Bravo 3 water pump

[Dave R]

Originally Posted by Rusty

Do you have all the tools necessary to pull the Gimbal bearing and and check the alignment?

I have a couple of alignment tools if anyone ever needs to borrow one. They work for both VP and Merc. One tool is a special one that I designed for figuring out gross misalignments. Works great if you can't figure out which way to adjust when a standard tool just won't go in.

Gimbal bearing comes out pretty easily with a slide hammer.

[Rusty]

Originally Posted by Dave R

I have a couple of alignment tools if anyone ever needs to borrow one. They work for both VP and Merc. One tool is a special one that I designed for figuring out gross misalignments. Works great if you can't figure out which way to adjust when a standard tool just won't go in.

Gimbal bearing comes out pretty easily with a slide hammer.

The only thing a good mechanic needs in his tool box is a small hammer and big hammer.

Slide hammers work Ok if you get behind the bearing evenly. I've seen some DIY's make a mess using a slide hammer.

Could you post some pictures of the special designed alignment tool that you made?

[Dave R]

Originally Posted by Rusty

The only thing a good mechanic needs in his tool box is a small hammer and big hammer.

Slide hammers work Ok if you get behind the bearing evenly. I've seen some DIY's make a mess using a slide hammer.

Could you post some pictures of the special designed alignment tool that you made?

I don't have a pic of the alignment tool. It's just two pieces rather than one. One part is basically a machined steel pipe that has an OD that just fits in the bearing, the other part fits perfectly in the steel pipe and also fits in the coupler. If you use the inner part in the coupler without the pipe part, you can easily tell which way to make gross adjustments.

The slide hammer I was referring to is a special tool for removing bearings. Like this:

[mowtorman]

Here's the pump and impeller. The spindle is similar to the blade spindles on a lawn tractor, and the bearings can fail in a similar manner. The impeller housing is plastic and bolts to it. It can be very difficult to access depending on the brand of boat. You can see two old impellers. The fins become brittle as the rubber dries and hardens and break off with time as you can see. When they break off the pump partially works for a short time before it disintegrates. The pieces can end up in the thermostat housing and block the flow of water to the exhaust manifolds which can crack. Definitely less expensive to pay ahead on preventive maintenance let alone the possibility of getting stranded and having to get towed on a beautiful summer day.

[Dave R]

Originally Posted by mowtorman

Here's the pump and impeller. The spindle is similar to the blade spindles on a lawn tractor, and the bearings can fail in a similar manner. The impeller housing is plastic and bolts to it. It can be very difficult to access depending on the brand of boat. You can see two old impellers. The fins become brittle as the rubber dries and hardens and break off with time as you can see. When they break off the pump partially works for a short time before it disintegrates. The pieces can end up in the thermostat housing and block the flow of water to the exhaust manifolds which can crack. Definitely less expensive to pay ahead on preventive maintenance let alone the possibility of getting stranded and having to get towed on a beautiful summer day.

The 496 pump as described by the OP is different than that one. Advice still applies though.

[NoBozo]

BTW: Running an Alpha I without water will burn/melt the impellor in less than a minute. I'm not making this up. I learned this by doing. NB

[mowtorman]

On the 496. The one shown is a 350 bravo but with basically the same internals and the same issues.

[Dave R]

The bottom of this page shows the three Bravo pump styles: http://www.sterndrives.com/rebuild_b...waterpump.html You (assuming that's your pump in the picture) and I have the middle style pumps (I have a 7.4 MPI).