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Hank F.
Hank F., RV tech - emphasis on gensets
Category: RV
Satisfied Customers: 14889
Experience:  RV tech since the beginning of the millenium.
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4.0 BFA - 1R ONAN GenSet. No fire when starting, but fires

Customer Question

4.0 BFA - 1R ONAN GenSet. No fire when starting, but fires once when start switch is released.
Submitted: 1 year ago.
Category: RV
Expert:  Hank F. replied 1 year ago.
My name is ***** ***** I am going to assist you with this.
What is the rest of the model number, exactly like it is written on the data label?
Customer: replied 1 year ago.
4-0 BFA-1R/16004C (SER843793991)
Customer: replied 1 year ago.
Expert:  Hank F. replied 1 year ago.
Sorry, but I work 2 day jobs, and help on Just Answer in the evenings.
I simply can not be online 24/7.
The first thing I need you to do is to check to see if you are getting 12V to the positive terminal of the coil when the start switch is pressed. Are you?
Next, use a 12V test light, and clamp the ground side to a clean engine ground, and touch the probe to the negative post of the coil. Crank the engine a few times.
Does the light flash?
Customer: replied 1 year ago.
It's my first experience with Just Answers and the response time was so long I started getting antsy. I am not impatient, just needed reassurance that everything is legit.
12v + is confirmed to the + side while starting and just to be sure I ran a jump wire to supply 12v + to it while starting. Got the same result. I use a digital meter, but will go out and get a test light to answer your second question.
Customer: replied 1 year ago.
The test light, connected ground to engine ground, and probe to coil negative remains lit (solid, not flashing) during cranking. Goes off when start switch is released. Still only fires to spark plug once when start switch is released.
Customer: replied 1 year ago.
Since posting the last answer, the symptom has changed. Currently the test light does not light up at all when clamped to engine ground and probed to the coil negative during starting.
Expert:  Hank F. replied 1 year ago.
we are legit. Like I said, I can't be online 24/7, but I am online almost every single day, holidays included. There might be 10 days a year that I do not get online, and those are due to me being somewhere that I can not get a wireless signal.
With what you are seeing, I have to wonder if your points are bad.
Start with checking/cleaning/replacing the points, and make sure they are properly gapped to 0.16".
If your points need to be replaced, I suggest also replacing the condensor.
Let me know how things look.
Customer: replied 1 year ago.
I did clean them today and it didn't help. I will replace them tomorrow if I can find the parts. We'll proceed from there.
Expert:  Hank F. replied 1 year ago.
If you need help getting them, let me know. But you should be able to get them through any Onan dealer.
Customer: replied 1 year ago.
Expert:  Hank F. replied 1 year ago.
No problem.

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