature gauge circa 1962: Serial #? Jabsco rubber impellor water pump (available as a replacement) Prestolite 12 volt starter Leece Neville 12 volt alternator (optional) circa 1963: Serial #? Prestolite 12 volt generator Auto-lite 15 amp 12 volt generator (optional) Delco Remy 24 amp 12 volt generator (optional) Prestolite 35 amp 12 volt alternator (optional) Prestolite 40 amp 12 volt alternator (optional) circa 1964: Serial #? Ongaro - Teleflex electric control panel with electric tachometer (optional), electric oil pressure gauge, electric water temperature gauge circa 1965: Serial #? "old" Sherwood (7 end cover screws) rubber impellor water pump circa 1967: Serial #79476 new style cylinder head with thermost housing Holley thermostat new style Sendure heat exchanger kit (optional) Medallion 6 unit control panel with electric tachometer (optional), electric oil pressure gauge, electric water temperature gauge circa 1967: Serial #170509 Zenith series 68-7 alumininum alloy carburetor with fixed main jet Delco Remy distributor (#1112446 - 2G11/6C16/3HI8) Delco Remy 070FLX 12 volt coil Delco Remy 1107679starter and new ring gear to fit larger flywheel housing to fit new ring gear Motorola 35 amp 12 volt alternator Motorola 51 amp 12 volt alternator (optional) Oberdorfer model 202M3 rubber impellor water pump (fitted to most engines) circa 1967: Serial #171514 external valve chamber oil line no longer fitted circa 1968: Serial #174340 Oberdorfer model 202M3 water pump standard circa 1969: Serial #174802 new style valves (stamped "Eaton" or "Etn") circa 1969: Serial #175503 new transmission housing, oil fill moved to front circa 1970: Serial #176500 valve guide inner diameter revised to .3145 - .3150 in (new valve guide/valve stem clearance specification of .003 - .004 in to prevent valves sticking in guides) circa 1972: Serial #178801 Paragon marine gear updated with new outer plate combined with pressure plate, and new wider metric gear carrier ball bearing circa 1975: Serial #192787 new style deep flywheel housing and flat sheet metal cover circa 197?: Serial #? new style electric instrument panel (electric tachometer optional) circa 1979: Serial #202987 mechanical fuel pump replaced with Facet electric fuel pump and low oil pressure shut-off switch circa 1980: Serial #20? production stopped (sales continued to 1984)

Wear Limit Sizes/Clearances	Bore	Std size: 2.562 in – 2.563 in .010 in oversize: 2.572 in – 2.573 in .020 in oversize: 2.582 in – 2.583 in
	Piston skirt clearance	.001 in - .002 in (.0015 in feeler blade to 5 lb pull)
	Piston ring gap	.007 in - .015 in Note: ensure replacement Hastings or Ertel oil ring bottom spring end gaps are over oil drain slot in bottom of oil ring land replacement Hastings piston rings are configured as follows: top groove: bevel on inside of ring - UP second groove: lip on outside of ring - DOWN oil ring inner spring: gap over piston vertical expansion slot / ring land slot oil ring: EITHER SIDE UP Note: Install rings with gaps staggered 120 degrees around piston. Do not locate any gaps on thrust side
	Piston ring side clearance	Top (compression): .0015 in - .003 in Middle: .001 in - .0025 in Bottom (oil): .001 in - .0025 in
	Piston pin diameter	.6880 in
	Piston pin rod bushing ID	.6885 in - .6900 in
	Piston pin clearance in rod bushing (slip fit)	.0005 in - .001 in
	Piston pin clearance in piston (push fit)	.0001 in - .0005 in
	Oil pump drive end play	.001 in - .003 in
	Oil pump gear backlash	.003 in - .005 in
	Camshaft gear backlash	.002 in - .004 in
	Idler gear backlash	.002 in - .004 in
