Boat2fast
Well-known member
Boaters get into trouble if their engine overheats.
A few things to note about outboard water pumps:
(1) Never run an outboard without the lower unit submerged, or a proper hose connected. Even a few seconds can fry a dry water pump impeller. It is a rubber impeller running on a metal surface. If it is allowed to spin dry, heat builds up instantly.
(2) Never run an outboard that has been found after a long period of storage. Old water pump impellers have a habit of working for a short time and then crumbling into pieces. Off you go, across the lake with Granpa's old motor...it pumped good when you fired it up. Now it's way too hot.
(3) Final, end of season, storage prep: As soon as the boat is pulled out of the water, or as soon as the hose is disconnected for the last time: Spin the engine over with the starter for a second or two. This expels the water from the pump to prevent ice damage. Doing this while the pump is still wet/full won't hurt it. Store vertical for drainage.
Here's are pictures of an undamaged pump and a water pump run dry for a short time. All parts are used. You can tell which ones were run dry. The housing and the impeller were both damaged by the heat.
I don't have the remains of a crumbled impeller to photograph, but I sure have seen a few.
Hope this saves some heartache and expense for someone.
,
,
A few things to note about outboard water pumps:
(1) Never run an outboard without the lower unit submerged, or a proper hose connected. Even a few seconds can fry a dry water pump impeller. It is a rubber impeller running on a metal surface. If it is allowed to spin dry, heat builds up instantly.
(2) Never run an outboard that has been found after a long period of storage. Old water pump impellers have a habit of working for a short time and then crumbling into pieces. Off you go, across the lake with Granpa's old motor...it pumped good when you fired it up. Now it's way too hot.
(3) Final, end of season, storage prep: As soon as the boat is pulled out of the water, or as soon as the hose is disconnected for the last time: Spin the engine over with the starter for a second or two. This expels the water from the pump to prevent ice damage. Doing this while the pump is still wet/full won't hurt it. Store vertical for drainage.
Here's are pictures of an undamaged pump and a water pump run dry for a short time. All parts are used. You can tell which ones were run dry. The housing and the impeller were both damaged by the heat.
I don't have the remains of a crumbled impeller to photograph, but I sure have seen a few.
Hope this saves some heartache and expense for someone.
,,
