MerCruiser - Pre-Alpha & Alpha Water Pumps
Both, the
upper housing and water pump service kit, will fit all #1 MerCruiser drives made
from 1967 - 1990.
It will also fit 150hp and larger Mercury outboard motors.
Click
Here For Installation Instructions
Pre-Alpha Water Pump Base
1967 thru 1983
Pre-Alpha bases are both the same. The only difference is that # 3421 has a 3/8-16 threaded
hole going thru it for a motor flusher adaptor. If you have a 1967 - 1970 with
the matching hole in the lower outdrive housing plugged up, and do not
wish to use this for flushing, you can replace this base with the newer # 3417
which does not have this hole.
None of
these bases will fit a Mercury outboard motor !
Alpha Water Pump Base
1984 thru 1990
Alpha uses this base. Notice that the o-ring diameter is about 1/8 larger and
that there is a 1/4 dowel pin in the lower housing which fits into the hole
above. This is to prevent using the earlier model water pump bases which are
smaller in diameter. A smaller diameter base would let water past the o-ring
into the oil.
None of
these bases will fit a Mercury outboard motor !
Complete Water Pump Kits
All
of these kits are the same. The only difference is the lower base.
1967 - 1970 with 3/8 - 16 side threaded hole for flusher
: Order # 2130
1971 -
1983 Pre - Alpha
with pre-load pin on top of vertical shaft
: Order # 2110
1984 - 1990 Alpha with no
pre-load on top of vertical shaft
: Order # 2120
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Here For Prices
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