B+S will start but not stay running.

[slomo]

Your engine ignition has probably been converted to the Magnetron ignition, so as points and condenser not required. The magnetron is a good thing.

Parts list shows a magneto.

Oh, it also show points and condenser.

 

[slomo]

check fuel tank it was clean

A tank that old, I doubt was clean. Have to take your word on it. If it came with points she is an old girl.

Removed carb disassembled found old gas residue and some dirt

Found dirt in carb but not in the tank. Ok......

Was the emulsion tube removed and cleaned? Most likely that old carb will need to be boiled for an hour or more. Probably never get the pilot passages to open up who knows.

Check compression 85 lb with 6 pulls, exhaust not obstructed

Was the throttle plate and choke wide open while doing the above test?

Since she has a points system, how wide of a gap does the spark jump? Test the spark until the engine starts to sputter out. Measure where in the gap length it tries to die out. Best to test for spark in low light or a lights out condition.

 

[Rivets]

Slmow, did you read post #8? Have you ever worked on a Flo-jet carb? Flo-jet carbs don’t have an emulsion tube, they do have a main nozzle which provides fuel to both the high speed and idle curcuits. High speed needle controls amount of fuel entering the nozzle for the high speed circuit and the idle needle reduces the fuel needed for the idle circuit. Maybe you should read the service manual I posted.