	Accessory gear backlash	.002 in - .004 in
	Connecting rod big end side play on crankshaft journal	.004 in - .008 in
	Crankshaft end play (at front main bearing)	.002 in - .003 in
	Valve seat angle	45°
	Valve seat width	1/32 in
	Valve stem diameter	.3115 in - .312 in
	Valve stem / guide clearance	cast iron guides: .003 in - .004 in (OEM guides are cast iron) bronze guides in fresh water cooled engines with 180 thermostat: .0035 - .0045 in
	Valve guide internal diameter	.3145 in - .3165 in (see valve stem/guide clearance above)
	Valve spring installed length - no cam lobe lift (intake & exhaust)	1.19 in
	Valve spring length - cam lobe full lift (intake & exhaust)	.94 in
	Maximum cam lobe lift	.239 in
	Valve face angle	45°
	Crankshaft main bearing journal	Std: 1.9880 in, +.0005 in / -.0000 in .010 in undersize: 1.9780, + .0005 in / - .0000 in .020 in undersize: 1.9680, + .0005 in / - .0000 in .030 in undersize: 1.9580, + .0005 in / - .0000 in
	Crankshaft rod bearing journal	Std: 1.5625 in, +.0000 in / .-.0005 in .010 in undersize: 1.5525 in, + .0000 in / - .0005 in .020 in undersize: 1.5425 in, + .0000 in / - .0005 in .030 in undersize: 1.5325 in, + .0000 in / - .0005 in
	Crankshaft marine gear sun & planet carrier bearing journal	1.869 in, +.0005 in / .-.0000 in
	Main bearing clearance	.001 in - .0025 in
	Rod bearing clearance	.001 in - .0025 in
	Rod big end diameter	1.665 in
	Rod side play on crankshaft journal	.004 in - .008 in
	Rod installation	Cylinder no stamped on rod big end towards camshaft, #1 rod at front (flywheel end) on #1 piston, #2 rod second from front on #2 piston, etc
	Camshaft bearing journal	1.3745 in, +.0005 in / -.0000 in
	Camshaft bearing clearance	.0015 in - .0025 in (line ream after installation)
	Piston installation	Arrow on crown pointing to rear (towards marine gear), vertical expansion slot on skirt facing away from camshaft, #1 piston at front (flywheel end), #2 piston second from front, etc
	Piston skirt diameter (bottom of skirt near expansion slot at right angles to pin) Note: pistons are not round when at room temperature because they are cam ground oval so they expand to round when at engine running temperature	Std: 2.560 in .010 in oversize: 2.570 in .020 in oversize: 2.580 in .030 in oversize: 2.590 in
	Front main bearing width:	1.620 in
	Idler gear shaft diameter	.8766 in, +.0000 in / -.0002 in
	Idler gear bushing id	.8772 in - .8777 in
	Camshaft bushing inner diameter	1.376 in – 1.377 in
	Oil pump drive end play	.001 in - .003 in
	Distance from top of cylinder head spark plug thread to cylinder block deck	.980 in - 1.175 in
	Distance from bottom of spark plug thread to cylinder head surface	.480 in - .625 in, average approximately .525 in
	Cylinder head combustion chamber volume with piston at TDC (including spark plug hole)	40 cc - 51 cc, average approximately 50 cc
	Cylinder swept volume + combustion chamber volume with piston at BDC (including spark plug hole)	313.5, average approximately 314 cc
	Maximum cylinder bore ovality	.002 in
	Maximum cylinder bore taper	.008 in
	Maximum cylinder head warp	.006 in
	Valve spring compressed length (full lift of camshaft lobe)	?? in
	Valve spring installed height (with valve clearance)	?? in
	Coil primary resistance	Internal ballast type: 3 - 4 ohm (standard coil) (Note: External ballast type (.5 - 1 ohm) is not necessary or recommended. If fitted an external ballast resistor (2 - 3 ohm) must also be installed in series.)
	Starter solenoid current draw Starter winding currrent draw	approximately 20 amps approximately 150 amps
	Valve spring pressure	??
