Ignition Problems - Automatic choke gets hot?

sn2001

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Aug 14, 2010
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Hey guys

I have been fighting with an ignition problem for over a year on my 1985 sn 2001. My boat starts fine and runs great for the first hour or so but as it gets warmed up it gets harder to start until eventually i just have to let it sit and cool off for ~20 minutes.

I have replaced every component of the ignition except the wires. I also replaced every component of the fuel delivery system (even the fuel lines!!)

Yesterday i was looking at the voltages at all the wires to see if maybe i had a bad wire and i noticed that the wires going to my automatic choke were hot when my ignition was on / as was the automatic choke itself. The engine itself wasn't on. Just the ignition was on. The wires are really the only thing i have yet to replace and it's extremely frustrating trying to track this down :( It's a holley 4160 carb. I read about automatic chokes elsewhere and it sounded like it was supposed to be a temperature gauge only. Hopefully some of the experts can help shine some light on this mystery!
 

Don S

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Re: Ignition Problems - Automatic choke gets hot?

What engine and drive do you have?

The choke is supposed to get hot, that's how it works. As far as things getting hot while the switch is on but the engine is not running, DON"T DO THAT. Assuming (you don't say) that you have a points system, that means the contacts are closed and you are burning up your points. IF electronic, it can burn them up too.
 

sn2001

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Re: Ignition Problems - Automatic choke gets hot?

it's a 1985 ski nautique 2001 with a PCM 351 engine. I converted from points to an electronic conversion kit a mallory e-spark. None of the other wires are hot with the ignition on (but the engine off). Just the wires going to the electronic choke.
 

Don S

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Re: Ignition Problems - Automatic choke gets hot?

My guess is the wire is warm and not HOT. Since the choke coil is nothing more that a big resistor coil that gets hot and expands which is what opens the choke, there is a fair amount of current going through the usually 16ga. wire going to the choke. Resistance causes heat. It could also be that the wire itself is damaged and corrosion has caused it to have a higher resistance.
If you want to get rid of that 12V source of choke power, you can set it up like Volvo and OMC used to do it.
They ran a wire from the AC tap of the alternator to the choke coil. The only time the choke coil had power was when the engine was running.
 

sn2001

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Re: Ignition Problems - Automatic choke gets hot?

OK, good to know thank you!!
 
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