what's the difference?

[SVFlyAway]

Moving the boat (and you) to Mexico or Costa Rica is great and you don't
need a thermostat at all - actually you don't need too many clothes now that
I think of it.

That gets me wondering about my sanity - why am I now living back in
Seattle!!!!

From: AlbinVega@yahoogroups.com [mailto:AlbinVega@yahoogroups.com] On Behalf
Of Steve Birch
Sent: Thursday, August 28, 2008 2:30 PM
To: AlbinVega@yahoogroups.com
Subject: Re: [AlbinVega] thermostat question..

Just take the thermostat out and GO SAILING

Steve B

 

[groundhogyh]

My water pump turns out to be so weak, that when I tried to install the water strainer between the seacock and the engine, no more water flowed. Just that little bit of extra resistance stopped it. No wonder the motor wants to run hot.

MD6A. New impeller. The pump walls seem smooth.

-What is the failure mechanism for these things?
-Can a bigger, more powerful pump be had that fits the MD6A?
-Are there aftermarket mechanical pumps?

thanks,
roy

 

[n3935j]

How high did you mount the water strainer? Just a thought- may have introduced a air lock into the system. You should have a good flow of water with the inlet side hose disconnected and the seacock open.

groundhog groundhogyh@... wrote:
My water pump turns out to be so weak, that when I tried to install the water strainer between the seacock and the engine, no more water flowed. Just that little bit of extra resistance stopped it. No wonder the motor wants to run hot.

MD6A. New impeller. The pump walls seem smooth.

-What is the failure mechanism for these things?
-Can a bigger, more powerful pump be had that fits the MD6A?
-Are there aftermarket mechanical pumps?

thanks,
roy

 

[groundhogyh]

Hi Patrick,
To mount it, I lifted the cockpit floor. and attached it on the starboard side in the rear engine compartment. About even with where the water pump is on the engine. Only on the wood wall.

The strainer cup seems to fill up just with the outside water pressure alone.
And the idea of an air lock. Not sure I understand. But isn't there naturally air in the line anyway when you start the engine? I do have a drip from the base of the pump, so each time i finish with the boat, I turn off the seacock. Water drains out of the line over time.

I was wondering. If the metal inside the pump wears away over the years, especially the metal on the lid and it's opposite face, wouldn't water be able to move around the flaps?

rb

 

[n3935j]

Rb,
If any component of the water strainer set up is above the water line, you could get air trapped in the line. Easy to check though- just detach the bottom hose at the pump, and there should be a free flow of water with the sea cock open. You might want to pull the cover to ensure that the impeller drive pin is in place and that the impeller turns. The cover gasket could be a problem also, if you have replaced the original gasket with a thicker gasket.
If water is leaking out of the weep hole when the engine isn't running, it would be a good idea to pull the pump off the engine and replace the shaft seals. Kits are available, and it's not a difficult job. If water gets past the inboard shaft seal, it goes right into the crankcase. The result is similar to a leaking head gasket- water vapor and mayonnaise in the valve cover and crankcase breather hose. This happened on my ancient MD6B when I finally resurrected it from the dead- of course what didn't leak when she finally coughed to life after years of sleeping. Removing the exhaust elbow gives you good access to the pump.
The mighty MD6B - a tinkers dream!