	Intake manifold vacuum	Idle: 16 in Hg 2,000 rpm under load: 14 in Hg
	Exhaust system back pressure (measured after water injection point)	3 psi / 3 in Hg maximum at full load
	Crankcase sump flow (indicating piston ring and valve guide combustion blow-by)	New engine: approximately .25 cfm/+.5" H2O/?psi at full speed / load Worn engine: approximately .50 cfm/+?H2O/?psi at full speed / load
	Distributor rotor position @ TDC#1 (compression stroke)	#1 terminal at 09:00 viewed from front of engine (pointing to extrusion on distributor plate which fits into slot in cap and is also at 09:00)

Adjustments	Ignition timing	Static: No advance = 0° BTDC / Full advance = 17° BTDC Dynamic: <700 rpm = 0° BTDC / >1,800 rpm = 17° BTDC
	Valve tappet clearance	Intake: .008 in hot, .010 in cold Exhaust: .010 in hot, .012 in cold
	Distributor dwell	Prestolite: 38° Delco: 31° - 34°
	Distributor points gap	Prestolite: .018 in - .020 in Delco: .025 in magneto: .014 in - .018 in
	Spark plug gap	.035 in
	Alternator belt tension	3/8 in depression between centres, pressing firmly with one finger
	Oil pressure relief valve	35 psi at 2,000 rpm (or top cruising speed) hot
	Paragon marine gear forward clutch pack	approximately 30 - 50 ft lb torque on shift shaft to force 3 pressure plate arms over bulge in throw-out bearing
	Paragon marine gear rear band	with gear lever in neutral tighten reverse band adjusting nut (holes in flats so a nail or pick can be used as an adjusting tool) until output shaft turns stiffly, then back off 1 - 2 rotations until shaft turns freely

Machining Specs	Cylinder head & manifold grinding finish	#125 RMS / #112 RA
	Cylinder bore honing finish	Hone finish, 60° crosshatch pattern (Std size bore 2.562 in - 2.563 in)
	Cylinder block deck & manifold finish	#90 RMS / #80 RA

Lubricants	Lubricating oil	Depending on installation angle of engine: 4 litres – 6 litres at temperatures over 10°C / 50°F use SAE 10-30, 10-40, 15-40, SJ or CH-4 rating, to full mark on dip stick (different dip sticks for UJ, UJR, UJVD)
	V Drive Oil	.5 litre of SAE 80W90 hypoid oil (SAE 30 motor oil is also acceptable)
	Water pump grease	Waterproof grease (white lithium, boat trailer wheel bearing grease, etc)

Fastener Torque Note: Lubricate threads and base of bolt head / nut with oil	Cylinder head stud nuts	35 ft lb, 3 stages: 10 ft lb / 25 ft lb / 35 ft lb, use shop manual torquing diagram or torque from centre of head out to ends. Retorque hot to 35 ft lb after 1 hour of running. Be careful not to exceed 35 ft lb. On older engines stud pull is a common problem. If a stud pulls the threads out of the block remove the head and install a 3/8" NC thread repair insert. Note: install cylinder and manifold studs into block with gasket cement or Loctite "red", and coat sides of studs with Never-Seize to prevent studs from seizing to head or manifold
	Connecting rod bolt nuts	25 ft lb
	Flywheel stud nuts	35 ft lb
	Main bearing stud nuts	60 ft lb
	Manifold stud nuts	30 ft lb
	Spark plugs	30 ft lb (apply Never-Seize to threads)
	Valve cover cap screws	20 in / lb (with cork gasket)
	Flywheel cover cap screws	85 in / lb
	Idler Gear stud nut	35 ft lb (use red Loctite)
	Oil pump cover screw	12 ft lb (use blue Loctite)
	Oil pan & block 5/16" cap screws	18 ft lb
	Transmission output shaft flange nut	60 ft lb (use tab lock washer)
	Crankshaft channeled gear retaining bolt	25 ft lb (use blue Loctite)

Service Parts	Spark plugs	Specified plug: Champion #871 (old number RJ8C) Recommended plug (slightly hotter, helps stop plug sooting): Champion #592 (old number RJ12C) Other plugs used (nominal Champion RJ8C equivalents): NGK BR6S Bosch W7EC, W7E, W9EC AC R43, R44, R45 Autolite 304 Motocraft A3C, A3CU, A3X, A5X, A5CU Denso W20S, W20SR-U, W20S-U
	Contact Breaker (points)	Prestrolite Distributor: Echlin CS-709 Delco Distributor: Delco D108P Echlin CS788P Niehoff DR6 HV
	Capacitor (Condenser)	Prestolite Distributor: Echlin AL38 Delco Distributor: Delco D203 Echlin RR-176 Niehoff DR-22 Borg Warner G126
	Rotor	Prestolite Distributor: Echlin AL58 Delco Distributor: Delco 423R Echlin RR-182R Niehoff DR-53A Borg Warner G152
	Cap	Prestolite Distributor: Echlin AL91 Delco Distributor: Delco D322R Echlin RR-181 Niehoff DR-74
