that's the quiet drive no issues lol

Thanks for mentioning the crack in the race..That got by me .Any comments about the oil level. The one with the cracked race had oil filled to the top no issue on that drive at all . The noisy drive had oil only to the bleed port.So how does the oil lubricate the gears etc above the oil bleed port? or was that area of my drive air bound and should have filled all the way like the other drive.

So i also decided not to remove the shift fork mechanism..I really doubt that fork is making that much noise engulfed in oil.

This all started with a u-joint i wanted changed because i am a nut with keeping up with maintenance

Anyone have a bravo 1 cheap LOL....

I was looking for an answer on the noisy drive and now you found a problem with the quiet drive..lol Now i have 2 drive problems....lol Thanks for finding that

You could pour gear lube in the drive onto the upper gears with the top cap off so it matches the other drive, and see if the noise persists.

I’ve also wondered how long it takes for the lube to fill the upper so both the top and lower gears are submerged in lube. Seems when pumping new lube in once it reaches the valve to the reservoir it doesn’t fill the upper anymore, just fills the reservoir. Then maybe after 10+/- hrs settles back to completely fill the upper?

I did exact that I filled it up like the other drive and it seemed a bit quieter...

I had a bravo X that was full to the very top as well. To the point that just loosening the top cap bolts to remove the drive shower would allow gear lube to seap out from the top cap. Don’t recall the level ever dropping in the reservoir either.

Does it have anything to do with the gear lube bottle height in relation to the drive?

The bottle never changed oil level

My mechanic said if the race is no longer pressed on the cap tower then that cap is NG. That means the race was spinning on the cap tower. Time for a new cap. Kind of glad i pulled the cap off at this point but the other drive still has an issue. Thinking of whats inside of the drive shaft assembly, top bottom gear, clutch, springs spacers .I can't imagine what can make that rattling noise that is so noticeable even with the loud exhaust. To me it sounds like something is hitting the inside of the housing. The shift fork hangs in the center of the clutch.and i can't picture the top or bottom gear rocking back and fourth at 750 rpm idle to cause that knock as shown in the video top cap off when the engine was off. BTW, A rep from mercury marine said this to me. Even thought the engine is idling it can cause the gears to rock back and fourth probably due to an engine adjustment or could be just your engine. I can't imagine that either. If the engine is turning lets say Left Hand, that means each gear is touching the interlocked gear it rides on, so at 750 rpm how in the world are you going to get a rocking, chatter from that? This drive shifts perfectly no slippage, Running at any rpm no unusual vibrations.I'm lost?

Not one crack but 2
 

Took the cap off the other no problem drive and removed the cracked race out of the top gear bearing. Bearing looks good and turns smoothly.. This is the drive that was filled with oil to the top, maybe that saved the bearing needles. The bearing in the cap does not feel right. It is rough turning and jumpy. Maybe it froze up at one point and caused the race to spin and crackhttps://cimg1.ibsrv.net/gimg/www.off...3de26354e9.jpg
https://cimg2.ibsrv.net/gimg/www.off...188aa200a5.jpg
https://cimg3.ibsrv.net/gimg/www.off...e32f1fb61b.jpg
https://cimg4.ibsrv.net/gimg/www.off...49bb2efce5.jpg
https://cimg5.ibsrv.net/gimg/www.off...a9eea20ab4.jpg

this is the other drive the one that had no problems.Starboard, I just pulled the top cap to swap them and now i have 2 drive issues.
At this point since i won't be going boating now i just may pull the fork on the noisy drive

If it had an air leak then wouldn't water enter, wouldn't you see a stream of oil sitting in the water engine off, and wouldn't the level of the bottle drop. What pumps the oil up to the top bearing in the cap? That air gap between the vent hole and the top of the drive, that air is supposed to work its way out through the bottle.
According to a merc mechanic you fill the drive to the vent hole then you make sure the level in the bottle is correct. After a few runs the level in the bottle will drop because there is air inside the top of drive and eventually that will come out.So you will have to add oil. I used to do it that way but now I drain the oil from the drive and i remove the cap on the oil bottle. The bottle should drain also if it is working correctly. Then i fill from the bottom of the drive and after it comes out the bleed hole i cap that and i keep pumping until i see 1/3 of the bottle filled. This way it gives room for expansion.You may have to add a bit a few times. I have friends that don't even take out the bleed port. They just fill it to the bottle mark and that's it. I think that oil level in my drive saved the drive from blowing up.

I have always just filled them from the bottom until the reservoir was half full. Never saw the need to remove the top plug.

