[C320-list] Perkins raw water impeller rotation

[Warren Updike]

Alan, sounds like a duplicate of my story only it was 7 vanes from 3
impellers lodged in the heat exchanger.  I had the boat for 3 years with no
problems.  Engine temp even was normal, that is, until that fateful day.
That's when I found the little buggers.  

As for direction of rotation, on my pump the direction is indicated by a
curved line and arrow around the circumference of the cover.  I believe,
from memory, that it is counter clock-wise.  That means the vanes would bend
toward your right.  I'm not sure it matters as once the pump starts I
imagine the vanes will take their proper position.  Pre-bend won't hurt,
though.

Once you have the old one out, I recommend lubricating the inside of the
pump chamber liberally with dish detergent or the like.  This helps during
the initial dry period and provides an indication in the exhaust when the
new water comes through: it will have bubbles. 

Warren & Pattie Updike
1994 C320 #62 "Warr De Mar"


-----Original Message-----
From: Alan Goodman [mailto:goodmanalanlee at hotmail.com] 
Sent: Thursday, April 21, 2011 5:01 PM
To: c320-list at lists.catalina320.com
Subject: [C320-list] Perkins raw water impeller rotation


I am going to install a new raw water impeller on my Perkins, hull #67.
Facing the engine from the cabin (i.e. with my backside visible from the vee
berth, pardon the imagery), which direction does it rotate -
counterclockwise or clockwise?  I want to pre-bend the vanes in the correct
orientation.  

BTW, the PO had changed the impeller prior to last season (which was my
first season), so imagine my horror when I found 4 vanes missing.  Long
story short, I found 11 vanes at the tube stack inlet into the heat
exchanger ... implying that multiple seasons passed without his retrieving
'lost' vanes.  Moral to the story, pull the inlet to the heat exchanger if
you are not the original owner.  I was running a bit hot (200 F) last
season, but there seemed to be adequate water flow out the hull discharge.
I ascribed the slightly elevated temperature to a scaled heat exchanger and
discovered the vanes blocking free flow while dissassembling the heat
exchanger for an acid clean and preparing to flush the engine block (I have
almost 1000 hours).   Lesson learned ... trouble shoot the simple stuff
first !!

Alan hull 67 Holland MI