INSTALLATION INSTRUCTIONS For Rivera Engineering's Dual 42mm Mikuni Carburetor kit 12532 Lambert Road, Whittier, CA 90606 (562) 907-2600
DUAL CARB INSTALLATION 3. GASOLINE IS EXTREMELY FLAMMABLE. GASOLINE VAPORS ARE EXPLOSIVE. Before attempting to install or service your Rivera dual-carbs, please follow these fire safety procedures: SAFETY PROCEDURES NOTES, CAUTIONS and WARNINGS Instructions in this manual preceded by these words are very important. ยท Make sure your work area is well ventilated and free from any source of flame or sparks, i.e., appliances with pilot lights, such as water heaters, clothes dryers or space heaters, etc.
DUAL CARB INSTALLATION NOTE Having less than 3/8" gas tank clearance may allow the carburetors to contact the gas tank as the engine moves during normal operation. Before inserting the carburetors into the intake manifold, make certain that the choke cable is positioned pointing downward, between the carburetors and intake manifold. B. Insert the carburetor spigots into the manifold spigot seals with a slight rocking motion. D.
DUAL CARB INSTALLATION vacuum fitting Item 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22A 22B 22C 23 24 25 26 27 28 29 30 31 32 capped purge fitting E. PURGE FITTINGS - These are installed in both carburetors and factory capped (as illustrated above). To connect your evaporative emission system to the dual-carbs, remove a cap from one of the carburetors and connect the purge hose to one of the carburetor fittings. If a longer purge hose is required, use the remaining piece of vacuum hose.
DUAL CARB INSTALLATION CARBURETOR PARTS LIST 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. 63. 64. 65.
DUAL CARB INSTALLATION DUAL CARB INSTALLATION smooth, steady idle with the screw between 1 turn and 2 turns out from fully bottomed (gently!). If the engine requires more than 3 turns out, the pilot jet is too rich (large). If it requires less than 1/2 turn, the jet is too lean (small). BASIC PRINCIPLES OF CARBURETOR OPERATION As air passes through a carburetor, fuel is introduced to obtain the correct air-fuel ratio. This is accomplished with the help of a venturi.
DUAL CARB INSTALLATION air screw adjustment procedure, the resulting adjustment will probably be on the lean side of correct. If you have a large fan, use it while adjusting the mixture. If you do not have one, you may need to take time out for a short ride to cool the engine back to normal temperature. CAUTION There is little point in attempting to tune carburetors unless the engine is completely sound.
DUAL CARB INSTALLATION The jet needle position will be near correct when acceleration is crisp at mid rpm yet the engine does not load up during throttle shut down. portion has its range of operation. The tapered portion has an increasing effect on fuel mixture from about 1/4 throttle opening as the tapered section leaves the opening of the needle jet. Between 1/2 and 3/4 throttle the influence of the jet needle is the greatest and it controls most of the fuel flow. DUAL CARB INSTALLATION B.
DUAL CARB INSTALLATION FLOAT LEVEL ADJUSTMENTS DISASSEMBLY 1. Remove the air cleaner assembly by removing the chrome outer cover and the air filter element. The fuel level of the carburetors will probably never need adjusting; however, if a problem has been diagnosed as a fuel level that is too high or too low, adjustment can be done as shown. 2. Remove the two socket headed alignment screws. Remove the air cleaner backing plate by removing the center bolt after loosening the choke cable bracket nut.
