Premix = 50:1 gas/oil mixture, same as in the gas tank.

I don't know merc's too well...some controls have a latch or button that let's you use the regular shift/throttle lever as a warm-up throttle...maybe that unlabelled button is it on yours, or there may be a button on the shift lever that you might not've noticed. [edit--just noticed you already tried that...but surely there's a neutral throttle control somewhere]

Cold start procedure...depends on whether your motor has a true choke, or a primer. When you press the "choke" button you should hear a click -

If your carbs have choke butterflies they should be closed with the button pressed.
If that's the case, just turn the key with the button pressed until it starts. Throttle should be opened if you can figure out how.

If your carbs don't have choke butterflies then you have a primer solenoid that opens a valve and lets fuel drain from the carbs into the engine to richen the mixture for cold starting. Hold the button down for 5 or 8 seconds (key on), then turn the key to start while holding the button.

I believe David's nailed it...you've got trash in your tank - it needs to be drained and flushed and the carbs need to be rebuilt...soak 'em overnight in carb cleaner and blow out all the passages with compressed air and reinstall with new carb kits, make sure you use new gaskets and needle valves & seats. You will definately need a manual to get the link & sync and timing set right after that's done.

Good luck...

BTW cranking for more than 20 seconds or so without a minute or two in between will really shorten the life of your starter.

Man..that really sucks about having to rebuild the carbs if that's the case, cuz I know that was all just done in the overhaul. I just wonder how much trash is really in the tank...

Power Pack is Bad

dont say that crappie!!! lol If that were to be it though... how much am I lookin at to get it fixed?

This is to any mechanics out there... If the power pack, or that high speed wind up, is going out... How long can you operate the boat, and what will eventually happen? Along with costs or possible fixes... Thanks guys!

?

try http://forums.iboats.com/bbBoard.cgi?a=viewforum;fid=29

sounds like **** in the gass tank, have you ever run it dry. if so you sucked in all of the junk left in the tank when they drilled the holes for the hoses. i have a 91' mariner 150 and plastic tanks and unfourntley ran'em dry once. had to pull the breather off and clean all the jets on the carbs, i used a thermostat wire and a bottle of carb cleaner. You just have to keep spraying that carb cleaner in till you get all of the junk out, i also replaced the bulb and hoses.

you have an air leak in one of your fuel lines... ~reason i know... MINE just started doing the same thing!! I was lucky enough to realize this when I pumped the bulb. I was working in the rear compartment and I moved the fuel lines... then when I pumped the bulb I heard a "swooshing" noise... sure enough- get to the lake, run wide open and it starts cutting out!! I backoff and it runs fine again!! Its a very SMALL pinhole somewhere! I will now replace all my rubber fuel lines and bulb and filter.