Oil leak

I have a either 1984 or 1986 mercruiser 140 I&O four cylinder. I found an oil leak coming from the starter area which appears to be a vent for the starter, there is also oil on the covering below the engine. My thought is that the rear main bearing is leaking. I am seeking advise on what to do here. I would imagine that the engine has to come out. If so if I replace the bearing does the crankshaft have to come off to replace the bearing? I see I can purchaser a new motor for a little over two thousand dollars. The current engine runs good but the compression check shows about 110 per cylinder. I also just replaced the entire outdrive so I would hate to trash the boat. I also tried rear oil seal stop leak that did not accomplish anything. If anyone has replaced a rear seal and the difficulty involved I would like to hear the difficulty involved. I have found this little four cylinder motor a real nice power plant and nice to operate in this economy.

Re: Oil leak

Galacticia said:

I have a either 1984 or 1986 mercruiser 140 I&O four cylinder. I found an oil leak coming from the starter area which appears to be a vent for the starter, there is also oil on the covering below the engine. My thought is that the rear main bearing is leaking. I am seeking advise on what to do here. I would imagine that the engine has to come out. If so if I replace the bearing does the crankshaft have to come off to replace the bearing? I see I can purchaser a new motor for a little over two thousand dollars. The current engine runs good but the compression check shows about 110 per cylinder. I also just replaced the entire outdrive so I would hate to trash the boat. I also tried rear oil seal stop leak that did not accomplish anything. If anyone has replaced a rear seal and the difficulty involved I would like to hear the difficulty involved. I have found this little four cylinder motor a real nice power plant and nice to operate in this economy.

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Ayuh,... A drop-in replacement would probably fit yer bill,...

I'd be hard pressed to put a motor with 110 psi back in a boat, once it's on the floor...