Seahawk 34 gearbox?

[wragges]

Hi All,

Can anyone tell me what the standard gearbox type and ratio is...on a Westerly Seahawk 34 (bolted to a Volvo 2003)?


....and is it white?....ours is white (engine is volvo green) and I suspect the box may either not be the original, or may have been overhauled.

Thanks,

 

[john_morris_uk]

Volvo often use Hurth Gearboxes as original equipment and they are often white as original fit. However this doesn't guarentee anything. Similarly as regards the ratio, you need to look on the gearbox itself. Its on a brass plate stuck on or rivetted to the top. Even if you find another Seahawk owner with a similar engine and a Hurth gearbox, then you still need to double check your ratio. I am told that Westerly were very good at fitting what was available and perhaps altering the pitch of the propellor to suit the gearbox they'd put into the boat. They certainly didn't stick with one manufacturer for fitting out. Our gearbox is white and its original to the (Volvo) engine if that's any help.

The gearboxes are normally very reliable but the clutches wear out eventually. Does it look something like this:

 

[Steve_N]

The standard gearbox type would have been a Volvo Penta MS2B. They are white.
Can't help with the reduction ratio though.

 

[Steve_N]

This is an MS2B:

 

[pvb]

The standard Volvo Penta MS2B gearbox was available either with a straight output shaft (ie parallel to the crankshaft) or a downward-angled output shaft (7 degree angle). The straight type was 2.3:1. The angled type was available with either 2.4:1 or 3.0:1 ratios.

 

[Fr J Hackett]

Crank the engine over by hand and count the number of turns to give on revolution of the prop shaft, use a pair of marks better if the boat is out of the water and you can use the tip of one of the prop blades against a suitable mark. If the suspected ratios are close eg 2.3 or 2.4 : 1 you will have to crank the engine over a number of revolutions to determine the difference. ie 23.