Straightening Bent Or Twisted Connecting

kets between carburetor and manifold. Install lock washers and carburetor-manifold screws and tighten screws securely. If these screws are not tight, an air leak will result, causing carburetion to be erratic. Attach carburetor support bracket and tighten securely. Disassemble gasoline strainer—clean thoroughly before installing.

Installing Cylinders (Side Valve Engine)

Lubricate cylinder walls, pistons, pins and rod upper bushings generously with engine oil. Also pour about V* pint of oil onto rod lower ends. This is an initial crankcase supply to take care of lubrication requirements while oiling system is building up normal pressure and circulation, directly after starting an overhauled engine the first time.

Space ring gaps about equidistant around piston but do not locate any gap near exhaust valve port, as in this position ring ends may be overheated and binned.

Turn engine until crank pin is at bottom center. See that crankcases are clean and install cylinder base gaskets. Also note that valve cover gaskets on tappet guides are all in place and in good order. If any are damaged or broken, replace them. Cylinders with valves and valve covers assembled can now be installed over pistons and rings being careful not to change ring gap location. Work cylinders carefully down over rings to avoid any possibility of ring breakage. Install rear cylinder first and as cylinder seats, turn engine so tappets are at their lowest position. Install lock washers and turn on cylinder base nuts and pull them down just snug, not tight. (This is to allow for alignment of intake manifold when installed.) Follow same procedure with front cylinder. In connection with a top overhaul only which does not require removing muffler, insert exhaust pipes into cylinders as they are seated.

Remove top center crankcase stud nut (left side) and drive the stud in flush with crankcase.

Check intake manifold packing bushings to see that they are in good condition. Assemble nuts and bushings to manifold after applying a light coat of oil or grease so bushings will freely adjust themselves to manifold and cylinder nipples as nuts are tightened. Align the hole in carburetor support bracket with top center crankcase stud, then drive stud end through hole in bracket and install stud nut and tighten securely. Turn nuts onto cylinder nipples and tighten securely with Harley-Davidson special wrench, Part No. 12002-30. Unless manifold packing bushings are in good condition and manifold nuts securely tightened there are likely to be air leaks around manifold-cylinder joints. With this condition it will not be possible to get a satisfactory low speed carburetor adjustment.

After manifold is tight, loosen cylinder base nuts slightly to allow final shifting and lining up of cylinders and manifold, then tighten base nuts securely, using Harley-Davidson special wrench. Part No. 12050-30.

Memoranda

Timing Ignition by Piston Position

(To Identify Items, Refer to Illus. 66 or 67—also Refer to Illus. 72)

With front cylinder head removed, engine can be timed by piston position as an alternative to timing by marks as explained under "Installing Circuit Breaker and Timing Ignition (O.H.V. Engine)," Page 81, or "Installing Circuit Breaker and Timing Ignition (Side Valve Engine)," Page 82.

Timing ignition by piston position may be somewhat more accurate than timing by marks only.

test lamp is explained under "Recommended Recheck of Ignition Timing," Page 83.

Timing ignition for front cylinder automatically times ignition for rear cylinder.

Installing Cylinder Heads (O.H.V. Engine)

It is recommended that new cylinder head gaskets be used each time heads are installed. This assures leak-free joints. Old gaskets should be reused only in an emergency when new gaskets are

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