impeller ? stainless steel or plastic

lquested

Seaman
Joined
Apr 7, 2008
Messages
60
i hear steel impeller is the only way to go is this true or should i stick with the plastic one> thanx for any input.....



ok i feel stupid i guess i did not under stand may be they were talking about propeller not impeller .. and yes i was talking bout impeller.any ways thanks and how much you want for the bridge...lol
 

steelespike

Supreme Mariner
Joined
Apr 26, 2002
Messages
19,069
Re: impeller ? stainless steel or plastic

I've never hear of either one. Outboard impellers are a rubber like material.
 

Frank Acampora

Supreme Mariner
Joined
Jan 19, 2007
Messages
12,004
Re: impeller ? stainless steel or plastic

The water pumps on these engines were designed to use a rubber impeller. The impeller is compressed slightly between the pump housing and the bottom stainless plate. this seals the impeller and housing. The vanes are also larger than the pump housing and are bent backward. They are mounted off center so that the difference at slow speed results in a positive displacement pumping action. At high speed the water resistance bends them backward and the pump now acts as a centrifugal pump. This is also why they last as long as they do and why they are destroyed by running dry.

Even if you could find a stainless impeller to fit the shaft, it would necessarily be smaller than the rubber one and would result in less water being pumped at low speeds. It would also tend to wear the pump housing faster. Increased clearances necessary would result in water bypass and less delivered to the powerhead.

So: if you can find a stainless impeller, I have a bridge for sale in Brooklyn. LOL.
 
Top