I think I found something
 

Today I took the noisy drive apart. I removed the shift fork for a test on the rattling noise. When i pulled the top cap off I noticed the race on the cap was different than the other drive. The race was wider and thinner and when it was on the cap it was lower than the casting. I was told that when you install these caps the race presses against another type of washer with needle bearings and it pushes down on the gear assembly setting also lash. So how could the race that was on the cap sitting below the casting push down on anything. I looked up these race's on Mercruiser parts and they make 3 different sizes. starting with .091, .094, .097 thicknesses. I got a new cap for the other drive that had the cracked tower race and the guy whom I bought it from sent me a bunch of extra stuff. He sent me the needle bearing washers and all these races brand new from Mercruiser No charge. So i started with the .091 race and placed it on the cap. Now it is slightly raised above the casting. Tomorrow will be the real test on startup. see pics + video


https://cimg6.ibsrv.net/gimg/www.off...936fb7bccc.jpg
https://cimg7.ibsrv.net/gimg/www.off...02cd766712.jpg
https://cimg8.ibsrv.net/gimg/www.off...0eb300999e.jpg
.

took it out today...was easy but putting it back maybe an issue...please read my last post interesting what i found
thanks

I thought you had a drive mechanic build these drives?

Shims
 

Is this a 1990's year model,,thin floor housing that has newer thick floor gears installed.

How do you tell if they are the thick floor gears. My serial numbers on the drives start with OD. According to the the guy that owned the boat and redid it back in 2003 he said nothing was upgraded but i did notice a slight difference on the port noisy drive. This drive has the height adjustment on the back where the trim cylinders hook up for bravo 1 or 3. The other drive starboard does not.The boat is a 1992. So what now do I get a set of .051,.054 .057 shims and see which one quiets it down lol
Looking back at the previous pics on the starboard drive with the cracked tower race, looks like the race on the cap is the upgraded style also thinner and wider . So maybe the gears were upgraded
I think I am getting closer to this rattling noise . It's been rattling like this since last summer so it can't be that serious or else it would have blew up by now. Is it possible the race just wore out or should I just take a measurement of that race and order one the next size up?
Look at the height of the race on the starboard side( this drive is quiet no knocking) That's above the casting..The port drive the race was below the casting see previous pichttps://cimg5.ibsrv.net/gimg/www.off...56a40e982e.jpg
https://cimg8.ibsrv.net/gimg/www.off...d064288e85.jpg

I am going to venture a guess without knowing all the facts completely.
Someone installed Thick Floor gears into the OD code Thin Floor housing,, then used the Wrong Shim ,,and did Not use a dial indicator to set the Backlash,, this drive had to be way out of spec,,loose,,

Ok , i agree with you...what is my next step with out taking the drive off and bringing it to my mechanic. Can i install the next size shim after measuring the existing one. Can that do any harm?

The problem is you do not know which shim is needed without using a dial indicator to check backlash,, it needs to be removed to do this,, does your mechanic know hou to correctly install the tower races and shim it correctly.
are welcome to call me so i can explain it,, I rebuild Bravo Drives here.
Mike
618-316-4755

I'm sure he knows how to do the tower races he did not build this drive. This drive came with the boat
The problem i have now is he recently moved a long distance from me and I have no one in my area that does drives that know of
. I'll call you in a little while thanks

Sounds like its time to buy the tools/manuals and learn to do it yourself! I find that's the best way, then you know what you have!!

I'm almost there...bought a lot of tools already lol

Special lubricant 101 no longer available. I think that is the green grease on the shift ball. What do i use to replace that grease?

After doing some research today. I believe i have the Mercruiser gear set upgrade kit part # 883473A4 . My shift fork cam # is 806790 as it shows in the upgrade kit. so this accounts for the wide and thin shims

thanks

New update: NO MORE NOISE....as long as i leave the shift fork out..lol check it out


NOW WHAT ?:daz:

This is not meant to solve your problems but to give a little insight.

​https://www.riverdavesplace.com/forums/threads/max-machine-worx-drive-education.188298/#post-3076273​​​​​​

Good information Thanks!

https://cimg4.ibsrv.net/gimg/www.off...312d21e11b.jpg
When installing the input shaft assembly you must line up the marks on the gears for the timing + top - bottom or - top + bottom.. I was starting to put the cam assembly back in and noticed the - + symbol on the top gear but nothing on the bottom gear. Shouldn't they line up even though they turn in opposite directions. Maybe a cause of my shift cam rattle?

Yes they should line up. It would cause shifting issues if they’re not lined up.

The lines on the gears should be aligned with the 2 marks on the case right in front of the shift shaft at top and bottom. Do you have a bravo service manual?

yes i have the manual and i know the procedure., That + - mark does.t look right to me in the photo..

wheres the +/- mark on the bottom gear?

Got Me? That's what i'm saying SO before i remove the drive I am going to click the engine a few times to see if they align????

This is a learning experience for me....one thing after another!

just pull the drive,loosen the spanner nut and spin the lower gear till they line up.put it all back together and go boating.