ZF Hurth Damper Clatter

The damper plate is the likely cause of the annoying gear clatter on the ZF Hurth transmission, especially at idle power, on the Catalina 34, 36, and other sailboats.

[davide]

Just found this clip hmmmm interesting!
I’ve been aggravated by this noise myself.
I have a Beneteau First 41.5 with a Perkins Prima M50 / HBW10 approximately 30 years old I had the transmission
reconditioned and it never made any difference to the chatter at idle, yes I fitted a new dampener plate. The trans lasted another year before it started slipping in forward, yes I motored a lot. I decided to fit a brand new ZF 12M with another new springless plate from R&D and guess what the chatter was exactly the same . I ran the motor without the trans connected before fitting the new trans and of course it had no chatter. From what I’ve learnt you simple cannot reduce the chatter which is 100% caused by the Perkins
“Torsional Vibration” .
It’s a tiny transmission with a very light/non existent flywheel.
The Perkins M50 should never have been matched to HBW10/ZF 12M .
The ZF15M or ZF25M is a better option especially if your motoring often .
Ps a cooler is a must .

[Houdi]

Importantly, the gear clatter due to poor spline fit is IMHO one of the main causes for shortened life of the Hurth transmission. Other significant causes of shortened ZF Hurth life include: 1) bad engine mounts; 2) poor helm technique, ie, shifting gears above idle; 3) sudden stoppage, ie, a crab pot line wrapped on the propeller; 4) misalignment of transmission to prop shaft, ie misalignment greater than the .003" maximum in the spec.

[cleitonoliveira]

I have a reverser like this on his 20 M brand plate it supports an engine with 150 hp

[johnmoorhousedecorated-nam]

Can the boat be used/operated with the noise?

[adelrajab]

May I ask what engine that Hurth was connected to? When you replaced with PRM120, did you have to adjust engine position? I have a 1985 Catalina 35 with a Universal M25 engine and Hurth HBW50 transmission.

[johnmoorhousedecorated-nam]

Is the noise acceptable? if I increase the idle it goes away, if I place it in gear it goes away