sgtmaj27
Model 5870
ser# 6040062

Recently replaced the controller with an 0h6680D. Since replacing the controller, during start, the starter engages, it sounds like it will start but the starter then disengages and spins for 6-7 seconds and stops. After about 10 seconds the second attempt will start the unit. After that the unit runs fine and produces proper voltage. This happens in auto or manual. Always one failed attempt with starter spinning and then a normal start.

i checked and reset valves to .003. Plug is good and gapped to .028. New battery that checks good. Choke engages and disengages as required. Stepper motor appears to function properly.

Is this a symptom of a bad starter? The current starter was replaced 4 years ago.

Thanks
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Birken Vogt
Not a bad starter. The engine is coughing or kicking over once or twice which will disengage this style starter (Bendix drive) and it will never reengage on its own. Normal behavior.

What is causing the engine not to take of and run is what needs investigation. Things that come to mind are ignition coil bad timing, rubber bellows.

You might also just leave it and see if it gets worse, since it is still working as designed, more or less.
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murphy
Back in 2006 the starter in my 7 kW unit failed one month after installation. The starter would run but the bendix would not engage the flywheel to rotate it. The starter was replaced and it worked fine for the next 11 years. Verify that the mounting bolts for the starter are tight. If it is loose or isn't lined up properly it will have trouble engaging with the flywheel.
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sgtmaj27
Birken Vogt;n59070 wrote:
Not a bad starter. The engine is coughing or kicking over once or twice which will disengage this style starter (Bendix drive) and it will never reengage on its own. Normal behavior.

What is causing the engine not to take of and run is what needs investigation. Things that come to mind are ignition coil bad timing, rubber bellows.

You might also just leave it and see if it gets worse, since it is still working as designed, more or less.


As I was contemplating the problem this afternoon I came up with the same thinking that it is not the starter. I just don't know what else to check. The rubber bellows is fine. I have worm gear clamps on both ends. I replaced the coil several months ago. I had a few times where it would start and run rough then smooth out, especially on real hot days. Thought the choke was sticking, but it seemed to move freely.
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sgtmaj27
murphy;n59071 wrote:
Verify that the mounting bolts for the starter are tight. If it is loose or isn't lined up properly it will have trouble engaging with the flywheel.


There is no binding. The starter engages fine and the engine cranks normally, just when it seems it will start,the starters disengages but continues to spin. The starter then stops and a few seconds later it restarts like it was new. It happens every time. Just have to find out what else is causing the problem. I am now leaning toward a fuel problem.

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Peddler
What type fuel and what pressure?
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sgtmaj27
Peddler;n59074 wrote:
What type fuel and what pressure?


Sorry, NG 7” static, variable around 6” while running.
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78buckshot
For a quick test of the starting circuit, starter, and solenoid, turn the gas off and make several attempts at starting. If the starter engages and cranks through the whole crank cycle without any trouble then you can start looking at fuel. air, and spark. If the starter won't stay engaged then you need to look more into the battery, cables, solenoid, starter. My money is on a bad solenoid.
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sgtmaj27
78buckshot;n59077 wrote:
For a quick test of the starting circuit, starter, and solenoid, turn the gas off and make several attempts at starting.If the starter engages and cranks through the whole crank cycle without any trouble then you can start looking at fuel. air, and spark. If the starter won't stay engaged then you need to look more into the battery, cables, solenoid, starter. My money is on a bad solenoid.


This will be my first test tomorrow....Thanks

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sgtmaj27
78buckshot;n59077 wrote:
For a quick test of the starting circuit, starter, and solenoid, turn the gas off and make several attempts at starting. If the starter engages and cranks through the whole crank cycle without any trouble then you can start looking at fuel. air, and spark. .


I did this check his morning. Tried four times to start, each time the starter stayed fully engaged. Turned gas back on. Purged it through the test port. This time it started up as it should, no starter kick out.

The only difference I can see is the weather. This past week we had extremely hot and humid weather for this area (SE Wisconsin), with dew points around 70 and a LOT of rain. Today it was 65 and dry, dew point in the 50s

I guess I’ll do what Birken Vogt suggest and just see how it operates the next few weeks.

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Birken Vogt
Yes, now even more definitely sounds like something is allowing it to fire once or twice and then not continue to run up to full speed.

This is the downfall of Bendix drive starters. If the engine pops once or twice it will throw out the gear and the spring will keep it disengaged until the next cycle. If it was a solenoid shift it would probably be no issue. Some of the older 20 kw units used to false start like that and the starter would just keep cranking until they were really running.
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Peddler
Replace the coil.
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sgtmaj27
Peddler;n59089 wrote:
Replace the coil.


The coil was just replaced this past May.....for no start during wet weather.
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Peddler
Replace it again, it could have been old stock
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sgtmaj27
Peddler;n59096 wrote:
Replace it again, it could have been old stock


My next order to Ziller will include another coil I guess.


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Peddler
What thickness did you air gap the coil?
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sgtmaj27
Peddler;n59106 wrote:
What thickness did you air gap the coil?


I used a business card. I let the card sit between the coil and the magnets then tightened it down. I should probably check that again though.
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Peddler
You want about .010 which should put you pretty close I use a time card from the shop.
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sgtmaj27
Peddler;n59119 wrote:
You want about .010 which should put you pretty close I use a time card from the shop.


Thanks, Peddler. Using a feeler gauge one side seemed looser than the other. I took my time and set the air gap to .010. Now the motor starts the first time, no starter kick out, with just a slight stumble until full speed. I felt the solenoid to ensure that the choke plate wasn't sticking and there seems to be more of a delay in releasing the choke with this "D" controller than there was with the original "A" version.
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