This is my first post, and I've looked and searched, but haven't found an adequate answer. My apologies if this has been covered, but I couldn't find anything. So, on to my problem:
A week ago, I launched the boat at the lake, and while getting ready to take a spin, I noticed oil on the water. Not a ton, but enough to be concerning. I immediately took the boat back out and noticed gear oil emerging from the front weep hole on the lower unit (1996 Mercruiser Alpha one, Gen 2 with gear oil reservoir in engine bay). I took the lower unit off (leaving the upper attached to the boat), since I knew that I would be needing to replace the water pump for regular maintenance, anyhow. Once I split the lower from the upper, I pulled it down to remove it, and I'd estimate about 1/2 a cup of oil came from the upper drive shaft spline area. This is my first question: is this normal, and perhaps I didn't drain the oil completely? I am assuming that the splines are covered in oil, and it may have taken a while for the oil to drain from the reservoir.
Second question, and probably more important: After I pulled the lower for inspection, I noticed that the shift shaft area (which I thought the leak was likely from the shift shaft seal) was covered with older oil. However, the water pump casing, a little bit of the drive shaft, and inside of the upper unit were also covered with blackened gear oil. This oil appeared to have been there for a while, but it's hard to tell. Even more concerning was that along with this residue, there was also a significant amount of metal grit (sticks to a magnet) mixed in with this oil. I have attached a photo of the lower unit as it currently stands. (You can see where I wiped the impeller housing.)
The fresh oil seen on the pics is the remainder of what drained from the upper when I split the lower from the upper, but the water tube was covered with black soot. I recently fixed some carburetor issues, so there may have been some rich exhaust that caused this.
Regardless, I am usually under the assumption that metal grit is bad, and I didn't think this area should have such a significant amount of oil residue. I haven't done any further work yet. Any thoughts? I'm planning to pressure test the lower to see if oil may be coming from the shift shaft seal, but could this oil have traveled to the places seen on the photo? The ferrous metal is possibly a bigger concern.
Also, no water in the oil, from what I could tell, and I didn't yet find grit in the oil that was drained, but I'll report back if I do.
Thank you!
A week ago, I launched the boat at the lake, and while getting ready to take a spin, I noticed oil on the water. Not a ton, but enough to be concerning. I immediately took the boat back out and noticed gear oil emerging from the front weep hole on the lower unit (1996 Mercruiser Alpha one, Gen 2 with gear oil reservoir in engine bay). I took the lower unit off (leaving the upper attached to the boat), since I knew that I would be needing to replace the water pump for regular maintenance, anyhow. Once I split the lower from the upper, I pulled it down to remove it, and I'd estimate about 1/2 a cup of oil came from the upper drive shaft spline area. This is my first question: is this normal, and perhaps I didn't drain the oil completely? I am assuming that the splines are covered in oil, and it may have taken a while for the oil to drain from the reservoir.
Second question, and probably more important: After I pulled the lower for inspection, I noticed that the shift shaft area (which I thought the leak was likely from the shift shaft seal) was covered with older oil. However, the water pump casing, a little bit of the drive shaft, and inside of the upper unit were also covered with blackened gear oil. This oil appeared to have been there for a while, but it's hard to tell. Even more concerning was that along with this residue, there was also a significant amount of metal grit (sticks to a magnet) mixed in with this oil. I have attached a photo of the lower unit as it currently stands. (You can see where I wiped the impeller housing.)
The fresh oil seen on the pics is the remainder of what drained from the upper when I split the lower from the upper, but the water tube was covered with black soot. I recently fixed some carburetor issues, so there may have been some rich exhaust that caused this.
Regardless, I am usually under the assumption that metal grit is bad, and I didn't think this area should have such a significant amount of oil residue. I haven't done any further work yet. Any thoughts? I'm planning to pressure test the lower to see if oil may be coming from the shift shaft seal, but could this oil have traveled to the places seen on the photo? The ferrous metal is possibly a bigger concern.
Also, no water in the oil, from what I could tell, and I didn't yet find grit in the oil that was drained, but I'll report back if I do.
Thank you!
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