I got to taking apart my outdrive today and found what I think is a lot of play in the gears, upper and lower, about 1/16". Is that usually a sign of gears about to go? Bravo X off of my 25 Outlaw with 538hrs. Bought it this spring so this is my first time winterizing / changing the gear lube and it was almost completely black. Never seen the Mercury gear lube that black before. When I would spin the prop back and forth this summer with the prop on the drive would make a clunking sound. Figured that wasn't right so I removed the drive. Can't find much info on worn gears for the bravos, only completely broken ones. Thanks for the help guys. I took a video but it doesn't look like I can attach a video right from my phone.

Alright if you're gonna make me post a video
http://s1098.photobucket.com/user/tbringa/media/Mobile%20Uploads/2015-10/9705737D-9452-4108-BA83-33B2699F69B4.mp4.html

You measured that much backlash or you think you have from twisting prop shaft back and forth vs input shaft? You took drive spart or you took it off boat?

The drive is off the boat. The video above is the upper gears, top cap off, with the lover removed. I'm rotating the input shaft with my hand on the gimbal joint. The gears don't appear to have any pitting from what I can tell.

Here are pics of gear teeth with the rear cap off.




Thanks for the help.

With the top cap off, you change the spacing of the gears in the gear stack which will cause excessive lash in the gears. Put the top cap back on, remove the rear cap, and wiggle the driven gears from behind with the top cap on. This will give you a truer feel of the gear lash. Still not an accurate measurement but both should feel about equal.
It is hard to see in the picture, but look at the root of the gear teeth for any kind of tearing. On the helical gears when they are over stressed you can see a fine line of tearing or pitting of the surface. Unlike XR gears that have large pits in them, the helical gears are not so easy to see. It almost looks like a scratch on the tooth surface.
If your lube is black that can be caused by heat or just too long between lube changes. At 538hrs the preload on the pinion bearings has probably gone away and the thrust washer that is between the yoke and the first bearing is spinning. This wear causes the preload to go away and the resultant fuzz on the magnet, in my opinion.
If there is excessive heat in the drive there could be something worn and rubbing to cause it. It would be a good idea to have it torn down and inspected. Normal change interval is usually 25-50hrs depending on usage.
The clunking when you move the prop back and forth could be the cone jumping up and down as you turn the shaft. With new lube you may not hear it as easily. Normal action for a drive is the input shaft turns rather than the propshaft turning the internals. If you shift it into gear and try and move the propshaft back and forth you shouldn't hear any clunking..

Hope that helps.
Dick

Thanks Mr Gadgets. I'll look closer at the teeth and check it out with the top cap back on. The excessive heat theory makes sense to me, cause even with a drive shower the gear housing is turning white.... So to be confident that I won't have a failure I'm most likely going to get it rebuilt or upgrade the entire drive.

The majority of the time that I've send black drive oil, ( on helical gears b1, x) it's been due to the pinion bearings loosing pre load and the washer spinning as Dick just mentioned....it's easy enough to check and fix.

If you guys wouldn't mind please take a look at this link with the diagram and tell me what number the worn out parts you are referring too. It will make it much easier if I know what piece to inspect closer. Thanks and happy thanksgiving!

http://www.boats.net/parts/search/Me...nts/parts.html

It's not shown in your pic. It goes in between the two pinion bearings 30 so that when you tighten the nut 32 it doesn't preload the bearings too much/not enough. Factory shims are brass but use steel. Shim 40 is for setting pinion depth. If you tighten the nut without the shim you won't be able to turn the pinion. Start with too thick of a shim and keep thinning it until pinion turning torque is proper. Used bearing torque is set less than new bearing torque.

The washer that will spin and "self machine" itself when the pinion bearing preload is lost is item # 29 in that picture