transmission for Beta 25

[Jenda]

I have been experiencing annoying noise after re-powering with Beta 25. I believe, that it comes from the TMC40P gearbox. Anybody with similar experience? What do you think about PRM60D, which supposedly has helical gears and costs about the same, as opposed to the straight cut gears in the TMC40. Thank you.

[Pete7]

There is quite an active Facebook group for Beta owners so you might get alot more members who B25 owners or more importantly the 40 box.

Pete

[Jenda]

Thanks Pete,


I'll try, but I usually do not have much luck with technical stuff on FB.

[kmacdonald]

It's not unusual for the gearbox to chatter a little at low RPM's. It should not make noise at RPM's above fast idle. I have a new PRM 125 gear and it chatters a little at low RPM's.

[sailingchiro]

Are you sure it is fully in gear? Mine has done the chatter but needed adjustment for the shifter. It didn't need much (1/8") and the chatter is gone.

[stormalong]

Have you called Beta? They have very good support people.

[Jenda]

I have been emailing with Beta. They blame the prop, that it is singing. So I am trying to work on two tracks. To be ready, when the prop comes back from the shop and nothing is different, what to do next. I think, that the straight cut gear makes the noise. Here is, how it sounds:

http://nebulatechnologies.net/albin/honza/rpm.mp3
http://nebulatechnologies.net/albin/honza/test.mp3
The RPMs called out are on the motor, the gearing is 2.6:1. The sound is there in FWD only.

[Sailmonkey]

Originally Posted by Jenda

I have been emailing with Beta. They blame the prop, that it is singing. So I am trying to work on two tracks. To be ready, when the prop comes back from the shop and nothing is different, what to do next. I think, that the straight cut gear makes the noise. Here is, how it sounds:

http://nebulatechnologies.net/albin/honza/rpm.mp3
http://nebulatechnologies.net/albin/honza/test.mp3
The RPMs called out are on the motor, the gearing is 2.6:1. The sound is there in FWD only.

That’s a singing prop all right.

My cure for that in our new prop was to thrash through a submerged Christmas tree. The blunting of the sharp leading edges stopped our singing.

That’s not a gear noise, the reason it’s not there astern is the prop is interacting with the water with a different edge.

You can replicate the sound with a wet finger run around the top of a wine stem.

[Jenda]

I hope, you are right. It is a brand new Michigan Wheel DJ355 16R11. As for the shifting, I tried direct by hand and it was the same.

[Sailmonkey]

Originally Posted by Jenda

I hope, you are right. It is a brand new Michigan Wheel DJ355 16R11. As for the shifting, I tried direct by hand and it was the same.

We had a new Bauman sailprop, exact same noise. Like I said, went away as soon as I used the prop as a blender.