Does This Sound Right? Bravo Install

I replaced my old MC-1 drive with a used Bravo drive assembly. I installed a new gimbal bearing, U-joints, and drive oil in the new drive assembly. Did the alignment, which maybe that could have been better, but I could pull the bar out with 2 fingers (barely?) and spin the bar without any grinding.

Does this sound normal? Sounds clunky to me. Roughly 900 RPMs.

No, doesn't sound right... maybe try pulling the drive off and see if the noise goes away/changes....But be sure to add water to the intake water hose location at the gimbal bell housing before starting the engine...The idea,

Also try using something like a broom handle, stick, etc. to place around the engine and drive areas to help listen for a more definite sound location.

agreed run it with the drive off. did you replace the gimbal and Ujoints ? if ti sat they may be bad. Ujoints are tough to check out via feel. I have had joints feel great, and when you replace them be beat up. Might pop the top on the drive.

my boat sat for years before I bought it (11ys old with 37 hrs...) when i tore down the drive for a reaseal there was corrosion on the top bearing in the drive that is above the lube level. never saw any signs there was a bad bearing , just when I snagged fishing line on the props shaft I resealed the whole drive...

Agree with those above, does not sound right, run it with the drive off. Does it change when you tilt up or down, or steer left or right? Might be a clue if it's ujoints vs gimble bearing.
I have a mechanic's stethoscope and it is great for finding noise sources.

I did replace the U-joints and gimbal bearing. I also popped the top cap off of the drive. Everything looked fine, but it was hard to see everything in there. I will run it with the drive off once I can, but I just noticed a leaky riser so I have to address that first now

Kola16 said:

I did replace the U-joints and gimbal bearing. I also popped the top cap off of the drive. Everything looked fine, but it was hard to see everything in there. I will run it with the drive off once I can, but I just noticed a leaky riser so I have to address that first now

Click to expand...

Could be the gimbal bearing is not fully seated

Okay, I had to chase down a couple other issues I had come up first. My O2 sensor went bad, so I replaced that and it works now. My risers were leaking also and got those fixed. The studs had loosened so I replaced the gaskets (and O2 spacers) and all is well again.

Now to the noise. I casted my own bearing driver install tool out of aluminum since I did not have one before. I used a punch to install the bearing initially which I do not recommend to anyone else if you read this. I also casted some new spacers for the O2 sensor for my EMI Thunder exhaust.



I put the new tool on the alignment bar and gave it some good whacks. Did the alignment all over again. Still not smooth like butter, but as good as it is going to get. Put the drive on and still the same noise. I was pretty bummed. I am going from a MC-1 drive to a Bravo so the Bravo stuff is new to me. The propshaft was spinning and I thought that was kind of weird so I took the lower shift cable off and manually pushed it into neutral and presto! The noise is gone. Apparently my preadjustment of the shift cables was a little off and the clunking/knocking noise was the drive trying to go into the reverse gear. I have forward neutral and reverse all working now, and there is no clunking in any of them. Hopefully I did not mess up the shifting clutch mechanism at all by running it for 5 minutes and not knowing that it was trying to go into gear.