Electric Choke Connection and Marine Water Heater to Radiator plumbing

RvRev2

Active member
Mar 9, 2024
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Kansas
Howdy all,

Working on two things right now.
1. I took off the air cleaner/filter from the carburetor today, and as I did the blue wire going to the choke fell off its connector. Trouble is, I didn't see which electrical connector it fell off of, and there appears to be three possibilities. There is a two wire plastic connector with a blue wire and a black wire. There is also a single wire plastic connector with the wire being black. I have attached photos below. How can I tell which one is the correct one to re-attach the carb choke?

2. I've got the heater hose, so I was going to re-connect the marine water heater to the radiator. I traced the plumbing from the marine water heater all the way up to the passenger side, rear of the engine. I just can't see where I plumb the lines into the radiator. Once again, pictures attached. Can anyone send me photos of your setup? Give me some direction?

Thanks in advance!
 

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    which electrical connection 2.webp
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  • Which electrical connection 1.webp
    Which electrical connection 1.webp
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  • From Marine Water Heater to Passenger side engine.webp
    From Marine Water Heater to Passenger side engine.webp
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  • Lines from Marine Water Heater.webp
    Lines from Marine Water Heater.webp
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I was told the electronic choke should not have constant key-on power because that keeps the coil constantly heated and can burn out the coil. To me that doesn't make sense since the original choke would have been hot all the time too. 🤷‍♂️. But the carb does "actuate" into the choke open mode at which point you could theoretically stop sending the choke heat and it will stay open. Has anyone bothered with that?
 
I'll check my water heater connections tomorrow, @RvRev2. I noticed one of the tees today when I was working on something else, but I can't quite describe it. For sure it was on a passenger side water hose, fairly far back, but I don't recall what that hose does. I'll have to figure out where the other tee is also.
 
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I was told the electronic choke should not have constant key-on power because that keeps the coil constantly heated and can burn out the coil. To me that doesn't make sense since the original choke would have been hot all the time too. 🤷‍♂️. But the carb does "actuate" into the choke open mode at which point you could theoretically stop sending the choke heat and it will stay open. Has anyone bothered with that?
A timer on the 12V line to the choke might help extend the coil's lifespan, but I don't think they are a high-failure-rate item. The coil might even have an internal limit switch...I don't know. It would be interesting to compare the coil current at start-up versus engine at operating temperature.

Also, the original choke on our engines used a stove design, taking heat from the exhaust cross-overs in the manifold instead of using the electric coil. Newer engines which had the OEM electric choke Qjet may have been designed with an external control for the choke coil.
 
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I was told the electronic choke should not have constant key-on power because that keeps the coil constantly heated and can burn out the coil. To me that doesn't make sense since the original choke would have been hot all the time too. 🤷‍♂️. But the carb does "actuate" into the choke open mode at which point you could theoretically stop sending the choke heat and it will stay open. Has anyone bothered with that?

To close the choke, with the engine cold, one steps fully on the throttle and then lets off the throttle. The choke will close. The engine will start and run on primaries only as the secondaries are prevented from open.

The electric choke heater will cause the choke to open up as the heater works. It takes time to heat up. Blipping the throttle will allow the choke to open fully once the heater warms up, and there are a couple stages to that process, where the engine can be run at an elevated rpm while the engine warms up. Continuous 12V to the choke keeps the choke open.

If you cut power to the choke heater, the next time you stomp on the fuel the choke will close. You'll also lose the secondaries.

The common way to wire this is to connect the choke heater to the center post on the battery isolator. That only see's 12v when the engine is running and the alternator is making 12V. This way, it won't start heating up with the key on if you were waiting for your aux lift pump to fill the carb, or while cranking the engine to start it. It will only start heating once the engine is actually running.
 
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