bravo 3 prop torque

alk

alk

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It's been a few years since I had the props off by bravo 3, so not sure if I'm installing correctly. Just put a new lower unit on, book says torque the inner prop nut to 100 ft lbs. When I get to about 50, I can no longer spin the props by hand. Not sure if I ever remember them being this 'tight'. Something wrong with my new lower, have I always been running to loose, or am I looking at the spec for the wrong nut? thanks.
 
Thanks, this version of the specs help, because i was misreading the torque for the outer nut; but still unsure if i should be able to spin the props by hand with the inner nut at 100 ft lbs?

I cant, but at 50 ft lbs i can.
 
You should be able to spin the shaft. They also should be aircraft locking nuts, so if they're less than 100 ft lbs they're still not going to loosen up. I put mine on as tight as I can still letting the shafts spin. They've not fallen off in 14 years!
 
I haven't done a BIII prop yet but generally, when a nut is torqued to a specific value and a shaft doesn't turn when it should or turns when it shouldn't, The cause may be a thrust washer that got left off.

Just something to check.
 
Nice call Charlie! I was missing the rear thrust washer. I was at the marina this morning walking around asking everyone with a bravo 3 if I could spin their props. Got some strange looks, but both of the ones I tested spun freely. Got home and saw my old lower sitting on the bench, and damn if it didn't have that rear washer still on it. Never did get the boat it the water, will try again tomorrow.
 
When doing my Bravo 3 props I use Mercruiser's Special Lube 101 on everything. Prop shaft, thrust bearings, etc. Also, make sure you time the props. Inner prop blade should be at 12 o'clock or up and outer prop blade should be at 6 o'clock or down in reference to each other. I've found that painting the props with galvanized paint (93% zinc content)helps reduce barnacle growth. Pettit sells a product called Barnacle Buster for around $25, but you can get the same thing in the home centers for around $6 and it's a larger can.Also,your outer prop nut should be torqued to 60 ft/lbs.
 
Heh! Heh! Even a blind pig will find an acorn once in a while.
 
quote:
Originally posted by jtybt15

Heh! Heh! Even a bling pig will find an acorn once in a while.

Click to expand...


LOL... a "Bling Pig?" as in:
$_12.JPG
 
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