Bravo front seal
 

I have a 1990 vintage bravo one and the front seal slides out the front and contacts the yoke and wears a hole in it. this is the second time this has happened, I measured the id of the seal carrier and its the same as two others I have. I know the X drives have a lip on the seal carrier to prevent this, anyone else have this problem or know the fix?

Are you using the right tool (driver) the seal sits lower then flush. If its flush with seal carrier yoke will cut into it. Hope this helps

Yes, as i recall i think I had a problem with one in the early 90's and maybe a service bulletin?

Could you try using Loctite Bearing Mount 609 on the seal? Used it on other things before and it works great.
http://www.allbatterysalesandservice...fm/4,5540.html

sac,
When I install a new seal, I take carb cleaner and lightly wipe the surface of the seal contact area to clean up the coating that is on the seal. I then apply red loctite to it and then press the seal in. With the proper driver it will be slightly recessed into the holder. I have not seen any move with that install procedure
Some have taken a punch and make some light indentations to the retainer to help hold the seal in. Becareful doing that, it could ruin the retainer.
I think there may be some aftermarket retainers that have a lip for the B1 seal, but I have never had a need for one. The 271 Loctite seems to do the trick.
Hope that helps.

The Bravo Shop has a new style seal retainer to hold the seal in place for the early Bravo 1's.

I pulled the upper off of the lower and the upper has the oil passage hole tapped with a plug in it since the lower has no oil passage, I wonder if the upper is getting hot and letting the seal move forward. The port drive has no oil passage in the upper or lower and no problems with it.

Take a look in the space that the vertical shaft connects to the upper clutch shaft. On a newer upper that has the oil passages you are talking about, there will be one hole drilled in the side of that space. On the older cases, before the oil passages, there is another hole on the front side of the space. If it isnt there and your oil passage is blocked. It might not be a bad idea to drill that extra hole.
The oil passage from lower to upper is for the natural circulation of oil caused by the lower gears acting as an oil pump. Without that passage there is no flow to the pinion bearings on the input pinion gear in the upper. I am not sure what Merc had in mind with the older cases, but when ever I find a mismatch like you have, I add the second hole. It could be a cause for heat.
Have you ever noticed one drive hotter than the other? White chalk on one or the other? Are you running drive showers?
The seal retainer plate from Bravo Shop would solve the moving seal, but if there is another issue, that should be addressed as well.

Not sure I have pictures of what I am talking about, but I may be able to find some if needed. Let me know..
Hope that helps.
Dick

We are building a seal set for the Bravo units. We have Engineered the seal to be s.s. with two lips and two springs, one inward and one outward. The outer helps keep the oil in but also keeps water out and off of the yoke. the seal will be mounted in a shell with an external lip to prevent it drifting into the yoke.
I wish I could sell you one now but the seal is being tooled as you read this. We will also have a seal for the xr smaller seal size but also double seal lip. We built the special double seals in the Alpha yoke seal sets which we have had for years. All three seals in the set are rubber coated s.s. double lip, double springs. When installed it places six instead of three seals and located to miss old grouves cut into the seal surfaces of the yoke or shafts. check here
thanks Buddy