shooter5636
Cadet
- Joined
- Aug 7, 2015
- Messages
- 27
Hey all,
I picked up a 2001 Yamaha 30hp 3 cylinder short shaft pull start outboard. It needed a water pump or so I thought. The cup, plate, and upper plastic housing were badly worn, so I replaced the plastic housing, rubber grommet that goes inside the plastic housing, impeller cup, impeller plate, impeller, all the gaskets, and thermostat.
On hose muffs it flows fine, but when I launched the boat, the flow out of the tell tale is intermittent. It will go strong, and then gets weak. When you rev the motor in neutral, the flow will come to a trickle and take a second to pick back up.
I disassembled and reassembled the water pump to make sure all was well. The keyway is in place. I rotated the shaft clockwise when setting the impeller in the cup. (Side note, are you supposed to use sealant on the gaskets for the water pump? I was advised against it, but now I'm hearing conflicting advice...
I've idled it with the thermostat as well as with it removed, and no change.
I checked the tell tale hose and it's clear. When I pulled it off the nipple on the exhaust plate it still did the same thing.
I pulled the thermostat cover and thermostat, pulled the lower, and flushed it with a hose from the thermostat port as well as the pickup tube multiple times.
I checked the pickup tube in the mid as best as I could and it's clear from what I can see.
I'm stumped.... Any suggestions?
I picked up a 2001 Yamaha 30hp 3 cylinder short shaft pull start outboard. It needed a water pump or so I thought. The cup, plate, and upper plastic housing were badly worn, so I replaced the plastic housing, rubber grommet that goes inside the plastic housing, impeller cup, impeller plate, impeller, all the gaskets, and thermostat.
On hose muffs it flows fine, but when I launched the boat, the flow out of the tell tale is intermittent. It will go strong, and then gets weak. When you rev the motor in neutral, the flow will come to a trickle and take a second to pick back up.
I disassembled and reassembled the water pump to make sure all was well. The keyway is in place. I rotated the shaft clockwise when setting the impeller in the cup. (Side note, are you supposed to use sealant on the gaskets for the water pump? I was advised against it, but now I'm hearing conflicting advice...
I've idled it with the thermostat as well as with it removed, and no change.
I checked the tell tale hose and it's clear. When I pulled it off the nipple on the exhaust plate it still did the same thing.
I pulled the thermostat cover and thermostat, pulled the lower, and flushed it with a hose from the thermostat port as well as the pickup tube multiple times.
I checked the pickup tube in the mid as best as I could and it's clear from what I can see.
I'm stumped.... Any suggestions?