Bravo gear set questions
 

Bravo 1. 1.36 ratio 27 and 29 tooth count. I can not find any serial numbers on the case. Are all the gear sets the same or are they model year specific?

Thanks

on the bravo 1/X, there are 3 different upper gear sets 23/30 (1.65) 27/32 (1.5) and 27/29 (1.36)
s/n OM+ have the thicker floor gears

I can not find any numbers on the upper case. Trying to educate myself. So how do you tell the diference in the gears
Thanks

I'm quite sure that the 1.36 gears will only work with an X style input shaft. The standard B1 uses a smaller shaft in the short end. The numbers you are looking for are stamped in the case. They are where the mercruiser stickers are. Sounds like your case has had new stickers placed on it and are covering the original stamp marks.

1.36 gears can be had in X ( larger pinion shaft) and std bravo. ( smaller)

The replacement drives or uppers that I've bought/seen didn't have serial numbers on them....some of the uppers didn't even come with decals.

It's possible you have a replacement.

The only other ways to verify what you have for a ratio is to pull out the pinion, or rear cap and count teeth, or, with the drive off,
shift it into gear, rotate either prop shaft or input shaft til the clutch locks up and compare revolutions between the prop shaft and input shaft.

a 1.36, the input shaft rotates a littler over one and a third of a rotation to 1 prop shaft rotation.

1.5 : is one and a half input shaft rotations to one prop shaft rotation

It's definitely 1.36.
Just trying to figure out if a set of gears I found will work in my case. Thick floor thin floor certain serial numbers are for certain gear sets?
I've only seen pics of the gears I found just trying to make sure they will work before I buy them.

I had a std Bravo 1 with the 1.36:1 gearset, so yes they made them for Bravo 1. The s/n is stamped on the port side case under the decal , close to the bottom of the decal. Hope this helps.

Thin floor gears will have shins in the 90 thousand range i.e. 91-94-96. New gears thick gear will have shims in ( if I remember) in the 60 thousand range. If it's an old case and is stamped say 91.and the shim that in there is not 91 but 61 than someone has change the new gear set.

The gears will fit into the case.

Thick floor gears are all that are that have been available ( new) for quite some time now.

if you remove the back cover of the drive, there will be a 2 digit # stamped above and below the clutch shaft, (unless it's the very last version of the non swept back right around 05'..the aren't stamped)

If those #'s are like 60 through 69 the case was set up with thick floored gears.

if you have thin floored gears, the thick floored gears alone wont work...there's a kit that has the inner tower races, a new clutch and clutch shaft,
the gears, garter springs and bearings that have to be used....you then have to use the thinner thrust races that would correlate to the thickness
of your old thrust races.

There's a bulletin on this...I can find it on line but I'm sure I have it in my collection somewhere

It was under the decal OM109270
The stamped number under the rear cap I believe was 60