boatmon345
Petty Officer 2nd Class
- Joined
- Apr 26, 2006
- Messages
- 113
I have owned this motor since 2004, and I personally rebuilt the powerhead in 2006. Since the boat is kept on a lift, I have never been able to reach the bottom to slip on a pair of ear-muffs to flush it; instead, I have been using the hose attachment all these years.
After my thermostat passages got plugged up after only 11 months, I decided I need to begin flushing the motor using ear-muffs instead of the mediocre way of flushing using the hose attachment (IMHO). As a side-note, I ran the motor after the thermostat repair and it seemed as though I had fixed the problem of the passages being clogged.
Today I received the dual-flow earmuffs, figured out how to reach down to put them on and take them off, then I flushed my motor for the first time using earmuffs. So with the motor completely out of the water, and water going to the muffs, I ran it and it and the telltale was strong. 5 or 10 minutes later my overheat alarm sounded so I shut it off and realized that the thermostat housings were very hot and indeed the motor was too hot.
I come to find out that flushing like this was causing no water to be expelled from the two above-water exhaust ports, but as soon as I lowered the prop so that it was underwater, the 2 exhaust ports began spitting out water and the engine no longer overheated. It is as if the back-pressure of the sea water resisting the exhaust coming from the center of the propeller caused the exhaust and water to be re-routed through the 2 above-water exhaust ports. I could not get it to overheat with the prop underwater, but again, as soon as I raised the lift raising the prop out of the water, the above-water ports stopped spitting water and I felt that it would overheat if I left it like that.
And yes, I had plenty of water going to the dual-flow earmuffs, and they were aligned overtop the impeller intake just right.
Can someone please explain why I cannot ear-muff-flush my motor with it fully out of the water?
EDIT - Additional information:
I forgot to mention that I tried a small test. I took the earmuffs off, lowered the lift to about so that the water was an inch over the flat horizontal part of the lower unit, and ran the motor in forward-gear at about 1200 RPM (please don't flame me - I know it could be dangerous if not done properly). I was a little shocked to see that as soon as I went from neutral to forward, water stopped being expelled from the exhaust ports. As soon as I put it in reverse or neutral, water would come from the exhaust ports like usual. I didn't run it long enough in forward gear to see if it was getting too hot.
What could all this mean?
After my thermostat passages got plugged up after only 11 months, I decided I need to begin flushing the motor using ear-muffs instead of the mediocre way of flushing using the hose attachment (IMHO). As a side-note, I ran the motor after the thermostat repair and it seemed as though I had fixed the problem of the passages being clogged.
Today I received the dual-flow earmuffs, figured out how to reach down to put them on and take them off, then I flushed my motor for the first time using earmuffs. So with the motor completely out of the water, and water going to the muffs, I ran it and it and the telltale was strong. 5 or 10 minutes later my overheat alarm sounded so I shut it off and realized that the thermostat housings were very hot and indeed the motor was too hot.
I come to find out that flushing like this was causing no water to be expelled from the two above-water exhaust ports, but as soon as I lowered the prop so that it was underwater, the 2 exhaust ports began spitting out water and the engine no longer overheated. It is as if the back-pressure of the sea water resisting the exhaust coming from the center of the propeller caused the exhaust and water to be re-routed through the 2 above-water exhaust ports. I could not get it to overheat with the prop underwater, but again, as soon as I raised the lift raising the prop out of the water, the above-water ports stopped spitting water and I felt that it would overheat if I left it like that.
And yes, I had plenty of water going to the dual-flow earmuffs, and they were aligned overtop the impeller intake just right.
Can someone please explain why I cannot ear-muff-flush my motor with it fully out of the water?
EDIT - Additional information:
I forgot to mention that I tried a small test. I took the earmuffs off, lowered the lift to about so that the water was an inch over the flat horizontal part of the lower unit, and ran the motor in forward-gear at about 1200 RPM (please don't flame me - I know it could be dangerous if not done properly). I was a little shocked to see that as soon as I went from neutral to forward, water stopped being expelled from the exhaust ports. As soon as I put it in reverse or neutral, water would come from the exhaust ports like usual. I didn't run it long enough in forward gear to see if it was getting too hot.
What could all this mean?