No Water - How Long?

[LaqueRatt]

Think I really messed up. How long can an outboard run with no water without damaging it? Accidentally let my barrel get low and ran for about a min, maybe a little less.

 

[jimmbo]

Don't know if this is what always happens but, you should replace it. An impeller, even a Pump Housing is Cheap compared to a powerhead

A question though, How did you run the engine without noticing the Water was low?

 

[racerone]

At full throttle on a boat you get about 10 seconds if there is a complete , sudden loss of cooling water.-----In a barrel at idle , likely no damage done.----What motor / hp and was it idling ?-----Do compression test.----Replace impeller , go fishing.

 

[Texasmark]

When I was a teenager (young and stupid....ill informed), dad had a 10 hp Scott-Atwater that I used and tinkered with frequently. Over the years, I can't tell you how many times I ran that engine for a brief period dry, or in the barrel in gear blowing most of the water out of it....well below the water pump location, and ran it out of gas out of the water after each use.

I never replaced the impeller and never had an overheat problem. The demise of that engine was one day I was blasting along in my John Boat in a river and the railroad had abandoned a trestle and cut the pilings off such that the tops were about 6" below the surface....mirky water so I didn't see them. In hitting one, it split the mid section in half and the only thing holding the lower half and lower unit on when the boat stopped was the shift shaft.

 

[LaqueRatt]

I'm new to boating. We had them when I was a kid, but that was a long time ago. I was using a big commercial garbage can on wheels, but it leaked real bad around the lift bar on the side. I caulked it up and it seemed OK, but then the caulking blew out. Took me about a half hour to get it started and by then the water was way too low. Turned on the hose right away, but soon realized it wasn't filling up fast enough. So I shut it off. The motor was running above idle at least part of the time. So dumb of me. I'm new, but should have known better. Now the issue is I don't think can get new impellers for this old motor, 14 HP Sears/McCulloch. Is it possible to adapt some other impellers to fit maybe? I hate to scrap this motor, it seems to run pretty well.

 

[Texasmark]

I'm new to boating. We had them when I was a kid, but that was a long time ago. I was using a big commercial garbage can on wheels, but it leaked real bad around the lift bar on the side. I caulked it up and it seemed OK, but then the caulking blew out. Took me about a half hour to get it started and by then the water was way too low. Turned on the hose right away, but soon realized it wasn't filling up fast enough. So I shut it off. The motor was running above idle at least part of the time. So dumb of me. I'm new, but should have known better. Now the issue is I don't think can get new impellers for this old motor, 14 HP Sears/McCulloch. Is it possible to adapt some other impellers to fit maybe? I hate to scrap this motor, it seems to run pretty well.

There is a guy who posts on here that uses Scott-Atwater in/as his Avatar. Other thing is that there are clubs formed around the brand that I have seen, and probably McCullough also. Just dig around the www and I am sure you will not only find any cross-reference, but probably the OEM part .

 

[LaqueRatt]

How long is too long is longer than 1 minute anyway! I guess these are some pretty stout motors. Think I got real lucky. She's pumping water and I'm stoked to get it out on the water.

 

[robert graham]

I cranked my C90 Yamaha dry a couple of years ago and ran it maybe 30 seconds to a minute….so dropped the lower unit to inspect the impeller and it did indeed show signs of heating, as well as the plastic water pump body….replaced both with new for about $30 each….chaulked it up to experience/reminder in the future….That impeller is pretty darn tight inside that stainless steel cup and if run dry you can imagine how quick it will heat up….

 

[jimmbo]

Water is the Lubricant for those Pumps.