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Richard Casady

On Thu, 22 May 2008 12:06:29 -0400, wrote:

On Thu, 22 May 2008 15:42:48 GMT, (Richard
Casady) wrote:

On Wed, 21 May 2008 22:16:49 -0400, wrote:

On Thu, 22 May 2008 01:11:53 GMT, (Richard Casady)
wrote:

On Sat, 17 May 2008 07:21:53 -0400, wrote:

You should plan on replacing the impeller every other season regardless of
anything else, including whether the motor was even used or not. It's not a hard
job, but it's an important bit of maintenance.

10 000 miles in a car, at 50 MPH is the same two hundred hours that is
a lot for most small boats. The family ride reached 170 000 miles with
a set of spark plugs that it didn't need, at 100 000 miles. Then it
developed low compression on one cylinder, and I figured the writing
was on the wall and had them put in a rebuilt motor with a warrenty.

Used up a motor with lots of miles, but the water pump never caused
trouble.

Casady

Are you on drugs? Seriously!

I seriously believe that water pumps shouldn't wear out in only a few
hundred hours. How many hours is 170 000 miles? Yacht engines get used
little on the average. 200 hours per year is one figure I read. The
family auto and everything on it have been trouble free for about
5000 hours Gas oil and tires and that was it. Why are boat pumps ****?

Casady

The impeller in a car waterpump is METAL, for openers. Outboard
waterpumps have to work in a very different environment, and so they
are made of flexible materials. They are in contact with the insides
of the pump housing to maintain a needed seal, and the material also
can crack due to plain old aging and loss of flexibility. An outboard
impeller can deteriorate from just age, without having any hours on
it. That's why 2 years is a good time for routinely changing them even
if they have very low hours on them. Likewise, an event where a lot of
sand or mud gets sucked into it, or it is allowed to run while dry
will cause an early death. Running dry ruins them almost instantly.

They aren't ****.
Good.
They are designed for a different set of rules than
a car water pump. Boats are not automobiles, nor are they airplanes.

That plastic impeller can perhaps have plasticisers leach out over
time, making the thing brittle. I thought all the parts of the car
were connected to the odometer so they can hang on to existance until
the warrantee is up.

Casady