1972 johnson 20 hp missing and no power

[googlevideo][/googlevideo]
Need help I took my boat out yesterday and it kept missing and at wot it would barely even go and sometimes even die off and I would have to let it run for awhile just to even get it to not die off when is put it in gear. And it will not idle but in neutral you can rev it wide open and as soon as it's put in gear it'll bog down and die off or barely even go.
This is everything thing I've done to try an fix it:
New lines on motor going to pump and carb
New plugs
New points and condensers
New cam magneto
Cleaned and rebuilt the carb
Rebuilt the pump and tested it by squeezing the bulb
New gas tank and connectors
The video is from yesterday when I took it out of it missing and at wot
https://m.youtube.com/watch?v=1-i35LK-PCc

Are you sure the motor is missing, or is it acting like it is popping out of gear?

It may be trying to pop out of gear because it doesn't do that in neutral it just but idk because it just runs terrible in gear like it dies off as soon as I put it in or it Boggs down and has no power at all

you may want to split the gear case and see how the shifter (clutch dog) and gears look.

Thanks man the clutch dog was definitely the problem and there was also water in the oil. How do you think water got in everything looks sealed off to me. And what kind of oil do I use to put back in

That would more than likely be a 90 W Marine Gear Oil.

Y_J's got it right on the oil (80-90W marine)

I use the stuff from walmart: Quicksilver Premium Gear Lube.

As far as where it is leaking it could be any number of seals. Take a look at the parts diagram (https://www.marineengine.com/parts/...=20R72R&manufacturer=Johnson&section=Gearcase) and start with the easiest to replace first. I would do the case seal and the plug seals and put it in a tub of water (no oil) and see if it gets any water inside. If it does not then you could oil it up and run it. Check the case for water. No water - good2go. Water - one of the inner seals is possibly leaking.

That's the same oil I've got here, SomeDumGuy..