Harley Davidson 1940-58 45" SV & SERI-CAR. Service manual - page 2
If seat is refaced with a cutter it will not be as smooth as when
refaced with a grinder and a greater amount of lapping will be necessary
to attain a perfect seat.
When a new valve guide is installed, it is not likely to have exactly
the same relation that the old guide had to valve seat. Therefore, it is
especially important, after fitting new guides, that seats be carefully
refaced to make them concentric with guides and assure perfect alignment
and matching of valve face and valve seat.
Testing Valve Seating
If valve seats and valve faces have been smoothly and accurately refaced
with grinders available for this purpose, very little grinding or
lapping will be required to complete seating operation. Apply a light
coat of fine compound to valve face, insert it in cylinder and give it a
few oscillations with a screwdriver—just enough to give face and seat a
lapped finish. Remove valve, wash valve face and seat thoroughly with
clean gasoline and allow to dry, or dry with compressed air. If
inspection shows an unbroken lapped finish around both valve face and
seat, valve is well seated. If lapped finish is not complete around
either valve or seat, further seating is required.
Valve Springs
Inspect each spring in comparison with a new one; if a spring is
shrunken more than Vt". replace with a new one.
Re-installing Valve Assemblies
To re-install valve assembly in cylinder, reverse removal procedure. Be
sure all parts are clean. Valve sects and stems should be lightly oiled.
Install new seals between upper valve covers and guides; also, if
needed, new packing between valve covers.
Caution: Intake and exhaust valves are of different materials and must
not be interchanged. Intake valves are marked (IN) on head; exhaust
valves are marked (EX).
Timing Gear Shaft Bushings
Check timing gear shaft bushings in right side crankcase and timing gear
case cover for extent of wear. These bushings normally do not require
renewal until an engine has run extremely high mileage. However, if
engine has been run under dusty conditions and, as a result of lack of
attention to air cleaner, considerable road dust has been taken into
engine through carburetor, abnormal wear may be found at any mileage.
Specified clearance for camshaft bearings is .0005” to .001". When
bushings are worn to the extent of increasing clearance to .002" or
more, they should be renewed, as the cam gears are likely to become very
noisy with excessive clearance in these bearings. Worn bushings in case
and cover, with both
ends open, can be pushed out with an arbor press, supporting case or
cover on a suitable collar or sleeve at the flanged end of bushing.
Bushings in cover, with o.ie end blind, must be pulled with
manufacturer's special tool number 11952-36.
Before removing old bushings, note location of oil transfer hole in
pinion shaft bushing in timing gear case cover. New bushing must be
installed with oil transfer hole in same location (30° ahead of vertical
center line), as normal function of oiling system depends upon correct
location of this hole.
After new bushings have been pressed in they must be dowel pinned to
prevent them from turning, by drilling a hole with a number 31 drill
through bushing flange and into aluminum. The hole should be of a depth
so when dowel pin (part number 661-31) is driven in and bottomed, its
end will be slightly below face of bushing flange. Peen bushing around
dowel pin hole to prevent pin from coming out. Oil holes for lubrication
of cover bushings will have to be drilled in three of the bushings,
according to holes already in bushing bosses.
Attach cover to right case and line-ream with special reamers,
manufacturer's numbers 12135-37, 12133-37 and 12132-36.
Valve Tappets and Valve Tappet Guides
Inspect valve tappets for excessive clearance in guides. Also check
tappet rollers for excessive bearing looseness and damaged roller faces.
Tappets and tappet guides are normally long-life parts that seldom
require replacement. Tappets are originally fitted with .0005" to .001"
clearance in guides. Guides ате a light press fit in crankcase and are
secured with screws. To remove a lappet, it is first necessary to pull
tappet guide out of crankcase. After removing screws, heat case around
guide, and pull with manufacturer's tool number 11960-38. Cam gear must
be assembled in case for tappet to butt against when using puller.
Excessive tappet-guide clearance is serviced by fitting new tappet, and
new guide if needed. It is also recommended practice to renew tappet
complete
