TomA Show full post »
UPS
TomA;n59719 wrote:
So UPS are you suggesting I replace the solenoid?


No, it can't be bad or it would not have worked when you applied 12 volts to it. There has to be a poor connection somewhere, but which allows enough current to flow for you to measure 12 volts with the solenoid disconnected. The poor connection could be somewhere in the 12 volt feed from the controller (wire 56) to the solenoid - possibly where the choke lead connects to it - or it could be in the solenoid ground wire. If you can't see a problem by closely inspecting the wires, then measuring the voltage at the connected solenoid while cranking is about the only way. You may need to improvise a connection - but be careful.
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TomA
How long should the choke stay closed during cranking? Right now as soon as the engine begins to “catch” the choke comes off but that is obviously too soon. I will try your suggestion but I predict 12V during crank and as soon as the engine begins to fire, 0V. It got a steady 12V before, but that was with the airbox out and the engine had no chance to fire. This is what made me think it’s some sort of control issue. It appears the choke is getting the information to release prematurely.
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Peddler
The choke should stay closed the entire time the unit is cranking or there is 12 volts to the solenoid as the wires are connected. If the choke is opening while it is cranking you have a bad connection somewhere. Now if the engine catches and the starter quits because it gets a run signal from the coil then the choke would open. Without reading back as to what you have done so far I will tell you that I have solved a lot of issues with these 410 engines by replacing the coil which is cheap and easy.
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TomA
Is the engine really going to run perfectly once I manually hold the choke closed if the coil is bad???!!!
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78buckshot
You wont be able to tell by the way it runs, I have replaced coils because of very weak spark or on occasion I could not see any spark but could get the machine started by reducing the spark plug gap. Once it is running the heat of combustion and heat of compression aid in ignition and the unit seems to run with no problem.
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UPS
TomA;n59756 wrote:
How long should the choke stay closed during cranking? Right now as soon as the engine begins to “catch” the choke comes off but that is obviously too soon. I will try your suggestion but I predict 12V during crank and as soon as the engine begins to fire, 0V. It got a steady 12V before, but that was with the airbox out and the engine had no chance to fire. This is what made me think it’s some sort of control issue. It appears the choke is getting the information to release prematurely.


The diagram shows that one of the choke solenoid connections is also designated wire 56, and that it joins wire 56 running from the controller to the starter solenoid midway via a connector. The other connection from both solenoids is a wire 0 going to ground. A poor connection anywhere here can affect either or both solenoids.
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