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3.5 Tohatsu not staying running?

I had this motor working for awhile but all the sudden it wont stay idle it shuts off!

The compression is near 125 and calibrator has been rebuilt, and new fuel, when you start the engine it has to be closed choke, then u let it run then move to open choke. after a while it will begin to stall then need to close choke again, then after it tries to die you can move it to half open choke.. then once it is working a little you can play with the throttle screw tighten then screw it runs fast as you unscrew it the throttle gets slower then it will run for awhile then it will shut off once you have in gear it will run a little but then it
shuts off, this motor will not idle while in gear. Can anyone give me any ideas on this thanks..
 
What on Earth is a "calibrator"?

Your carb and/or fuel system is still a problem. You are too lean. Have you cleaned or replaced the filter in the tank? What method was used to clean the carb? What oil mix ratio are you running?

Yes, when cold, you will need choke to start. As the motor warms, and fuel atomizes more easily, you can ease off the choke. When fully warm, no choke is needed.
Yes, changing the idle stop screw does exactly that -- changes the idle speed. That's how you adjust the correct idle speed.
 
I meantt carburetor and I'm using TC-w3 outboard oil with octane 89. 1 gallon to 16 once of oil .. where is this filter at that you are speaking of? and I rebuilt the whole carburetor.
 
Apparently the fuel passages internal to the carb are restricted, or the filter is restricting flow. Did you soak all non-rubber carb parts for at least 4 hours at room temperature in carb dip, followed by a thorough blow-out using generic carb spray? If not, start there. By "rebuilt", do you mean that you installed a new needle, seat and float, along with gasketing? That was probably a good idea, but is not a substitute for a proper cleaning.

A pint of TCW-3 is enough for 6 gallons. You will foul the plug if you run that much oil. The correct ratio is 50:1 gas-oil.

The fuel cock (attached to the tank) has an integral filter, which can get clogged. See p3-8 and 3-15 of your Factory service manual for location of the fuel cock. If clogged/damaged, it's best to replace the fuel cock (comes with a new filter).
 
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