Lean sneeze? 1970 25hp evinrude

[Eyeballsdeep]

So I've been working on this evinrude and changed the points, condensers, (gapped to .020), wires (there was a crack where the "up" tab was) I also checked the compression gave a shot of premix in the plug holes for lube, and got 105psi top and 107psi bottom. I took the carb apart and it was clean. I levelled the float, and blew it out with compressed air.( not in that order) I will put a carb kit in it, but I wanted to see if it would fire up. I also removed the power head and replaced the base gasket. I put it in the tank and tried firing it up, but it will only start with a squirt of fuel down the carb. It's sometimes sneezes, not a back fire. I did get it running but only with partial throttle, and I had to push the linkage to open the throttle plate while pulling it over to get it going, it ran pretty good but won't idle, just dies and then it's a pig to start again and only sneezes, until I manipulate the throttle plate while pulling it over, which is quite a pain. I also need to replace the impeller (no water out the exhaust) the fuel also siphons back to the tank. Is this normal? I know the tank is lower than it would be on the floor than being on the floor in the boat. The primmer bulb gets firm, but after a minute I need to prime it again. I know the fuel bowl is full, but why no fuel? It should start easy with a shot of fuel. Also how do I tighten the tiller to keep the throttle at desired start position? I think this is part of the problem, as well as a carb kit and impeller. I pulled the thermostat cover to inspect and it's dry as a bone. So there is no water getting up there for sure. This none starting issue, does it sound like a carb seal issue? But I still would like to tighten the throttle so it stays open slightly during start up.