Westerbeke W33 Raw Water Pump Relocation

[sailingjazz]

I have a 84 Westerbeke W33 engine in my Tartan. The water pump">raw water pump is mounted on the timing gear case on the side facing aft. This makes changing the impeller very difficult to say the least. I need to remove the water pump to replace the impeller which would be almost impossible underway. The case has a matching access cover on the front side (facing forward, directly across from the current mounting position) that seems to be the same profile as the access the pump is mounted on.

My question is, does anyone have a W33 with the raw water pump mounted on the front side of the timing gear case? Is it possible to move the pump to the front side? If I move the pump to the front, will it rotate in the correct direction? If it rotates a different direction, will the pump still work?

Thanks
Kevin

[tkeithlu]

No one has answered, so let me take a shot.

Jabsco type impeller pumps are bi-directional. If you have a neoprene impeller of that type, note that the flat at the top of the pump is symetrical, with water being picked up at the top downward motion of the impeller, as the vanes expand outward coming off the plate, then carried around the bottom of the pump housing, and then being squeezed out the discharge as the vanes are compressed by that same plate.


Ergo, direction doesn't matter, but which connection is intake and which is discharge reverses with impeller rotation. Personally, I have to mark that on the pump - if this rotation, that's the intake...

Now for your questions. Yeah, designers, driven by making the inside of a 30 foot boat look like it's 40 feet, leave no space for non-essentials like replacing a pump impeller while approaching rocks in a gale. So, first step is to open the plate and see if the shaft indeed will accommodate your pump. Determine the direction of rotation and then which end is the intake. Then, can you get the hoses to their right positions without routing them around the mast step and the rudder shaft? Is there space for that?

Assemble and test, holding your breath for the momnet raw water squirts out the discharge.

Good luck with it, and take pride in the fact that you are a cruiser who is both concerned about issues like replacing impellers underway and are willing to go out on a limb solving the problem.

[sailingjazz]

So, contrary to the parts diagram I was looking at, the gear which drives the pump only has a spline facing rearward. I took off the inspection plate on the front and I can see the other side of the gear but it doesn't have the spline to drive the pump. I guess if I took the timing gear case apart, I could reverse the gear and have a front drive (not sure this would work but seems possible). I really don't want to take the timing gear case apart. Thanks for the response and all good considerations if the gear had had the drive spline on both sides.

Thanks
Kevin