50 KW Back fire

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brrost@live.com
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Hello,

I have been working on a 50 KW Generac Model QTO5030AVSN.

I just replaced the 3.0L Ford ranger engine with a refurbished engine from O'rielly.

When I manually start the engine it sounds like its ready to start then back fires.

I suspect that my ignition timing is way off. I have limited tools and experience. Can some one please point me in the right direction to begin adjusting the ignition timing and/or wisdom on other issues I can begin trouble shooting.

Thank you for your time.
Respectfully,
Bradley
Chris
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Oh man, what was the reason for the engine swap??

I would verify first that the plug wires are all in the correct spots on the distributor first. Backfires can be devastating to engines if far enough off. :punched: Do you have a timing light with an advance knob or digital readout?

Also, do you have the serial number?
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brrost@live.com
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The exhaust had completely rusted through and water backed into the engine and eventually seized the engine.

I will double check the plug wires.
I do not have a timing light, do you recommend any ones?

Serial number: 4137868

As always thank you Chris.
Chris
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Something like this Actron CP7529 should be just fine. https://amzn.to/3nznbjp It has a digital readout with RPM and advance so you can see where you're at.

Does the engine have timing marks on the balancer?
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I have ordered the timing light. Thanks. I don't recall there being timing marks on the balancer. I will verify tomorrow. How should I approach this problem?
Chris
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Does this unit have a distributor or a coil pack setup?
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It is a coil pack setup.
Chris
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Then you cannot alter the timing. Something else is going on, or a wire isn't connected correctly, or maybe one of the coil harnesses got crossed with another. The timing light probably won't do much good here :sad:
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I have attached a picture of the electronic distributor cap. I just want to verify that it is electronic. It does lead to a sensor that is pointed at the balancer. IF this is the case, I guess its time to look elsewhere. Do you happen to have a resource on the coil harness. I had re arranged the harness to how it was on the previous engine. I appreciate your help Chris. Thank you.
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Electric Distributor cap.jpg
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Chris
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Yea, that is a distributor-less engine. Timing will be set by the ignition system within the controls, or the external ignition module if so equipped.

When you say you moved the harness around, do you mean the spark plug wires? That single connector is the only thing plugged into the coil pack I believe.
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