After buying a used Suzuki 4hp (late 1980's/early 1990's), I finally got around to running it on my Zodiac.
Prior to running the outboard, I flushed the tank and changed the gear oil, since I had no idea of the current oil's history. The oil that came out looked good.
Also, I figured that I'd run the mix at 50:1 instead of 100:1, since the engine had been in storage for so long.
After about 5 minutes of full throttle under considerable load (two of us in a little Zodiac - not a prime example of hydro-dynamics) a squeal came from what sounded like the upper portion of the o.b. The squeal came on, then went away, then came on again. It wasn't a tinny squeal (like something a small electric motor would make), more of a squeal/grinding sound. Not a good sound at all.
I shut off the engine. After it had cooled, I double checked the lower end oil. It looked fine, and the level was good.
I put it back on the boat and it started fine and after warming, no squeal.
I'm guessing that it had overheated, and was starting to seize?
Admittedly, I've done nothing about the impeller. There's a moderate amount of water coming out of the little discharge tube, but it's not a steady stream - more of a spittle at idle.
At speed, even though the discharge increases, it's never a steady stream.
Is this normal, or should there be a steady stream, indicating a tired impeller?
When these little ob's overheat do they squeal prior to seizing?
Anything else that I should check?
Prior to running the outboard, I flushed the tank and changed the gear oil, since I had no idea of the current oil's history. The oil that came out looked good.
Also, I figured that I'd run the mix at 50:1 instead of 100:1, since the engine had been in storage for so long.
After about 5 minutes of full throttle under considerable load (two of us in a little Zodiac - not a prime example of hydro-dynamics) a squeal came from what sounded like the upper portion of the o.b. The squeal came on, then went away, then came on again. It wasn't a tinny squeal (like something a small electric motor would make), more of a squeal/grinding sound. Not a good sound at all.
I shut off the engine. After it had cooled, I double checked the lower end oil. It looked fine, and the level was good.
I put it back on the boat and it started fine and after warming, no squeal.
I'm guessing that it had overheated, and was starting to seize?
Admittedly, I've done nothing about the impeller. There's a moderate amount of water coming out of the little discharge tube, but it's not a steady stream - more of a spittle at idle.
At speed, even though the discharge increases, it's never a steady stream.
Is this normal, or should there be a steady stream, indicating a tired impeller?
When these little ob's overheat do they squeal prior to seizing?
Anything else that I should check?
