The ZF 15MA replaces the Hurth HBW150 with a 2.5:1 gear ratio or model JS with a 2.47:1 gear ratio. This transmission has a 2.14:1 gear ratio which may require a re-pitch of the prop.

Customers have also used the ZF 15MA to replace the HBW 100 transmission.

Boats that may be able to use this transmission include:
• Catalina 34
• Catalina 350
• Catalina 36
• Catalina 380
• Catalina 390
• Catalina 400
There may be others as well, and not all of the above listed boats can use this transmission. Check the model of your engine to be sure.

Engines that originally used the HBW 150 transmission:
• W-42B four cylinder
• M-38B four cylinder

Engines that originally used the HBW 100 transmission:
• M-35B three cylinder

Critical Dimensions (see "Technical Support" below for detailed specifications)
• Front to back (L + L3) : 208mm (8.17")
• Output shaft drop from crank: 72mm (2.83")
• Reduction ratio: 2.14:1 (the 15M with 1.88:1 or 1.9:1 are no longer available)

Important differences when compared to HBW 150 transmission
• Front to back (L + L3) : +5mm (+0.19685")
• Output shaft drop from crank: +1mm (0.039")
• Reduction ratio 15MA vs HBW 150: 2.14:1 vs. 2.5:1

Important differences when compared to HBW 100 transmission
• Front to back (L + L3) : +12mm (+0.472")
• Output shaft drop from crank: +10mm (0.39") Will require raising the engine 10mm
• Reduction ratio 15MA vs HBW 150: 2.14:1 vs. 1.79:1