Disassembling Engine For Top Overhaul Only

Disassembling O.H.V. Engine

(If motorcycle is used with sidecar or package truck, remove it.) First perform operations 1 to 8 inclusive, under "Removing Assembled Engine From Chassis for Complete Overhaul," Page 41.

9. Remove oil pipe at rocker arm housings and gear case cover.

10. Remove manifold and carburetor: If motorcycle is eguipped with oil bath air cleaner, disconnect air intake hose connection fitting from carburetor and leave attached to hose. Remove air cleaner bracket together with oil bath air cleaner and hose.

Remove nut seeming carburetor support bracket to crankcase top center bolt. Unscrew manifold nuts, using Harley-Davidson special wrench. Part No. 12002-40.

11. Open push rod covers. Press cover expander sleeves down and remove push rod cover keepers. Telescope lower push rod cover over upper cover.

12. Remove cylinder heads: Turn engine until both valves are closed in front cylinder head. Remove cylinder head bolts, using Harley-Davidson special wrench. Part No. 12650-29. Remove front cylinder head, valve push rods and push rod covers in one operation. Follow practically the same procedure to remove rear cylinder head except after head bolts have been removed, twist head to left to free valve push rods and push rod covers. There is not enough clearance between rear head and frame to allow lifting head straight up as is the case with front head. Mark push rods in some manner to identify them as to which cylinder head and valve they were taken. If push rods are reinstalled in same locations from which they were removed, a minimum amount of valve adjusting should be necessary.

Note: If the cylinder heads do not come loose on removal of head bolts, tap lightly with rawhide hammer under aluminum rocker arm housing bracket to loosen. Never try to pry head off.

13. Clean crankcase around cylinder bases and push rod covers to prevent dirt from falling into crankcase when lifting cylinders.

14. Remove cylinders: Remove all cylinder base stud nuts, except one on rear cylinder, using Harley-Davidson special wrench. Part No. ^OSOSO. Raise front cylinder and piston just high enough to permit placing a rag over crankcase opening; this will prevent dirt and possibly pieces of broken ring from falling into crankcase. With piston at bottom of stroke remove cylinder. Remove remaining stud nut from rear cylinder and remove rear cylinder in same manner front was removed. See "Checking Connecting Rod Lower Bearing for Excessive Wear and Looseness," Page 40; "Piston and Pin," Page 88; "Emergency Piston and Ring Service," Page 87; "Installing and Fitting Connecting Rod Upper Bushing," Page 90.

15. Strip cylinder heads: Remove screws and cover plates from spring covers. With screws removed, the straight screw plates are free to come off.

Compress valve springs using Harley-David-son special valve spring compressor, Part No. 12630-36 and remove valve keys from ends of valve stems. Upper and lower valve spring collars, springs and valves can then be removed. It is customary to reassemble valves in same cylinder head from which they were removed; therefore, before removing, mark them in some manner to identify them with front and rear cylinder head.

Check valve guides and valve stems for wear. See "Valve Guides (O.H.V. Engine)," Page 46, and "Valves," Page 46.

If oil seals or valve guides do not need replacing, or rocker arms or shafts do not need attention, no further stripping of heads will be necessary. If in addition to servicing valves and seats, oil seals and/or valve guides need removing, remove remaining nuts and washers that secure rocker arm shafts in their brackets and the cap screws that secure aluminum rocker arm housings to cylinder heads. Drive rocker arm shafts very carefully out of their brackets to free assembly.

Disassemble rocker arm shafts, rocker arms and oil seals. Note order in which oil seals, washers and other parts are assembled in housings and reverse disassembling procedure when reassembling. See "Reassembling Cylinder Heads (O.H.V. Engine)," Page 52.

DIY Battery Repair

DIY Battery Repair

You can now recondition your old batteries at home and bring them back to 100 percent of their working condition. This guide will enable you to revive All NiCd batteries regardless of brand and battery volt. It will give you the required information on how to re-energize and revive your NiCd batteries through the RVD process, charging method and charging guidelines.

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  • Lyle
    How to remove heads from cylinders on harley knucklehead?
    6 years ago
  • Arthur Martin
    How to remove a knucklehead crank seal?
    5 years ago

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