Reply To: Pre-war Mercury/Wizard gear cases

[green-thumbs]

According to NEW PARTS LIST for MERCURY MODELS manufactured
1939 – 1953 The use of Shim, Prop Shaft Gear Part #15 – 24679 is optional, when required only one is needed and it not used on pre war
twins or KB4-1 or KB5, (steel shim 0.010″)
The bronze spacer and steel shim are used on ALL twin cylinder drive
shafts.
Apparently KD4-1 and later KD twins may or may not need ONE shim
to obtain proper gear lash for smooth operation.
It may possibly be that prior twins could benefit ,but, parts manual does
not show shim as part of the KB5 or KB4-1 or prewar twins.
Louis
Note: the New Parts List was issued by Mercury when it adopted a systematic part numbering scheme in the early 1950s. The 2 prior
part numbering systems were converted to the new system. The New
Parts List, if carefully read, is a source of insight to figure out what is
missing and what is correct for a given model and year. I have found
that there is always more to learn.