Starting problem when warm

"Hello,

I have a 3.0 mercru

"Hello,

I have a 3.0 mercruiser 4 cyl, alpha one gen2.. the boat will start right up cold and idle purrrfect, and will run like a top.. when the motor is warm i have to push throttle wide open to start it.. i ahve changed fuel filter, plugs, wires, and had the carb rebuilt.i heard that mercruiser carbs are famous for this behavior, but is that just rumors or am i missing somthing?"

Choke is not opening when warm

Choke is not opening when warm.

No they are not famous for this.

Who rebiult the carb? Did they check to see that the electric choke worked?

To check this take the flame arrestor off.
Put your hand shift control into throttle only that you use for cold start ups and give the throttle one push forward and then back to neutral.
This will allow the choke to close.

turn key to on position.
check for 12 volts at the purple wire at the connector to the choke. ( purple wire is +12 volts and black wire is ground) check between the purple and black to make sure the black is grounded.

If you have 12 volts across the 2 leads the wait a few minutes and then look at the choke butterly and make sure it opened. The choke is controlled by a spirol bymetal spring that when the voltage is applied it acts like a resistor and heats up and when it heats up it moves causing the choke butterfly to open.

If it does not do this than your electric choke is bad. Replace it if you can.

thanks for the advice...will c

thanks for the advice...will check when i get off work today and reply back with a post....