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Hi,

Was helping a buddy time his engine so we set it at fast idle and did our stuff. Long story short, when it was time to shut the engine off (after running for about 20? minutes - thermofan had kicked in), it wouldn't. Ignition was off, killswitch was hot, engine still ran. Not dieseling, either - it never missed a beat from when the ignition switch was on and killswitch was cold. Here's the kicker - disconnected battery negative (ground) terminal.....and it still ran.

Checked the generic Westfield wiring diagram and I was thinking: could the alternator somehow have kept supplying juice to the coil? Because pulling one of the coil leads (I never got to see which one) was the only thing that killed it.

Since this is going the be an AutoX car, this condition could have serious track consequences. Anyone ever had anything like this before? If not, anyone out there with a guess?

Thanks in advance,
MR2
 

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The alternator can keep the engine running without the battery.

Sounds like it is time to start diagnosing with a multimeter. Start at the coil where you know it stayed hot and work back. My guess is the ignition switch has a short.
 

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Can I ask where you are located? I'm looking to build a Kent 1600 xflow myself, but here in SoCal I don't know any shops familiar with the engine.
 

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re: Engine running without battery

Have to disconnect battery and do any or all of the above:

1. Disconnect the alternator, completely. that is why some racing kill switches have 2 connectors, battery and alternator.

2. Ground alternator excitation field (stops alternator from making electricity, also).

3. Disconnect ignition low tension side, via relay or otherwise.

Alternator will run the motor without battery, which in turn will spin and run the alternator! Connecting alternator and battery on the same side of single pole kill switch creates a nasty DC feedback through the alternator and reverse polarity on all your electrical components.... In other words, singel pole switches are for guys running batteries with no alternator.

Anton
 
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