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Can I get a serial number?
Ok couple things. If you are getting any water in the cylinders, as evidenced by dropplets on the spark plugs then the engine will not turn up, poor idle, loss of power. Essentially you are running on only 3 cylinders, at best. The leading cause of this is the inner exhaust baffle plate corroding or the gasket deteriorating and leaking.
Run the engine on a flushing cups. Run only for about 3 or 4 minutes at a fast idle, no higher. Then quickly remove the spark plugs and look for water on the plugs.
In addition your compression is borderline on the bottom cylinder. I would run some of Mercury's Power Tune through the engine, then do another compression test and see if the compression improves.
You can check and monitor the ignition with a timing light. Easy diagnosis. Here the biggest problem is poor grounds. Make sure everything is well grounded.
Try these tests and post back your results, we'll go from there.
That's fine let me know.
FYI the number in the serial should be a 1, no letters.
No you don't have access to the bottom bolts. You need to remove the powerhead. You'll also get to check the adapter plate under the block and replace the gasket, check for corrosion between the water cavity and exhaust.