'86 evinrude 150 V6

Having been into a few outboard shops and seen all that goes on You neet to get the power head off the bottom part ot the outboard . As i stated earlyer you need room to lay out each part as you disassemble the motor Cleaning the wire brushing the bolts is for a very good reason , The threads will be coated with corrosion and rust for sure , if they are clean then you will get a better torq down , The torq wrench will be your friend by the end of the job . It is so easy to pull the thread out of a hole and like stated you someone else Breaking a bolt and having to drill it out .The torq wrench will sae you all thos sorts of hassles . I have said it a few times already but will say again read the manual and know all about hoe the motor is set up . Port and starboard pistons are not the same also the conrods as well they have a top and bottom understand all these things as you take the motor apart . Even put your own makings on things as they are taken off . Am going to say something silly but you do understand how 2 strokes works ?? Sorry not testing you intellegents but some people simply dont have a good understanding !!
Good luck and take your time and dont be in a hurry .

 

I'd pull that port head off ASAP just in case its only a blown head gasket ( these do not last forever) and has let water in, in which case the longer you delay the worse it gets.

 

There is too much focus on disassembling the engine here.
You should first try to diagnose the problem in a non-invasive manner. I like the "if someone else does it, I can do it too" attitude, but doing surgery on an old patient is a risky business, especially if you are an untrained surgeon.

I am not convinced that the low compression is the reason the engine (sometimes) cannot get the boat to plane. Did you follow the standard guidelines like checking the ignition, throttle linkage, cleaning jets and comparing the color of the plug electrodes?

To scrutinize the suspect cylinder wall you can use a fiber optic endoscope. I bought a cheap Japanese one on Ebay, but you may borrow one from a machine shop or the local hospital.

 

Yeah I understand how a 2 stroke works. No worries I'm in no rush to start overhauling the engine. I'm hoping it's something as simple as carbon buildup around the rings. I look at it more as a brain surgeon doing heart surgery, It might not be his specialty but with some guidance and research he should manage to pull it off. That is a good idea about the fiber optic endoscope, I wouldn't mind having one of those on hand anyway. I haven't checked much of anything yet, and I'm going off what my friend said so I have no personal experience running the boat. It's sat for the last 2 years so I'm sure the carbs and jets could use cleaning. Was considering running some sea foam through (assuming it will run) after I clean and inspect things a bit more. I've been debating on if I should try the seafoam or pull that cover and take a look first. Maybe endoscope first...