[C320-list] Engine Winterizing

[Scott Thompson]

I've had this problem.  Either there is a problem with the impeller or a 
blockage or a priming problem.  If sea water was moving easily then it's 
almost certainly the last.  (I suppose your gate valve could be the 
problem also.)  Any kind of small air leak on the suction side of the 
pump can cause a problem for priming.  A slightly loose hose clamp can 
be the culprit I've found.  Most of the intake hose is (barely) above 
the water line, so a small air leak wouldn't necessarily reveal itself 
through an obvious water drip.

The raw water pump can fail either gradually or suddenly.  Impellers and 
seals and bearings can wear out gradually.  (The belt can start slipping 
too.)  Or you can have a failure of one of the impeller vanes that 
creates a sudden problem.

By the way, I dispense with the bucket in taking a similar approach to 
winterization.  I just run a length of garden hose from a radiator flush 
fitting in the intake line up through the portlight into the cockpit.  I 
put a funnel securely in the end of the hose.  I start the engine and 
start pouring antifreeze into the funnel.  (I have a couple of jugs 
ready to go first.)  I keep this up until pink or purple starts coming 
out the exhaust.  With this method I get a substantial gravity assist 
and so priming is not an issue.


Allan Field wrote:
> When winterizing Sea Shadow for the first time 5 years ago, I cut the raw
> water line about 12 inches forward of the raw water strainer, installed a
> 3-way gate valve, and ran a hose off of the gate valve into a bucket of
> anti-freeze.  I then turn of the engine and turn it off when the bucket is
> empty.  Again, I have done this for 5 years with Sea Shadow and 13-14 with
> my previous boat with never a problem.
> 
> Yesterday I winterized and had a fit getting the engine winterized.  I could
> not get the anti-freeze to start flowing from the bucket.  I even changed
> the raw water impellor but it was fine and not the problem.  I tightened the
> belt to the raw water pump and that was not the problem.  Sea water flowed
> no problem.  Finally, after fiddling around for more than an hour, I took
> the engine up to about 2500 RPM's, got sea water flowing with no problem,
> had the winterizing hose in the bucket, changed the 3-way valve to bucket
> mid-stream and was successful at emptying the bucket.
> 
> The question is what is going on?  Is it possible that the raw water pump is
> giving up the ghost?  Does that pump die slowly or go all at once?  For the
> past 19 or so seasons, I always have been able to winterize at idle speed.
> Any ideas would be appreciated.  Thank you!
> 
> Allan S. Field
> Sea Shadow - #808
> Columbia, MD
> 
>