1995 75LEPTO - Starts and dies consistently

[Boatin_in_KY]

1995 Mercury 75 that hasn't been run in a few years. I changed the impeller, lower gear oil, spark plugs and fuel filter. Hooked the motor up to a fresh tank of gas, and cleaned / filled the oil tank. The motor will start pretty easily, but then will die out pretty quick (all on muffs). I think the longest it ran was about 15 seconds. It will restart immediately. Plenty of water coming out. Lots of white smoke. Fair amount of oil leaking out the prop... does not look like the fresh gear oil I just put in, so I assume it is 2-stroke. Fuel tank vent open. Primer stays hard. At this point I'm fairly certain it's a fuel issue. I plan to check the hoses, and maybe dig into the carbs. If I could get it to run longer, I would do some seafoam... but I am scared that may cause it to not start at all. What are the symptoms of a failing (or bad) fuel pump? Any thing else I should look for?

 

[flyingscott]

How are you starting it give us your procedure. Make sure you are running a 50-1 mix because if you drained the oil tank you could have air in the line.

 

[Boatin_in_KY]

It's auto mix, so I assume it is mixing properly. The choke is on the key as "push" so I am holding while I start, but then letting off. It will die if I hold it of let off. I guess the choke could be stuck or not working? I didn't think about air in the lines, although by now I expect it would be out.

 

[flyingscott]

Run it on pre mix oil does not inject quickly air could be in there for a while which will cause engine damage. Try this for your cold start procedure in the middle of the shifter handle is a button push that in and move the throttle forward until you feel resistance then push in on the key and start it. Carbed motors need to have a little throttle for starting.

By pushing the button in you disconnect the shifting temporarily.