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-   -   Are new gears noisy? (https://www.offshoreonly.com/forums/drives-lower-units/207521-new-gears-noisy.html)

US1 Fountain 04-23-2009 10:17 PM

Are new gears noisy?
 
Rebuilt 1 of my lower B1's with all new gears, bearings and verticle shaft. Pinion depth, backlash and preloads all done by the book. When turning the prop by hand, the lower gears meshing is noticable noisier. It's every tooth meshing that I can hear. Sounds like a drive with no oil. Just curious if this is normal until the drive has been ran under power and the gears have had a chance to break in. Thanks

Mr Gadgets 04-24-2009 04:48 AM

That doesn't sound right.. I setup a used set of gears and they were noisy like that and I put another set in and they were much quieter. I ran the drive with a drill and put a slight load on the propshaft and the noise got much worse...

You know the lash is good. All you can do is run it and see if it quiets down. Are you positive the race seated in front of the driven gear and it isn't causing the gear to be tilted?? That is the only thing I can think of that would cause it.. If it did seat good.. then I can only think it is the gears themselves..
Can you feel them mesh, see any wiggle on the torque meter when you roll it??

Good luck with it.. keep an eye on it, and the magnets. ?? :(

Dick

waconda 04-24-2009 07:04 AM

It sounds like you have them set up to tight and the gears are bottoming out on each other.

endeavor1 04-24-2009 03:48 PM


Originally Posted by US1 Fountain (Post 2851548)
Rebuilt 1 of my lower B1's with all new gears, bearings and verticle shaft. Pinion depth, backlash and preloads all done by the book. When turning the prop by hand, the lower gears meshing is noticable noisier. It's every tooth meshing that I can hear. Sounds like a drive with no oil. Just curious if this is normal until the drive has been ran under power and the gears have had a chance to break in. Thanks

Your gears should make a slight noise when turning by hand but if they are loud, i agree that you may have them too tight. If not, then they go BYE BYE like mine did:angry-smiley-038:

US1 Fountain 04-24-2009 05:20 PM

Everything was setup to specs and double checked. When comparing to my other drive, I'd say it's twice as loud.

Can't say if the race is seated, but I'd have to think it is. I made the race installer with a long shaft on it to extend out the housing by a good amount. I also made a locator that fits in the housing end that holds the installer shaft straight and centered. Then I'll drive the race in until solid.

I didn't see any jumping on the dial while setting the preload and don't feel anything 'catching' when spun by hand slowly, so have to assume there is no binding. If that is what is being meant as too tight; no clearances.

Mr Gadgets 04-24-2009 06:41 PM

What lash specs did you end up with and how much variation around the gear??

The used set I put in and was noisy, I loosened the lash up and it was louder. Another used set and they were quiet..

If it sounded solid when the race seated it is there.. I sand the leading edge on the race so when pressed in, it won't catch any metal and end up under the race. I doubt that happened in your case, since you had a centering device for your driving shaft.

It might just be a bad set of gears.. The monday forging dies.. I am less impressed with merc gears everytime I look at them. :(
If you dont feel any binding, and you know your assembly techiques are solid, I would run it for a while and see if it quiets down. A couple of hours under load and some break in time, might do it. Keep an eye on it, spin that prop every chance you get.. And take a peak at the magnet also..
Good luck.. let us know how it goes.

US1 Fountain 04-24-2009 07:13 PM

Set right at .025 for the pinion height. Checked around the gear at different locations. All was good and same. Plus the noise is consistant all the way around. Not just in spots that would lead me to believe I have some run out/tight spots.
Preload on the veticle shaft @ 4 in. lbs.
Backlash @ .012-.013.
Total propshaft preload was 13 in.lbs. (new bearings) That includes the 4 in. lbs for the verticle shaft preload.

I'll give it a run and check often. Easy to do since boat is kept on lift.



Thanks Dick.

johnnyboatman 04-26-2009 08:50 AM

my bmaxs sound the same, 1 is smooth the other is smooth but not like the other.

US1 Fountain 04-26-2009 11:46 AM

It's just bugging me now, so picked up a new load ring and going to tear it apart for a looky see. I don't want to chance damaging my brand new upper, plus while at the dealership I spun all the B1 drives on the showroom. None sounded like mine.

rhinoLX 04-28-2009 08:04 PM

You sound like you know what you are doing so don't take it "wrong" but is it possible the pinion bearing is not fully seated up in the housing rubbing the pinion gear? I've seen that more than once.


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