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Raw water pump

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bobj

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"i was curious if anyone knows

"i was curious if anyone knows where i can find an inexpensive (not cheap) rebuid kit for my raw water pump, the vanes are all beat up and the bushings appear to be fairly worn also. i would like to replace the faulty parts but cant seem to find them.

also i was curious if with the pump in hand, should you be able to turn it by hand? i could only turn mine if aided by a screwdrive or other on the driveshaft.

thanks"
 
is this the average price for

is this the average price for these items? or can i find them cheaper at a wholesaler?
 
"I just paid for a new pump, $

"I just paid for a new pump, $300.

Check the price on the circulation pump, but take an aspirin before you do ($869).

Ouch."
 
"is it a possibility to just e

"is it a possibility to just eliminate the gear driven raw pump, and install an electric circulation pump in its place? im sure that if hooked up correctly could produce more volume than mechanical pump?"
 
"Nothing is impossible, provid

"Nothing is impossible, provided you "pump" enough money into it. Now I am curious: why do you need more raw water volume? The pump you have now is designed to provide far more water volume than the engine needs. The volume is limited by the pipes' cross section (remember, the narrowest point in a system determines the flow), and any attempt to increase the volume any further is at the expense of increasing the pressure, which would do your system not much good. If there is not enough water circulation at present, I suggest you should either rebuild your current pump, or look for air ingress on the suction side between the pump and the outdrive grids, or look for a clogged exhaust manifold."
 
"Pumping money into the system

"Pumping money into the system as you refer to it is not that great, i can get a 12v water pump for $40 all that i would have to invest other than that is a switch, some wiring and a couple hose connections and clamps. main goal was Not trying to increase volume but cut costs and do same job. perhaps the motor would run better without the extra drag from the mechanical pump.

Similar to a car, a electrical fuel pump is more efficient than a mechanical one."
 
"Personally, I would not recom

"Personally, I would not recommend it as a few concerns come to my mind. The first thing is that you would probably need at least two pumps instead of one. If a mechanical pump has a problem, it is usually the impeller or the seal, and most times you can make it to safe haven without even having to change the parts. With an electric pump the story is different: if it fails you are toasted, and it can fail due to many more reasons than a mechanical pump; so you would need a spare onboard. The motors would have to be explosion proof and probably Coast Guard approved for the intended use. You would also have to make sure the flow and pressure are correct: too much flow will increase the pressure with subsequent erosion in piping and exhaust manifold, and too little....well, that's easy to figure out. Also, remember that the mechanical (attached) raw water pumps are positive displacement and you are probably talking centrifugal pumps, which are not self-priming.

I am of the opinion that when on the water, safety is more important than the pennies you could (questionably) save in fuel by removing the mechanical pump. As the saying goes, if it ain't broke don't fix it. A different story would be a large ship (a freighter for example) where the salt water pumps are most of the times (not always) independent from the main and auxiliary engine, and usually electrical. But again, there are always two pumps installed, and they run from two different sources of power. And contrary to the engine well in a boat, an engine room in a freighter is a comparatively dry environment, far more benign with electrical equipment than a small boat engine well."
 
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