	Coil	Prestolite or Delco Distributor: Delco 070FLX Niehoff DR-180 (standard) Niehoff UN171 (epoxy heavy duty) Standard UC12 Specifications: Primary Winding: 12 volt, 3 ohms
	Distributor	Prestolite distributor (1Gw60032E1X) Delco Remy distributor (#1112446 - 2G11/6C16/3HI8) & coil
	HT Leads (spark plug wires)	Atomic Four Engine Service A4HTset Specifications: Wire type: 7 mm high tension wire, carbon core resistor type Wire terminals & lengths (add 1 in to length when cutting cable for custom wires to allow for stripping insulation for terminal installation): Coil/distributor lead: straight terminals, 9 in #1 plug lead: straight distributor terminal/90 degree plug terminal, 16.5 in #2 plug lead: straight distributor terminal/90 degree plug terminal, 13.5 in #3 plug lead: straight distributor terminal/90 degree plug terminal 10 in #4 plug lead: straight distributor terminal/90 degree plug terminal 8 in
	Generator	Prestolite 6 or 12 volt generator: obsolete - substitute Delco alternator below: Motorola alternator: Motorola MR12N4510 - type B (Voltage Regulator 8RG 2010A) Wilson rebuild 90-05-9089 (voltage regulator 62-05-9651) Aqua Power rebuild 2834 Specifications: 12 volt alternator (early models were 6 or 12 volt Prestolite generator), negative ground, 35 or 51 amp maximum output, marine-type enclosed brushes behind integral solid state voltage regulator
	Starter	Prestolite: MBG4129 (solenoid Wilson 60-01-6029) Delco: Delco 1107679 Wilson 91-01-3736 (starter drive Wilson 61-01-3455, solenoid Wilson 60-01-3541) Aqua Power 2826 Specifications: 12 volt (early models were 6 volt), negative ground, marine type Note: Prestolite and Delco starters use different flywheel ring gears
	Alternator belt	Dayco: 11A0635 (10A0635 also used) Gates: 11A0635 (10A0635 also used)
	Engine coolant hoses	1/2" id automotive heater hose & stainless steel gear clamps water pump outlet to block water plate "T": 10.5 in block water plate "T" to thermostat housing inlet 90° fitting: 6.5 in thermostat housing outlet to manifold inlet: 4.5 in
	Temperature Sensor (electric)	SW 280ED-F General Marine GEN26630 Aqua Power AP1943 Faria FAR90405 Specification: 1/2" NPT, 12 volt to match control panel temperature gauge
	Oil Pressure Sensor (electric)	SW 279A General Marine GEN24880 Faria FAR90512 Specification: 1/8" NPT, 12 volt to match control panel temperature gauge
	Seawater pump belt (pump over starter)	Dayco: 11A770 Gates: 11A770
	OEM flange mounted water pump - gear driven off PTO unit Used as sea water pump when engine is raw water cooled with no heat exchanger. When heat exchanger is fitted used as engine coolant pump, except when electric pump is fitted, when it is used as sea water pump and electric pump is used as an engine coolant pump.	After 1969 OEM pump was Oberdorfer 202M3 (2 US gal / minute, 15 psi max @ 1,000 rpm) Cam thickness .105 in (half cam) Note: 202M3 is usually upgraded to Oberdorfer 202M7 when rebuilt or replaced by installing M7 cam. M7 was used on older diesels Oberdorfer 202M7 (3 US gal / minute, 20 psi max @ 1,000 rpm) Cam thickness: .150 in (full cam) Impellor: Oberdorfer B6593 West Marine 241044 Globe 815 Barco 815 Sherwood 295628
	Sea water pump used with heat exchanger: belt driven off pulley on end of crankshaft at flywheel, driven directly off end of crankshaft, belt driven using alternator drive belt, or electric motor pump	Sherwood R30G / Jabsco 2620-1001 / Oberdorfer 201M (or any pump with a continuous capacity of 6 US gal / minute @ 1,800 rpm and a rpm rating of at least 3,000 rpm) water pump / crankshaft pulley ratio: 1:1
	Carburetor Jets	1948 – 1968 Zenith 61-M2AE7: main jet #24, Zenith C52-6-24 & adjustable needle assembly idle jet #10, Zenith C55-6-10 (.019 in drill size) well vent jet #22, Zenith C77-18-22 (.043 in drill size) main discharge nozzle #50, Zenith C66-26-1-50 1969 – 1984 Zenith Bendix 68-7: venturi #16 float needle & seat #25 main jet #21, Zenith C52-7-21 (.041 in drill size) idle jet #12, Zenith C55-22-12 (.023 in drill size) well vent jet #21, Zenith C77-18-21 (.041 in drill size) main discharge nozzle #55, Zenith C66-114-4-55 (3 x .039 in drill size) idle bleed hole, fixed plug (.039 in drill size)