Engine Replacement Guide
First, pick the Next, match the mount- Third, Last, look at the overall engine data
shaded HP closest ing centers for ease of make sure and make the final selection based
to the original engine. installation. it fits. on the best match.
    # MTG REAR OVERALL   MAX @
MODEL MFG HP CYL CENTERS MTG CTR LENGTH RPM CID TORQUE RPM
7A One W 6.4 1 12/14   25.1 3000 17.7 11.3 2590
P10 W 10 2 14.5 26.12 3000 29.4 20 2000
W 10 Two W 10 2 15 25 3600 27.5 18 2200
11A One W 10.7 1 18.9   23.7 3000 32 20.4 2170
M2-12 U 11 2 14.5/16 23 3600 26 19.5 2600
12C Two W 12 2 14.5   25 3000 38.8 30 2200
W-13 W 13.5 2 14.5/16/18 26.3 3000 27 25 2500
4-60 W 15 4 13/15/18 18 37.5 2500 58 36 1800
M-15 U 11 2 11.5 25.6 3000 31 21.9 2000
W 18 W 18 3 14.5/16 28.4 3300 48 30 2400
20B Two W 18 2 14.5   25 3600 38.8 30 2200
M3-20 U 18 3 11.5/16 25.9 3600 39 28.5 2500
P20 W 20 2 15.5 32.3 3000 58.8 40 1500
M3-20B U 20 3 11.5/14.5/16   26.4 3600 43.8 33 2500
M-25 U 21 3 11.5/16 28.5 3200 52 40 1850
L-25 W 22 4 20/22.75 35.25 2400 97.6 58 2400
RD60 W 22 4 11.5 29.64 3000 60 57 2600
W 21 W 22 3 14.5/16 28.38 3000 60 42 2000
M-25XP U 23 3 11.5/16 27.5 3200 57 43.8 1850
M4-30 U 25 4 11.5/16 29.1 3600 52 39 2600
M-25XPB U 26 3 11.5/16   28.4 3000 61.2 47 2440
30B Three W 27 3 16   28.8 3600 58 44 2150
35C Three W 29 3 14.5/16 29.6 3600 80.4 47 2260
35D Three W 31 3 14.5/16/18.5   31.4 3000 80.4 59 1940
W 27 W 30 3 14.5/16 32.6 3000 80 55 2600
W 30 W 30 4 16/18 18 41 3000 91 58 1800
M-35 U 30 4 11.5/16 31.8 3200 75 56 1800
M-40 U 32 4 16 35.5 2800 91 68 1600
35B Three W 32 3 14.5/16 30.1 3600 68 41 2300
35C Three W 29 3 14.5/16 29.6 3600 80.4 47 2260
W 33 W 33 4 16/18 34.6 3000 91 67 2100
M35B U 35 4 11.5/16   32.7 3000 81.5 62 2460
38B Four W 37 4 14.5/16 33.77 3600 79.6 53 2400
M-40B U 37.5 4 11.5/16   33.2 3000 81.4 73 2180
W 40 W 40 4 16/18 40.5 3000 107 80 2250
44A Four W 40 4 14.5/16/18.5 33.4 3600 107.2 76 1920
42B Four W 42 4 14.5/16 33.78 3600 91 56 2500
44B Four W 44 4   14.6/16/18.6   34.9   3000 107.2 77 2480
44A Four W 40 4 14.5/16/18.5 33.4 3600 107.2 76 1920
42B Four W 42 4 14.5/16 33.78 3600 91 56 2500
W 50 W 41 4 18 3200 110 85 2000
M-50B U 42 4 16   36 2800 113.3 97 1690
42B Four W 42 4 14.5/16 33.78 3600 91 56 2500
M-50 U 44 4 16 36 3000 115 87.9 1600
W 46 W 46 4 16/18/20/22.5 36.72 3000 127 100 2250
W 52 W 52 4 18 39 3000 135 93 2500
55B Four W 55 4 16/18.6   35 3000 133.2 110 1500
55A Four W 55 4 16/18.5 35.2 3600 133.2 93 1920
W 58 W 58 4 18/20/22.5 38.5 3000 154 117.9 2200
W 60 W 60 4 20/22.5 48.5 3000 154 130 2000
63D Four W 61 4 18.5   38.8 4000 144.4 95 1860
W 70 W 70 4 22.5 38.62 3000 182 148 1800
71C Four W 71 4 18.5/20/22.5   39.3 3600 154 118 1950
W 80 W 75 4 20/22.5 51.5 2600 230 170 1700
80-N4 W 80 4 22.5   47.2 2500 262 205 1310
82B Four W 82 4 22.5   38.8 3600 182 146 1890
90A Four W 90 4 22.5   39.3 3600 210.8 168 1670
W 100 W 100 6 22.5 57 3000 247 195 1800
108C Six W 108 6 22.5   54.4 3600 247.2 192 1830
110-T4 W 110 4 22.5   47.2 2400 262 296 1240
W 120 W 115 6 20/22.5 61 2600 346
120-N6 W 120 6 22.5   56.4 2500 396 298 1500
170-T6 W 170 6 22.5   57.5 2500 396 470 1420
5411 U SEE M15
5432 U SEE M40
5444 U SEE M50
M-50A U SEE M50
4-91 W SEE W30
4-107 W SEE W40
4-154 W SEE W60
This information is to be used as a guide only.  Specifications are subject to change without notice and Westerbeke is not responsible for any mis-applications.