Pump parts, like impellers, that are under water are usually lubricated
by the water.

Ron

Ron Thornton wrote:
Nothing, thats why you do not run them more tha 30 seconds without water
coming out.

And why impellers require replacement at least every couple of years as
part of preventive maintenance...'cuz even a couple of seconds of dry
friction heat each time wears the edges of the vanes a little...it's not
something you can see just by looking, and there's only a microscopic
amount of difference between vanes that fit the housing tightly enough
to pump water and vanes that don't. Replacing 'em on a schedule
definitely beats being forced to do it when the pump quits...keep the
old one as an emergency spare--'cuz sand or debris can destroy even a
brand new one...applying some teflon grease when you install it helps it
last longer.

--
Peggie
----------
Peggie Hall
Specializing in marine sanitation since 1987
Author "Get Rid of Boat Odors - A Guide To Marine Sanitation Systems and
Other Sources of Aggravation and Odor"
http://shop.sailboatowners.com/detai...=400&group=327

http://www.seaworthy.com/html/get_ri...oat_odors.html

I bet you'de be hard pressed to find anything but trace elements of
teflon on an impeller after it has pumped water for an hour or so.
Lubricate if it makes you feel better but it really only makes assembly
a little easier. Beware what you use though, cause a lub with the wrong
solvents in it can damage it.

I agree with preventative maintenance being important because impeller
pumps are a cheap substitute for a better positive displacement pump.
The tolerances are not nearly in the micro range. That's why even with
the wide range of dimensions that comes from the plastic molded ones
driven by a drill, they still perform pretty well until they completely
wear out.

Ron

Ron Thornton wrote:
I bet you'de be hard pressed to find anything but trace elements of
teflon on an impeller after it has pumped water for an hour or so.


Silicone grease isn't worth a flip, but Teflon grease lasts quite a
while in marine toilets--at least a season, sometimes two--and swimming
pool pumps...so it should last in an impeller housing for a little
longer than an hour anyway. A new shot of it once a month or so
certainly wouldn't hurt.

Lubricate if it makes you feel better but it really only makes assembly
a little easier. Beware what you use though, cause a lub with the wrong
solvents in it can damage it.

Especially any petroleum based lubricant...for instance, vaseline or
WD-40.

Peggie
----------
Peggie Hall
Specializing in marine sanitation since 1987
Author "Get Rid of Boat Odors - A Guide To Marine Sanitation Systems and
Other Sources of Aggravation and Odor"
http://www.seaworthy.com/html/get_ri...oat_odors.html